Neuropeptide Y immunoreactivity is preferentially located in rat lumbar sexually dimorphic nuclei

The distribution of neuropeptide Y-like immunoreactivity (NPY-LI) was examined in the ventral gray lumbar spinal cord of male and female rats. Fibers containing NPY-LI were distributed in a sexually dimorphic manner in three motor nuclei: the male cremaster nucleus (CN), spinal nucleus of the bulbocavernosus (SNB) and the dorsolateral nucleus, pars medialis (mDLN) receive a greater number of fibers with NPY-LI than females. Fibers with NPY-LI had the following ratios: males, mDLN greater than or equal to SNB greater than CN greater than dorsolateral nucleus, pars lateralis (1DLN) greater than remaining lumbar ventral gray horn motoneurons (VGH); females, mDLN greater than or equal to SNB greater than or equal to CN greater than VGH greater than or equal to 1DLN. In addition, a previously undescribed small column of motoneurons, located between mDLN and SNB, is outlined by fibers which contain NPY-LI in both sexes. The role of NPY in lumbar sexually dimorphic nuclei is presently unknown.     

Distribution of neurons expressing calcitonin gene-related peptide mRNAs in the brain stem, spinal cord and dorsal root ganglia of rat and guinea-pig

In situ hybridization histochemistry was used to localize calcitonin gene-related peptide mRNAs in spinal cord, brain stem and dorsal root ganglion neurons of the rat and guinea-pig. A 32P-labeled 23-base-long (23mer) oligodeoxyribonucleotide (oligomer) complementary to calcitonin gene-related peptide mRNA sequences encoding residues 23-30 of calcitonin gene-related peptide was used primarily as a probe (CGRP I probe). A 32mer complementary to mRNA sequences for residues 10-20 of calcitonin gene-related peptide (CGRP II probe) was also used as a positive control for specificity of the 23mer for calcitonin gene-related peptide mRNA. In both the guinea-pig and rat calcitonin gene-related peptide mRNA was localized specifically to neurons of the dorsal root ganglion, to spinal motoneurons and to motoneurons of the hypoglossal, facial and accessory facial motor nuclei. Differences in the distribution of calcitonin gene-related peptide mRNA between the rat and guinea-pig included a higher proportion of rat dorsal root ganglion neurons containing calcitonin gene-related peptide mRNA and the localization of calcitonin gene-related peptide mRNA to motoneurons of the ambiguus motor nucleus, parabrachial and peripeduncular nucleus of the rat but not the guinea-pig. In the guinea-pig, in contrast, calcitonin gene-related peptide mRNA was localized also to motoneurons of the abducens, trigeminal, trochlear and oculomotor nerves. The neuronal groups in the intact rat found here to contain calcitonin gene-related mRNA have also been shown previously to contain calcitonin gene-related peptide immunoreactivity in colchicine-treated rats. Colchicine-treated rats, however, have been found to contain additional groups of calcitonin gene-related peptide immunoreactive neurons which, in the intact rats used in the present study, showed no detectable hybridization with the calcitonin gene-related peptide probe.     

Calcitonin gene-related peptide-positive neurons and fibers in the cat dorsal column nuclei

An antiserum raised against the C-terminal region of rat alpha-calcitonin gene-related peptide has been used to investigate the morphology and topographical distribution of neurons and terminals containing calcitonin gene-related peptide in the cat dorsal column nuclear complex. Calcitonin gene-related peptide-positive fibers and axon terminals were denser in the cuneate nucleus than in the other dorsal column nuclei subdivisions and were observed throughout all rostrocaudal levels. They were densest in the dorsal and ventrolateral portions of the middle cuneate. Immunoreactive neurons were observed only in animals pre-treated with colchicine. In these cases, some calcitonin gene-related peptide-positive neurons were present in the cuneate and in the external cuneate. In double-labeling experiments, visualization of calcitonin gene-related peptide immunoreactivity in dorsal root ganglia neurons was combined with the retrograde transport of colloidal gold-labeled wheat germ agglutinin conjugated to inactive horseradish peroxidase injected in the cuneate nucleus. These experiments show that calcitonin gene-related peptide-positive fibers in the cuneate nucleus originate mostly from C3-C6 medium sized dorsal root ganglia neurons but also from some small and large neurons. These results suggest that calcitonin gene-related peptide-positive fibers may convey sensory information from a wide range of peripheral receptors.     

