Origins and pathways of cerebrovascular nerves storing substance P and calcitonin gene-related peptide in rat

Origins and pathways of cerebrovascular substance P- and calcitonin gene-related peptide-positive nerves in rat were studied by immunohistochemistry combined with denervation experiments and retrograde axonal tracer technique. The two peptides have been found to coexist in one and the same neuron. After sectioning of the nasociliary nerve bilaterally the substance P/calcitonin gene-related peptide fibers in the rostral half of the circle of Willis and its branches were eliminated, whereas the number decreased in the caudal half of the circle of Willis and rostral two thirds of the basilar artery. Substance P/calcitonin gene-related peptide fibers in the internal carotid arteries, the caudal third of the basilar artery and the vertebral arteries were not affected by the nerve section. After application of the retrograde axonal tracer True Blue onto the proximal segment of the middle cerebral artery the dye accumulated in several Substance P/calcitonin gene-related peptide-containing cells in the ophthalmic division of the ipsilateral trigeminal ganglion and in a few cells in the maxillary trigeminal division and in the internal carotid miniganglion. No other cranial ganglia accumulating the dye contained any substance P/calcitonin gene-related peptide-positive cells. It is concluded that the rostral portion and part of the caudal portion of the cerebral vessels are innervated by substance P/calcitonin gene-related peptide-containing fibers from the trigeminal ganglion and the internal carotid miniganglion. The great majority of trigeminal fibers reach the vessels via the nasociliary nerve of the ophthalmic division, which enters the cranial cavity through the ethmoidal foramen, whereas fibers from the miniganglion project directly to the bypassing internal carotid artery. A probable pathway for the fibers from the maxillary division is suggested. The caudal portion receives, in addition, a supply from other sensory ganglia (lower cranial and/or upper cervical dorsal root ganglia).     

Neuropeptide Y in non-sympathetic nerves of the rat: changes during maturation but not after guanethidine sympathectomy

Non-sympathetic neuropeptide Y-containing nerves were demonstrated by their persistence after destruction of sympathetic nerve terminals by acute 6-hydroxydopamine treatment for 48 h. In order to examine whether these neuropeptide Y-containing nerves reinnervate tissues following the loss of sympathetic nerves we administered guanethidine sulphate to one-week-old rat pups for three weeks to produce a complete and long-lasting sympathectomy and we monitored the innervation of the superior cervical ganglion, mesenteric vein, vas deferens and urinary bladder by noradrenaline- and neuropeptide Y-containing nerves two and 16 weeks later (assay and histochemical observations). By two weeks the reduction in neuropeptide Y content of tissues was similar to the reduction after acute sympathectomy with 6-hydroxydopamine treatment, indicating that there was no early reinnervation by non-sympathetic neuropeptide Y-containing nerve fibres at a time when sensory transmitters increase. Furthermore, there was no reinnervation by neuropeptide Y-containing nerve fibres by the time these sympathectomized animals had reached maturity, 16 weeks after cessation of treatment. Neuropeptide Y levels increased in the superior cervical ganglion with normal maturation but decreased in the prostatic end of the vas deferens. A non-sympathetic source of neuropeptide Y demonstrated in the immature rat vas deferens was no longer evident in the mature animal.     

Origin and peptide content of nerve fibers in the nasal mucosa of rats

Injection of the retrograde neuronal tracer True blue into the anterior-lateral part of the nasal mucosa of rats labeled nerve cell bodies in the superior cervical ganglion, the sphenopalatine ganglion, the otic ganglion and the trigeminal ganglion on the ipsilateral side. In the superior cervical ganglion, the sphenopalatine ganglion and the trigeminal ganglion on the contralateral side, very few nerve cell bodies were labeled, indicating that these ganglia provide minor contributions only. The number of labeled cell bodies indicates that the superior cervical ganglion, the sphenopalatine ganglion and the trigeminal ganglion contribute most to the innervation of the nose, while the contribution from the otic ganglion is minor. Cell bodies in the superior cervical ganglion harbored noradrenaline (NA) or NA/neuropeptide Y (NPY); in the sphenopalatine ganglion vasoactive intestinal peptide (VIP) or VIP/NPY; in the otic ganglion VIP, VIP/NPY or VIP/substance P (SP) and in the trigeminal ganglion calcitonin gene-related peptide (CGRP) or CGRP/SP. The results from denervations and tracer experiments suggest that all NA-containing and the majority of NPY-containing fibers in the nasal mucosa are derived from the superior cervical ganglion (sympathetic nerve supply). VIP- and VIP/NPY-containing fibers originate from the sphenopalatine and otic ganglia (parasympathetic nerve supply). Nerve fibers containing CGRP and CGRP/SP emanate from the trigeminal ganglion (sensory nerve supply).     