Ontogeny of the calcitonin gene-related peptide in the nervous system of rat brain stem: an immunohistochemical analysis

The ontogeny of the calcitonin gene-related peptide in the neuron system of the rat brain stem was investigated by means of the indirect immunofluorescence technique. Calcitonin gene-related peptide-like immunoreactivity was first detected in the fibers of the nucleus of spinal tract trigeminal nerve on gestational day 18, and thereafter appeared gradually in various brain stem areas such as in the fibers of the solitary tract, gracile nucleus, cuneate nucleus, inferior colliculus, superior colliculus, medial geniculate nucleus and in the neurons of the hypoglossal nucleus, facial nucleus, superior olive, parabrachial area, superior colliculus and peripeduncular nucleus. In colchicine-untreated animals, the immunoreactive fibers increased in number and reached adult level by postnatal day 14, whereas the number of cells reached a maximum between postnatal days 2 and 6 and then decreased in number and immunoreactivity or disappeared, except in some areas such as the superior olive and peripeduncular nucleus, which showed the same immunoreactivity as for adult animals. With colchicine treatment, calcitonin gene-related peptide-like immunoreactive cells were found in more areas of the brain stem such as the abducens nucleus, parabigeminal nucleus, principal oculomotor nucleus, trochlear nucleus and central gray, along with the nuclei which had shown calcitonin gene-related peptide immunoreactivity in the untreated animals. However, the neurons in the inferior olive showed a different ontogenetical pattern of calcitonin gene-related peptide of immunoreactivity. Immunoreactivity disappeared completely by postnatal day 21 in both colchicine-untreated and -treated animals.     

Serotoninergic, peptidergic and GABAergic innervation of the ventrolateral and dorsolateral motor nuclei in the cat S1/S2 segments: An immunofluorescence study

Indirect single- and double-staining immunofluorescence techniques were used to study the serotoninergic, peptidergic and GABAergic innervation of the ventrolateral (Onuf's nucleus) and dorsolateral (innervating intrinsic foot sole muscles) nuclei, located in the S1/S2 segments of the cat spinal cord. The relative density of 5-hydroxytryptamine-, thyrotropin-releasing hormone-, substance P- and γ-aminobuytric acid-immunoreactive axonal varicosities was similar in both nuclei. The highest relative density was recorded for varicosities immunoreactive to γ-aminobutyric acid, while those immunoreactive to 5-hydroxytryptamine or thyrotropin-releasing hormone yielded the lowest values. The density of enkephalin-immunoreactive varicosities was higher in the ventrolateral than in the dorsolateral nucleus. Calcitonin gene-related peptide-like immunoreactivity could be seen in neurons of the ventrolateral and dorsolateral nuclei. Occasionally, calcitonin gene-related peptide-immunoreactive axonal fibers were also encountered in these nuclei. Virtually all thyrotropin-releasing hormone-immunoreactive varicosities in the ventrolateral and dorsolateral nuclei also contained 5-hydroxytryptamine-like immunoreactivity, while a somewhat smaller number of them were co-localized with substance P. About 5–10% of the 5-hydroxytryptamine-immunoreactive varicosities were devoid of peptide-like immunoreactivity, and the number of 5-hydroxytryptamine-immunoreactive varicosities lacking thyrotropin-releasing hormone-like immunoreactivity was higher in the dorsolateral than in the ventrolateral nucleus. Finally, the free fraction of substance P-immunoreactive varicosities, i.e., those lacking both 5-hydroxytryptamine and thyrotropin-releasing hormone, was about 39% in the ventrolateral and 26% in the dorsolateral nucleus. Spinal cord transection at the lower thoracic level induced a depletion of 5-hydroxytryptamine and thyrotropin-releasing hormone-immunoreactive fibers from the ventrolateral and dorsolateral nuclei, indicating an exclusive supraspinal origin for these fibers. A reduction in substance P-like immunoreactivity following spinal cord transection alone or spinal cord transection combined with unilateral dorsal rhizotomy was also detected in both nuclei, suggesting a dual origin for substance P-immunoreactive fibers, i.e., both supra- and intraspinal. The decrease in number of substance P-immunoreactive fibers was however smaller than expected from the analysis of the fraction of substance P-immunoreactive fibers co-localized with 5-hydroxytryptamine, indicating thus that the experimental lesions may have triggered a sprouting of substance P-immunoreactive axons originating from spinal cord sources. The distribution of γ-aminobutyric acid in the ventrolateral and dorsolateral nuclei was not affected by the different lesion paradigms. It is therefore assumed that these inputs are intrinsic to the spinal cord. Finally, both in the ventrolateral and the dorsolateral nucleus a small but statistically significant increase of axonal fibers immunoreactive to enkephalin was seen in response to the experimental lesions.     