Use of enhanced silver staining combined with electron microscopical immunolabelling to demonstrate the colocalization of neuropeptide Y and vasoactive intestinal polypeptide in cerebrovascular nerves.

The combination of immunolabelling at the electron microscope level and enhanced silver staining has been used to demonstrate the colocalization of neuropeptide Y and vasoactive intestinal polypeptide in perivascular nerves supplying cerebral arteries of the rat. This has been shown in control tissue, but it is easier to demonstrate after long-term sympathectomy since that leads to an enhancement of neuropeptide Y in vasoactive intestinal polypeptide-containing parasympathetic nerves supplying these vessels. Immunolabelling of the antigens for these peptides was performed sequentially with the biotin streptavidin diaminobenzidine method, and the end product to the first antiserum was gold-silver intensified before the visualization of the second antigen. Using this technique, it was shown that all the neuropeptide Y immunoreactivity present in the rat cerebral vessels after long-term sympathectomy with guanethidine was localized in vasoactive intestinal polypeptide-containing nerves. Furthermore, an immunohistochemical analysis of the parasympathetic pterygopalatine ganglia in guanethidine-treated rats showed an increase in the percentage of neurons displaying neuropeptide Y immunoreactivity. In order to clarify if the pterygopalatine ganglion was the origin of those neuropeptide Y/vasoactive intestinal polypeptide-immunoreactive cerebrovascular nerves, which had increased in number after sympathectomy, a fluorescent neuronal tracer (Fast Blue) was applied to the right middle cerebral artery of rats which had undergone guanethidine treatment for six weeks. Immunohistochemical analysis of the ipsilateral ganglion 72 h after application of the tracer revealed the presence of immunoreactivity to both these peptides in retrogradely labelled neurons. It is concluded that neuropeptide Y and vasoactive intestinal polypeptide are colocalized in perivascular parasympathetic nerves supplying the middle cerebral artery of the rat, which have their origin in the pterygopalatine ganglion. Furthermore, long-term sympathectomy with guanethidine leads to an increase in the expression of neuropeptide Y in these vasoactive intestinal polypeptide-immunoreactive neurons.     

Development of AChE-positive, NA-containing and VIP- and NPY-immunoreactive nerves in the major cerebral arteries of the rat

Summary The development of cerebrovascular nerves containing noradrenalin (NA), acetylcholinesterase (AChE), neuropeptide Y (NPY), and vasoactive intestinal polypeptide (VIP) was studied in rats from before birth to adulthood. All these nerves entered the cranial cavity along the cerebral carotid, internal ethmoidal, and vertebral arteries during the early stages of development, but the subsequent growth and distribution of NA-containing and NPY-immunoreactive (IR) nerves differed greatly from that of AChE-positive and VIP-IR nerves. NA-containing and NPY-IR nerves extended rapidly from the cerebral carotid artery and spread over all the major arteries of the internal carotid system by postnatal day 3, as well as descending the posterior ramus of the cerebral carotid to mingle with nerves from the vertebral artery around the mid-basilar artery by day 5. AChE-positive and VIP-IR nerves from the internal ethomoidal artery covered the whole internal carotid system during the first postnatal week, and projected to the upper basilar artery after the second week, while those from the cerebral carotid artery remained limited to the middle cerebral artery throughout development. By day 21, all major arteries of the internal carotid system had dense plexuses of the four nerve types that were similar to those observed in adult rats. The vertebrobasilar system also had a well-organized network of NA-containing and NPY-IR nerves, but only a poor supply of AChE-positive and VIP-IR nerves. Even on day 30, the latter two nerve types were sometimes absent from the middle to caudal basilar artery, owing to a lack of interdigitation by nerves from the internal ethomoidal and vertebral arteries.     