Calcitonin gene-related peptide gene expression in collagen-induced arthritis is differentially regulated in primary afferents and motoneurons: influence of glucocorticoids.

Calcitonin gene-related peptide is involved in peripheral and spinal mechanisms of inflammatory pain. In this paper, we used collagen II-induced arthritis in the rat as a model to investigate the influence of chronic arthritic pain on calcitonin gene-related peptide gene expression in sensory and motor pathways. Additionally, we examined the effect of the glucocorticoid drug budesonide on arthritis-induced changes of calcitonin gene-related peptide expression and constitutive calcitonin gene-related peptide expression. Thirteen days after the immunization with native rat collagen type II rats developed a progressive and chronic polyarthritis which was scored with respect to the degree of swelling and/or redness of the paw and ankle joints. Budesonide significantly attenuated the extent of arthritis. Changes in calcitonin gene-related peptide expression were evaluated by semiquantitative in situ hybridization and immunocytochemistry on day 21 post-immunization. In sensory neurons of dorsal root ganglia of arthritic rats, a significant increase in calcitonin gene-related peptide messenger RNA and protein levels was seen. These increases were completely blocked by budesonide. Also in dorsal root ganglia of non-arthritic rats, budesonide had an effect, with reduced calcitonin gene-related peptide messenger RNA levels below constitutive concentrations. Image analysis of calcitonin gene-related peptide immunoreactivity revealed that changes in calcitonin gene-related peptide expression were due to alterations in calcitonin gene-related peptide expression levels rather than to de novo synthesis or changes in the numbers of calcitonin gene-related peptide expressing neurons. In spinal motoneurons of arthritic rats, marked decreases in calcitonin gene-related peptide messenger RNA and protein levels were measured. These reductions were attenuated by budesonide. The changes in calcitonin gene-related peptide expression in motoneurons correlated with the severity of arthritis in the ipsilateral hind paw. Budesonide had no effects on calcitonin gene-related peptide messenger RNA levels in motoneurons of non-arthritic rats. The opposite regulation of calcitonin gene-related peptide gene expression in primary sensory and spinal somatomotor pathways in collagen-induced arthritis suggests that calcitonin gene-related peptide plays a specific role in both chronic inflammatory pain and arthritis-induced motor dysfunction. The sensitivity of constitutive and inflammation-induced sensory calcitonin gene-related peptide expression to budesonide treatment may indicate that the beneficial effects of steroid treatment in inflammation is partly mediated by down-regulation of calcitonin gene-related peptide in sensory neurons involved in neurogenic inflammation.     

Projections of peptide-containing neurons in rat colon

The distribution, origin and projections of nerve fibers containing vasoactive intestinal peptide, substance P, neuropeptide Y, galanin, gastrin-releasing peptide, calcitonin gene-related peptide, somatostatin or enkephalin were studied in the midcolon of the rat by immunocytochemistry and immunochemistry. Most of these nerve fibers had an intramural origin as was established by extrinsic denervation (serving of mesenterial nerves). Extrinsic denervation eliminated neuropeptide Y-containing fibers of presumably sympathetic origin together with sensory nerve fibers containing both substance P and calcitonin gene-related peptide. Co-existence of two peptides in the same neuron was studied by double immunostaining. This revealed co-existence of neuropeptide Y and vasoactive intestinal peptide in one population of intramural neurons; an additional population of intramural neurons was found to contain vasoactive intestinal peptide but not neuropeptide Y. All somatostatin-containing neurons in the submucous ganglia were found to harbor calcitonin gene-related peptide. A much larger population of submucous neurons containing calcitonin gene-related but not somatostatin was also detected. Some perivascular calcitonin gene-related peptide-containing nerve fibers (of intrinsic origin) harbored vasoactive intestinal peptide while others (of extrinsic origin) harbored substance P. The polarities and projections of the various peptide-containing intramural neurons in the transverse colon were studied by analysing the loss of nerve fibers upon local disruption of enteric nervous pathways (myectomy or intestinal clamping). Myenteric neurons containing vasoactive intestinal peptide, galanin, gastrin-releasing peptide, calcitonin gene-related peptide, somatostatin or vasoactive intestinal peptide/neuropeptide Y gave off 5-10-mm-long descending projections while those containing substance P or enkephalin issued approx. 5-mm-long ascending projections. Submucous neurons containing calcitonin gene-related peptide, somatostatin/calcitonin gene-related peptide or gastrin-releasing peptide issued both ascending (2-6 mm) and descending (2-6 mm) projections, those containing vasoactive intestinal peptide issued ascending (approx. 2 mm) projections, while those containing galanin or vasoactive intestinal peptide/neuropeptide Y lacked demonstrable oro-anal projections. Enkephalin-containing fibers could not be detected in the mucosa and the mucosal substance P-containing nerve fibers were too few to enable us to delineate their projections.     

Mapping of CGRP in the alpaca (Lama pacos) brainstem

In this study, we demonstrate the presence of immunoreactive structures containing calcitonin gene-related peptide in the alpaca brainstem. This is the first time that a detailed mapping of the cell bodies and fibers containing this neuropeptide in the alpaca brainstem has been carried out using an immunocytochemical technique. Immunoreactive cell bodies and fibers were widely distributed throughout the alpaca brainstem. A high density of calcitonin gene-related peptide-immunoreactive perikarya was found in the superior colliculus, the dorsal nucleus of the raphe, the trochlear nucleus, the lateral division of the marginal nucleus of the brachium conjunctivum, the motor trigeminal nucleus, the facial nucleus, the pons reticular formation, the retrofacial nucleus, the rostral hypoglossal nucleus, and in the motor dorsal nucleus of the vagus, whereas a high density of fibers containing calcitonin gene-related peptide was observed in the lateral division of the marginal nucleus of the brachium conjunctivum, the parvocellular division of the alaminar spinal trigeminal nucleus, the external cuneate nucleus, the nucleus of the solitary tract, the laminar spinal trigeminal nucleus, and in the area postrema. This widespread distribution indicates that the neuropeptide studied might be involved in multiple functions in the alpaca brainstem.     

Striatal calcitonin gene-related peptide-like immunoreactive afferents from the regions ventral and medial to the medial geniculate nucleus of rats

The sources of fibers with immunoreactivity to calcitonin gene-related peptide in the caudal portion of the caudate-putamen were investigated in animals treated by a knife cut, a tracer injection, or an electrolytic lesion of regions ventral and medial to the medial geniculate nucleus. Hemitransection of the brain just caudal to the caudate-putamen decreased ipsilaterally calcitonin gene-related peptide-like immunoreactivity in the caudal portion of the caudate-putamen, suggesting that calcitonin gene-related peptide-like immunoreactive fibers in the caudate-putamen originated from neurons in the area caudal to the caudate-putamen. Some calcitonin gene-related peptide-like immunoreactive neurons in the regions ventral and medial to the medial geniculate nucleus, including the peripeduncular, posterior intralaminar and suprageniculate nuclei, were labeled ipsilaterally with a retrograde tracer after an injection into the caudal portion of the caudate-putamen. In addition, an electrolytic lesion of calcitonin gene-related peptide-like immunoreactive neurons in the regions ventral and medial to the medial geniculate nucleus decreased the number of calcitonin gene-related peptide-like immunoreactive fibers in the ipsilateral caudal portion of the caudate-putamen. These results suggest that some cells containing calcitonin gene-related peptide in several posterior thalamic nuclei project to the caudal caudate-putamen.     