自发性高血压鼠脑底动脉血管活性肠多肽能神经纤维的起源

应用免疫组织化学 ABC法和神经节切除术 ,观察了 2 0只自发性高血压鼠 (分手术 、 、 组和对照组 )脑底动脉血管活性肠多肽能神经纤维的起源。结果显示 ,对照组脑底血管的大脑前动脉、大脑中动脉、大脑后动脉和基底动脉壁上均可见棕褐争的免疫反应阳性纤维 ,纤维似细曲线状 ,呈网状走行。手术 组作一侧蝶腭神经节切除术 ,双侧脑底动脉主要分支的阳性纤维明显减少 ;手术 组作一侧耳神经节切除术 ,双侧大脑后动脉和基底动脉壁上的阳性纤维密度减少 ;手术 组作一侧颈上神经节切除术 ,基底动脉的阳性纤维减少。结果表明 :自发性高血压鼠一侧脑底动脉主要分支的血管活性肠多肽能神经纤维起源于双侧蝶腭神经节、耳神经节和颈上神经节。提示血管活性肠多肽能神经可能在高血压鼠的脑血管运动和高血压的发生和发展方面起着重要的作用     

Distribution and origin of nerve fibers in the rat temporomandibular joint capsule

 The distribution and origin of nerve fibers containing neuropeptides and NOS projecting to the temporomandibular joint capsule (TMJ) of the rat were studied by retrograde tracing in combination with immunocytochemistry. Numerous nerve fibers were seen in the TMJ as revealed by the neuronal marker protein gene product 9.5. Nerve fibers containing neuropeptide Y (NPY), vasoactive intestinal peptide (VIP), pituitary adenylate cyclase activating peptide (PACAP), substance P (SP), calcitonin gene-related peptide (CGRP), and nitric oxide synthase (NOS) were seen in the synovial membrane, the joint capsule and entering the articular disc. Injection of the retrograde tracer True Blue (TB) into the TMJ resulted in the appearance of numerous labeled nerve cell bodies in the trigeminal and superior cervical ganglia, and moderate numbers in the nodose, the otic, the sphenopalatine, the stellate and the dorsal root ganglia at levels C2–C5. Most of the TB-labeled cell bodies in the superior cervical and stellate ganglia contained NPY. In the trigeminal ganglion, numerous TB labeled cell bodies contained CGRP and a minor population stored SP, a few cell bodies were seen to store NOS or PACAP. In the sphenopalatine and otic ganglia, TB labeled cell bodies contained NOS or VIP. In the nodose ganglion, labeled cell bodies contained CGRP; other labeled cell bodies harbored NOS. In the cervical dorsal root ganglia, the majority of the labeled cell bodies stored CGRP and smaller populations stored SP and PACAP. Thus, the innervation of the TMJ is complex and many different ganglia are involved. Accepted: 13 October 1997     

大鼠脑血管颈内动脉系神经肽Y能神经纤维的来源

应用免疫组织化学技术 ABC法和神经节切除术 ,观察了 3 0只 Sprague-Dawley大鼠 (分正常组和四个手术组 )颈内动脉系脑底血管主要分支神经肽 Y( NPY)能神经纤维的起源。正常组大鼠脑底血管大脑前动脉、大脑中动脉和大脑后动脉均可见棕褐色的 NPY能免疫反应阳性纤维 ,呈细线状 ,攀附于血管壁上。手术 组做左侧颈上神经节切除术 ,术后存活 7～ 10 d,发现左侧大脑前动脉、大脑中动脉和大脑后动脉阳性纤维明显减少 ,右侧同名动脉阳性纤维亦有减少 ,但不如同侧明显 ;手术 组做双侧颈上神经节切除术 ,术后存活 7～ 10 d,双侧大脑前动脉、大脑中动脉和大脑后动脉阳性纤维基本消失 ;手术 组做左侧星状神经节切除术 ;手术 组做双侧星状神经节切除术 ,上述各动脉阳性纤维密度都未减少。将手术 、 组各组阳性纤维密度数据与正常组进行对比 ,经统计学分析 ,有显著差异。结果提示 :大鼠一侧颈内动脉系各主要动脉分支的 NPY能神经纤维都起源于双侧颈上神经节 ,但以同侧为主     

高血压鼠脑底动脉神经肽Y能神经与颈上神经节、星状神经节的关系

目的　探讨高血压鼠脑底动脉神经肽Y能神经与颈上神经节、星状神经节的关系。方法　应用神经节切除术和免疫组织化学ABC法 ,对 16只自发性高血压鼠脑底动脉神经肽Y能神经纤维的分布进行了观察。结果　对照组自发性高血压鼠大脑前动脉、大脑中动脉、大脑后动脉和基底动脉壁上均可见神经肽Y能阳性纤维 ,纤维似曲线状 ,多呈网状走行 ,密度较高。手术Ⅰ组作双侧颈上神经节切除术 ,脑底主要动脉的阳性纤维明显减少 ;手术Ⅱ组作双侧星状神经节切除 ,脑底主要动脉壁上的阳性纤维明显减少 ;手术Ⅲ组作双侧颈上神经节和星状神经节切除术 ,脑底主要动脉的阳性纤维完全消失。结论　自发性高血压鼠脑底主要动脉的神经肽Y能神经纤维起源于双侧颈上神经节和双侧星状神经节 ,神经肽Y能神经可能在高血压发病中起作用     

Target-related patterns of co-existence of neuropeptide Y, vasoactive intestinal peptide, enkephalin and substance P in cranial parasympathetic neurons innervating the facial skin and exocrine glands of guinea-pigs

The patterns of co-existence of neuropeptides in cranial autonomic neurons of guinea-pigs have been examined with quantitative double-labelling immunofluorescence and retrograde axonal tracing using Fast Blue. Within the sphenopalatine, otic, sublingual and submandibular ganglia, and a prominent intracranial ganglion associated with the glossopharyngeal nerve, most neurons contained immunoreactivity of vasoactive intestinal peptide, neuropeptide Y, enkephalin and substance P in combinations that were correlated with their projections. Hair follicles in the facial skin formed a major target of sphenopalatine ganglion cells. The combinations of peptides co-existing in these neurons depended upon the region of the skin where the follicles were located. The parotid gland was innervated by neurons with cell bodies in the otic ganglion or the intracranial ganglion. Most of these neurons contained immunoreactivity to all four peptides. The sublingual gland was innervated by local ganglion cells usually containing immunoreactivity to neuropeptide Y, vasoactive intestinal peptide and substance P. The submandibular gland was innervated by local ganglion cells containing enkephalin immunoreactivity and low levels of immunoreactivity to neuropeptide Y. Presumptive vasodilator neurons, containing immunoreactivity to vasoactive intestinal peptide but no other peptide examined here, comprised less than 10% of cranial autonomic ganglion cells. These results demonstrate that the patterns of co-existence of neuropeptides in cranial autonomic neurons show a high degree of target specificity. The discovery that hair follicles form a major parasympathetic target implies a broader range of actions of cranial autonomic neurons than has been suspected until now.     

不同年龄高血压鼠脑底动脉神经肽Y能神经纤维的分布

目的 :为了阐明不同年龄高血压鼠脑动脉神经肽Y(NPY)能神经的分布 ,探索高血压与脑动脉NPY能神经分布的年龄相关性。方法 :应用免疫组化法和神经交点计数法 ,对 12只不同年龄高血压鼠脑动脉NPY能神经纤维分布进行观察。结果 :在 6周龄高血压鼠大脑前动脉 (ACA)和大脑中动脉 (MCA)壁上均见黑色NPY纤维 ,较细 ,曲线状 ,以纵行分布为主 ;在 15周龄高血压鼠ACA和MCA壁纤维密度较高 ,纤维走行以环行为主 ;在 3 0周龄高血压鼠ACA和MCA壁纤维走行以网状为主 ,纤维密度较 6周龄和15周龄鼠增高 ,三个年龄组纤维密度依次为 :3 0周龄鼠 >15周龄鼠 >6周龄鼠。结论 :高血压鼠脑底动脉NPY能神经纤维密度随年龄增加而增高 ,纤维走行由纵行转变成环行、网状分布。提示高血压鼠呈年龄相关性增加的血压可能与高血压鼠脑血管呈年龄相关性增加的NPY能神经相关。     