Calcitonin gene-related peptide in rat spinal cord motoneurons: subcellular distribution and changes induced by axotomy.

Using light and electron microscopy, a study has been made of the changes of calcitonin gene-related peptide-like immunoreactivity in rat lumbar spinal cord motoneurons during cell body response to sciatic nerve injury. At light microscopy level, calcitonin gene-related peptide-like immunoreactivity was evaluated using an indirect immunofluorescence technique combined with Fast Blue retrograde tracing and a peroxidase-antiperoxidase procedure. The calcitonin gene-related peptide changes to sciatic nerve transection and crushing were compared. Calcitonin gene-related peptide-like immunoreactivity was transiently increased after the peripheral nerve lesion, but the response was sustained for a longer period when the peripheral nerve was transected and nerve regeneration prevented. The first changes in calcitonin gene-related peptide-like immunoreactivity were detected four days after nerve crush or transection. In animal spinal cords to which nerve crush had been applied, the maximal enhancement of immunoreactivity was found 11 days after lesion. This was followed by a gradual decline, normal levels being attained 45 days after nerve crushing. When the nerve was transected, the response was similar, but the maximal calcitonin gene-related peptide-like immunoreactivity was maintained over a period of between 11 and 30 days. As with crushing, an important decrease was observed after 45 days. The ultrastructural compartmentation of calcitonin gene-related peptide-like immunoreactivity was studied using either peroxidase-antiperoxidase method or immunogold labelling. Calcitonin gene-related peptide-like immuno-reactivity was located in restricted sacs of the Golgi complex, multivesicular bodies, small vesicles and tubulo-vesicular structures. Large, strongly labelled vesicles resembling secretory granules were also observed in neuronal bodies. Our results reveal that the increase of calcitonin gene-related peptide in motoneurons is a relevant change the cell body undergoes in response to peripheral injury. The ultrastructural location of the peptide distribution suggests specific compartmentation on tubulo-vesicular structures connected with the Golgi complex which form a network in the neuronal cytoplasm. The distribution pattern observed may be related to the sorting and delivery of calcitonin gene-related peptide to secretory vesicles.     

Projections of peptide-containing neurons in rat small intestine

The distribution, origin and projections of nerve fibers containing vasoactive intestinal peptide, neuropeptide Y, somatostatin, substance P, enkephalin and calcitonin gene-related peptide were studied in the rat jejunum by immunocytochemistry and immunochemistry. Their origin was determined by the use of various procedures for extrinsic denervation (chemical sympathectomy, bilateral vagotomy or clamping of mesenterial nerves). The terminations of the different types of intramural nerve fibers were identified by examination of the loss of nerve fibers that followed local disruption of enteric nervous pathways (intestinal myectomy, transection or clamping). The majority of the peptide-containing nerve fibers in the gut wall were intramural in origin, each nerve fiber population having its own characteristic distribution and projection pattern. Nerve fibers emanating from the myenteric ganglia terminated within the myenteric ganglia and in the smooth muscle layers: those storing vasoactive intestinal peptide/neuropeptide Y, somatostatin and substance P were descending, those storing enkephalin were ascending and those containing calcitonin gene-related peptide projected in both directions. Nerve fibers emanating from the submucous ganglia terminated mainly within the submucous ganglia and in the mucosa: those storing calcitonin gene-related peptide or vasoactive intestinal peptide/neuropeptide Y were ascending and those storing substance P or somatostatin were both ascending and descending. Enkephalin nerve fibers could not be detected in the mucosa.     

Existence and coexistence of calcitonin gene-related peptide, vasoactive intestinal polypeptide- and somatostatin-like immunoreactivities in spinal cord motoneurons of developing embryos and post-hatch chicks

By use of immunocytochemical methods, it is shown that immunoreactive calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP) and somatostatin (SOM) are present in motoneurons in the chicken spinal cord. While CGRP-like immunoreactivity (LI) is present in numerous motoneurons both before and after hatching, SOM- and VIP-LI markedly decline at the end of the embryonic period. Evidence is also provided for coexistence of some of these peptides in certain spinal motoneurons.     

The superior olivary complex of the hamster has multiple periods of cholinergic neuron development

Cholinergic neurons of the superior olivary complex share a common embryological and phylogenetic origin with brainstem motor neurons and serve as the major descending efferent pathway either to the cochlea as part of the olivocochlear system or to the cochlear nucleus. In this study, we investigated the developmental expression patterns of choline acetyltransferase (ChAT) and its co-localization with calcitonin gene-related peptide within the superior olivary complex and neighboring brainstem motor nuclei. At embryonic day 12, neurons in the ventral nucleus of the trapezoid body were first to express ChAT. The temporal expression pattern of both ChAT mRNA and immunoreactivity in this periolivary region mimicked motor neurons in the facial and trigeminal motor nuclei. Just before birth, shell neurons surrounding the lateral superior olive expressed ChAT. Neither ChAT-positive periolivary neurons nor shell neurons co-expressed calcitonin gene-related peptide during development or in the adult. Immediately following birth, intrinsic neurons within the lateral superior olive expressed ChAT but not calcitonin gene-related peptide. However, a transient increase in the number of ChAT-positive neurons in the lateral superior olive coincided with the onset of the calcitonin gene-related peptide co-expression within these neurons. We conclude that ChAT expression appears first in periolivary regions containing medial olivocochlear neurons, precedes the expression of calcitonin gene-related peptide in the superior olivary complex, and is co-expressed with calcitonin gene-related peptide within the lateral superior olive containing lateral olivocochlear neurons. These data suggest that the lateral olivocochlear system co-expresses ChAT and calcitonin gene-related peptide, whereas the medial olivocochlear system does not.     

Calcitonin gene-related peptidergic projection from the parabrachial area to the forebrain and diencephalon in the rat: an immunohistochemical analysis

We investigated ascending fiber projections of calcitonin gene-related peptide from the parabrachial area to the forebrain and diencephalon in the rat using immunocytochemistry. Destruction of the lateral portion of the dorsal parabrachial area resulted in a marked ipsilateral decrease in the fibers containing calcitonin gene-related peptide in the ventromedial hypothalamic nucleus, indicating that cells containing calcitonin gene-related peptide in the lateral portion of the dorsal parabrachial area projected to the ipsilateral ventromedial hypothalamic nucleus. Destruction of the ventral portion of the parabrachial area resulted in a marked decrease of fibers containing calcitonin gene-related peptide in the bed nucleus of the stria terminalis, the central amygdaloid nucleus and the lateral hypothalamus just medial to the crus cerebri (the far-lateral hypothalamus), and a less marked decrease in the ventromedial thalamic nucleus. This means that there are projections from cells containing calcitonin gene-related peptide in the ventral portion of the parabrachial area to the first three regions just mentioned, and to some extent to the last.     

Calcitonin gene-related peptide-like immunoreactivity marks putative visceral sensory pathways in human brain

Calcitonin gene-related peptide serves as a neuromodulator in several ascending visceral sensory pathways from the parabrachial nucleus to the thalamus, amygdala and the visceral sensory cortex in rats, but these pathways have not been studied in primates. We have examined the distribution of calcitonin gene-related peptide-like immunoreactive innervation of the corresponding areas of the human brain, including the cortex, diencephalon and brainstem. We report the finding of three populations of calcitonin gene-related peptide-like immunoreactive cells that are homologous to those that have been characterized in the rat: the external lateral and external medial parabrachial subnuclei and the posterior intralaminar thalamic complex, including the subparafascicular, lateral subparafascicular and peripeduncular nuclei. In addition, scattered calcitonin gene-related peptide-like immunoreactive cells were found in the periventricular hypothalamus. Calcitonin gene-related peptide-like immunoreactive terminals were found in regions homologous to the projection areas of the external medial and external lateral parabrachial subnuclei in the rat, including the ventroposterior parvicellular nucleus of the thalamus, the central nucleus of the amygdala, the bed nucleus of the stria terminalis and the insular cortex; and in the terminal field of the posterior intralaminar thalamic complex, including the amygdalo-striatal transition region and the insular cortex.These results suggest that, similarly to other species, calcitonin gene-related peptide may also serve as a marker for ascending visceral sensory pathways in the human brain.     