Long-term chemical sympathectomy leads to an increase of neuropeptide Y immunoreactivity in cerebrovascular nerves and iris of the developing rat

Short-term (surgical) and long-term (chemical) sympathectomy have revealed the presence of a population of neuropeptide Y-like immunoreactive nerve fibres which do not degenerate in parallel with noradrenaline-containing nerves supplying cerebral vessels and the iris of the rat. Two days after bilateral removal of the superior and middle cervical ganglia of 7-week-old rats, noradrenaline-containing nerves could not be detected along any of the arteries of the rat circle of Willis or of the iris, but 18-32% of neuropeptide Y-like immunoreactive nerves remained. Long-term treatment (6 weeks) with guanethidine commencing in developing 1-week-old rats caused degeneration of the sympathetic neurons in cervical ganglia and disappearance of 5-hydroxydopamine-labelled nerves (that showed dense-cored vesicles at the electron microscope level) from rat cerebral vessels, but did not significantly change the density of neuropeptide Y-like immunoreactive axons on the vessels. Furthermore, whilst in control rats neuropeptide Y-like immunoreactivity was localized largely within 5-hydroxydopamine-labelled cerebrovascular nerves, after long-term sympathectomy with guanethidine, neuropeptide Y-like immunoreactivity was seen only in nerves lacking small dense-cored vesicles. A small number of catecholamine-containing nerves appeared along the internal carotid and anterior cerebral arteries after long-term sympathectomy; these may arise from neurons of central origin. These results suggest that as a consequence of long-term sympathectomy with guanethidine, compensatory changes occur, involving an increase in the expression of neuropeptide Y-like immunoreactivity in non-sympathetic axons in cerebrovascular nerves and iris of the rat. In contrast, the neuropeptide Y-like immunoreactive nerves in the dura mater appear to be entirely sympathetic, since none were present after short-term sympathectomy and none appeared after long-term sympathectomy.     

Nerve pathways between the pterygopalatine ganglion and eye in cats

By dissection of thiocholine-stained orbital preparations, it has been determined that three different nerve pathways link the pterygopalatine ganglion and the eye in cats. 1) Nerves from the proximal half of the ganglion join a plexus of nerves and ganglion cells in the rete mirabile of the maxillary artery. Branches of the internal carotid nerve also supply this plexus. Fine nerves from the plexus travel to the optic nerve and then to the eye, accompanying both the nasociliary nerve that passes through the rete and the ciliary arteries that arise from the rete. 2) One or more nerves from the nerve of the pterygoid canal and from a prominent accessory ganglion near the orbital apex course to the inferior optic nerve surface at the optic foramen; these then run distally along the optic nerve to fuse with ciliary nerves or to accompany ciliary arteries entering the eye. 3) Other nerves from the pterygopalatine ganglion travel medially around the extraocular muscle cone to join the ethmoidal and infratrochlear branches of the nasociliary nerve; some nerves from the ganglion then take a retrograde course to the optic nerve, where they join ciliary nerves or arteries to the eye. All three pathways may transmit sympathetic, parasympathetic and somatic sensory nerve fibers.     

Trigeminal fibre collaterals storing substance P and calcitonin gene-related peptide associate with ganglion cells containing choline acetyltransferase and vasoactive intestinal polypeptide in the sphenopalatine ganglion of the rat. An axon reflex modulating parasympathetic ganglionic activity?

In immunohistochemical studies on rat two types of nerve fibres, both showing substance P and calcitonin gene-related peptide-like immunoreactivity, have been localized in the sphenopalatine ganglion, the principal cells of which contain both vasoactive intestinal polypeptide and choline acetyltransferase. One fine-calibre fibre type forms basket-like arrangements around approximately 3–5% of the principal neurons, whereas another, more coarse type traverses the ganglion without making contacts with the ganglion cells. By transection of nerves connecting with the ganglion, in combination with retrograde tracing experiments, it was concluded that the fine-calibre fibres exclusively come from the trigeminal ganglion, whereas the second type in addition, and mainly, originate in the internal carotid ganglion which is situated along the greater superficial petrosal nerve and the pterygoid nerve at their junction with the internal carotid nerve. The brain vasculature was shown to be one target structure for the innervated principal cells in the sphenopalatine ganglion.