In situ hybridization studies on mRNAs for cholecystokinin, calcitonin gene-related peptide and choline acetyltransferase in the lower brain stem, spinal cord and dorsal root ganglia of rat and guinea pig with special reference to motoneurons

In situ hybridization techniques were used to analyse the distribution of cholecystokinin (CCK) mRNA in the lower brain stem, spinal cord and dorsal root ganglia of the rat and guinea pig, in comparison with that of mRNAs for calcitonin gene-related peptide (CGRP) and choline acetyltransferase. In the rat, CCK mRNA was found in numerous motoneurons in the spinal cord as well as in the motor trigeminal, facial and hypoglossal nuclei. Coexistence of CCK mRNA and CGRP mRNA could be established in spinal and brain stem motoneurons. Conversely, in the guinea pig CCK mRNA could only be detected in few motoneurons in the spinal cord. In both species, CCK mRNA was present in the spinal trigeminal nucleus and in the dorsal horn of the spinal cord, in numerous small cells located in the outer laminae (mainly II-IV), and in the rat was also found in large cells in laminae IV and V. Few small cells in laminae VI-VIII and X of the spinal cord and cells in several brain stem nuclei, such as the solitary tract, gracile and cuneate nuclei, also showed CCK mRNA in the rat. In the guinea pig brain stem CCK mRNA was found, among others, in the solitary tract nucleus, pontine reticular formation and pontine periventricular grey. In dorsal root ganglia CCK mRNA was abundant in the guinea pig, but almost absent in the rat, where only single cells were found that expressed low levels of this mRNA.     

Immunohistochemical study on the distribution of neuropeptides within the pontine tegmentum--particularly the parabrachial nuclei and the locus coeruleus of the human brain.

The topographical distribution of neuropeptide-containing cell bodies, fibers and terminals was studied in human parabrachial nuclei and the pontine tegmentum with immunohistochemical stainings. Brains of seven adult human subjects of 35-72 years were fixed within 2 h post mortem. Serial sections were immunostained by antisera of 14 different neuropeptides--oxytocin, vasopressin, thyrotropin-releasing hormone, angiotensin II, calcitonin gene-related peptide, beta-endorphin, dynorphin A, dynorphin B, leucine-enkephalin, alpha-melanocyte stimulating hormone, substance P, neuropeptide Y, cholecystokinin and galanin--alternately. All of these peptides were found to be present in nerve fibers and terminals, but only two, angiotensin II and dynorphin B, in cell bodies of the parabrachial nuclei. Calcitonin gene-related peptide-, neuropeptide Y-, cholecystokinin- and galanin-immunoreactive cells were present in other areas of the pontine tegmentum, like the motor trigeminal nucleus, locus coeruleus, periventricular gray matter but not in the parabrachial nuclei. Peptidergic fibers were distributed unevenly throughout the pontine tegmentum having unique, individual distribution patterns. In the parabrachial nuclei, substance P, neuropeptide Y, cholecystokinin and galanin showed the highest density of immunoreactive neuronal networks. Moderate to low concentrations of immunoreactive processes were detected by calcitonin gene-related peptide, alpha-melanocyte stimulating hormone, dynorphin B, thyrotropin releasing hormone, leucine-enkephalin, dynorphin A, angiotensin II, beta-endorphin, vasopressin and oxytocin antisera, respectively. Other pontine tegmental areas, like the locus coeruleus, dorsal tegmental, pontine raphe and motor trigeminal nuclei as well as the central gray of the tegmental region exhibited a varying assortment of neuropeptides with distinct, individual localization patterns. Their detailed topographical distributions are mapped and given in coronal sections.     