The arrangement provides the functional possibility for a modulatory interaction between the autonomie and sensory systems, thus resembling an axon reflex mechanism in the peripheral nervous system.     

Neuronal pathways to the rat thyroid revealed by retrograde tracing and immunocytochemistry

The distribution and origin of the nerve fibres innervating the rat thyroid were studied by immunocytochemistry, retrograde tracing and denervation experiments. Immunocytochemistry revealed nerve fibres containing noradrenaline, neuropeptide Y, vasoactive intestinal peptide, peptide histidine-isoleucine, galanin, substance P, neurokinin A and calcitonin gene-related peptide around blood vessels and follicles. Many of these transmitter candidates were found to co-exist with each other in different combinations in different subpopulations of neurons. Sympathectomy eliminated all noradrenaline- and noradrenaline/neuropeptide Y-containing fibres in the thyroid. Cervical vagotomy eliminated about 50% of the galanin-, substance P- and calcitonin gene-related peptide-containing fibres. Local denervation (removal of the thyroid ganglion and the thyroid nerve) eliminated all galanin- and substance P-immunoreactive fibres and the majority of noradrenaline-, noradrenaline/neuropeptide Y-, vasoactive intestinal peptide- and calcitonin gene-related peptide-containing fibres in the thyroid gland. Injection of True Blue into the thyroid gland labelled cell bodies in the thyroid ganglion, the laryngeal ganglion, the superior cervical ganglion, the jugular-nodose ganglionic complex, the dorsal root ganglia (C2-C5) and the trigeminal ganglion. Judging from the number of labelled nerve cell bodies, the superior cervical ganglion and the thyroid ganglion contribute most to the thyroid innervation, while the laryngeal ganglion and the trigeminal ganglion contribute least. The True Blue-labelled ganglia were examined for the presence of various populations of nerve cell bodies (only major populations are listed). The thyroid ganglion harboured neuropeptide Y, vasoactive intestinal peptide and galanin/vasoactive intestinal peptide cell bodies (in order of predominance); the laryngeal ganglion galanin/vasoactive intestinal peptide, vasoactive intestinal peptide and calcitonin gene-related peptide cell bodies; the superior cervical ganglion noradrenaline/neuropeptide Y and noradrenaline cell bodies; the jugular ganglion calcitonin gene-related peptide, substance P/calcitonin gene-related peptide and galanin/substance P/calcitonin gene-related peptide cell bodies; the nodose ganglion vasoactive intestinal peptide and vasoactive intestinal peptide/galanin cell bodies; the dorsal root ganglia (C2-C5) and the trigeminal ganglion calcitonin gene-related peptide, substance P/calcitonin gene-related peptide and galanin/substance P/calcitonin gene-related peptide cell bodies.(ABSTRACT TRUNCATED AT 400 WORDS)     

Ultrastructural relationships between choline acetyltransferase- and neuropeptide y-containing neurons in the rat striatum.