Central distribution of efferent and afferent components of the pudendal nerve in rat

Summary Central distribution of efferent and afferent components of the pudendal nerve was examined in the rat by the horseradish peroxidase (HRP) method after HRP application to the central cut end of the pudendal nerve. The pudendal motoneurons were located in the dorsolateral, dorsomedial and lateral groups at L5 and L6. Each of the dorsolateral and dorsomedial groups constituted a slender longitudinal cell column. Pudendal motoneurons in the lateral group were scattered at L5, rostrodorsally to the dorsolateral group. The neurons in the dorsolateral and lateral groups were labelled with HRP applied to the nerve branch innervating the ischiocavernosus and sphincter urethrae muscles. The neurons in the dorsomedial group were labelled with HRP applied to the branch supplying the sphincter ani externus and bulbospongiosus muscles. Some dendrites of pudendal motoneurons in the dorsomedial group extended to the contralateral dorsomedial group. These crossing dendrites were observed not only in male rats but also in female. The average number of the pudendal motoneurons in the dorsolateral and dorsomedial groups were larger in male rats than in female. A few neurons of the intermediolateral nucleus at upper L6 were also labelled with HRP applied to the dorsalis penis (clitoridis) nerve. Axon terminals of the pudendal nerve were distributed, bilaterally with an ipsilateral predominance, to the gracile nucleus, as well as to the dorsal horn and dorsal commissural gray from L4 to S2. A few labelled axons were seen in the intermediolateral nucleus at L6 and S1. Axon terminals from the dorsalis penis nerve were distributed more medially in the dorsal horn than those from the perinealis nerve.     

The suprachiasmatic nucleus of the golden hamster: immunohistochemical analysis of cell and fiber distribution

The distribution of vasopressin-, vasoactive intestinal polypeptide-, somatostatin-, avian pancreatic polypeptide-, 5-hydroxytryptamine- and glutamic acid decarboxylase-like immunoreactivity was analyzed in the suprachiasmatic nuclei of male and female golden hamsters. Vasopressin. Vasopressin-like immunoreactivity is localized within neurons, dendrites and axons throughout the rostrocaudal extent of the suprachiasmatic nuclei. Immunoreactive perikarya are restricted to the dorsomedial aspect of each nucleus and occur in highest numbers within the intermediate two-thirds of the rostrocaudal axis. Axons containing vasopressin-like immunoreactivity form a dense plexus in the dorsomedial suprachiasmatic nuclei and in a vertical column at the lateral aspect of each nucleus. Somatostatin. Somatostatin-like immunoreactivity is also contained in neurons in the dorsomedial aspect of the suprachiasmatic nuclei and in thin varicose axons distributed throughout the suprachiasmatic nuclei in a pattern similar to that of vasopressin-immunoreactive axons. Vasoactive intestinal polypeptide. Vasoactive intestinal polypeptide-immunoreactive neurons are concentrated in the ventrolateral portion of each nucleus and occur almost exclusively within the intermediate two-thirds of the rostrocaudal axis. An extremely dense plexus of varicose axons exhibiting vasoactive intestinal polypeptide-like immunoreactivity extends throughout the suprachiasmatic nuclei and passes out of the dorsal aspect of each nucleus into the periventricular and anterior hypothalamic areas. Avian pancreatic polypeptide. Avian pancreatic polypeptide-like immunoreactivity is restricted to axons which arborize within the ventrolateral aspect of each nucleus. These fibers extend throughout the rostrocaudal extent of each nucleus and partially overlap the terminal field of retinal afferents. Glutamic acid decarboxylase. A very dense plexus of axonal varicosities exhibiting glutamic acid decarboxylase-like immunoreactivity fills both the dorsomedial and ventrolateral portions of the suprachiasmatic nuclei throughout the rostrocaudal extent of each nucleus. Lightly stained immunoreactive perikarya also occur throughout the suprachiasmatic nuclei. 5-Hydroxytryptamine. 5-Hydroxytryptamine-like immunoreactivity is restricted to axons which form a plexus in the ventromedial portion of each nucleus that is most dense in the intermediate two-thirds of the rostrocaudal axis.(ABSTRACT TRUNCATED AT 400 WORDS)