The relationships between cholinergic and neuropeptide Y-containing neuronal systems in the rat striatum were examined using a dual immunoperoxidase labelling method. These neurons were identified by their immunoreactivity to choline acetyltransferase and neuropeptide Y, respectively, and were visualized on the same sections using 3,3'-diaminobenzidine and benzidine dihydrochloride as distinct chromogens under two conditions: (i) neuropeptide Y detection by the 3,3'-diaminobenzidine diffuse brown reaction product and choline acetyltransferase detection by the benzidine dihydrochloride blue, granular reaction product; (ii) choline acetyltransferase detection by 3,3'-diaminobenzidine and neuropeptide Y detection by benzidine dihydrochloride. Although both neuropeptide Y- and choline acetyltransferase-immunoreactive cell bodies were simultaneously detected and were easily distinguishable whatever the conditions used, neuropeptide Y- and choline acetyltransferase-immunoreactive dendrites and axons could not be visualized on the same sections, since only the diaminobenzidine-labelled processes were detectable. Light microscopic observations on sections dual labelled with either method confirmed that choline acetyltransferase and neuropeptide Y immunoreactivities were localized in morphologically different populations of striatal neurons scattered throughout the striatum, choline acetyltransferase immunoreactivity being associated with large neurons and neuropeptide Y immunoreactivity with medium-sized neurons. In addition, the choline acetyltransferase-immunoreactive neurons were found to be more numerous than the neuropeptide Y-immunoreactive neurons and to be prevalent in the dorsolateral areas of the striatum, whereas neuropeptide Y-immunoreactive neurons were preferentially found in the ventromedial areas of this structure. Electron microscopic observations on sections processed under either condition revealed that choline acetyltransferase-positive terminals form synaptic contacts of the symmetrical type with neuropeptide Y-positive somata and proximal dendrites and that choline acetyltransferase-positive neurons are contacted by neuropeptide Y-positive terminals. These data show that the striatal neuropeptide Y- and choline acetyltransferase-containing neuronal systems have reciprocal synaptic interactions and provide morphological support for the hypothesis that striatal cholinergic and neuropeptide Y interneuron activities may be functionally linked.     

Distribution of somatostatin- and neuropeptide Y-immunoreactive nerve fibers in the porcine female reproductive system.

The localization and distribution of somatostatin and neuropeptide Y were studied in the porcine female reproductive system with the indirect immunofluorescence technique. Somatostatin-immunoreactive nerve fibers were observed in different parts of the ovary and in the muscular membrane of the uterus as well as in the mesosalphinx. Somatostatin-immunoreactive neurons were detected in the inferior mesenteric ganglion. Neuropeptide Y immunoreactivity was present in a large number of nerve fibers distributed in different regions of the uterus, oviduct and ovary. The present results suggest that the porcine female genital organs receive innervation by somatostatin- and neuropeptide Y-containing nerve fibers, but their exact functional role remains to be established.     

An electron microscopic study on the innervation of the intracranial artery of the rat

Topographical variations in the innervation between different portions of rat intracranial artery have been studied by the aid of electron microscopy. Myelinated fibers are found only around the internal carotid and the proximal portion of the basilar arteries. Unmyelinated fibers are observed within the adventitia of the major intracranial arteries. These fibers diminish gradually in number as getting towards the periphery and completely vanish before the disappearance of the muscular coat of the artery. Most of small branch arteries have no vascular nerve around them, although they show one- or two-layered arrangement of smooth muscle cells in the media. Some central branches of the internal carotid and the middle cerebral arteries are accompanied by unmyelinated fibers even after they penetrate into the brain tissue. The fine structures of the terminal portion of vascular nerve fibers, particularly the neuromuscular relationships, have also been described.     

Patterns of reinnervation of denervated cerebral arteries by sympathetic nerve fibers after unilateral ganglionectomy in rats

Summary In order to clarify the manner in which previously denervated cerebral arteries become reinnervated after unilateral excision of the superior cervical ganglion (SCG), we observed directly the reinnervating sympathetic nerve fibers originating in the contralateral SCG by using anterograde labeling with wheat germ aggulutinin-horseradish peroxidase in rats. The nerve fibers sprouted from the nerve fibers in the contralateral anterior cerebral artery and reinnervated the arterial wall of the anterior cerebral artery of the denervated side as early as one week after ganglionectomy. In addition to this sprouting route, three other reinnervating nerve fiber routes were observed in the circle of Willis of the denervated side two weeks after ganglionectomy: the proximal portion of the internal carotid artery, the route passing between bilateral ethmodial arteries, and the posterior communicating artery. Eight weeks after ganglionectomy, these reinnervating nerve fibers formed a fairly dense plexus in a circular pattern in the circle of Willis. However, the reinnervation could not be observed in the arterial branches derived from the circle of Willis (middle cerebral artery and posterior cerebral artery) even 16 weeks after ganglionectomy. The present results clearly demonstrated the time course, distribution pattern and limitation of the reinnervation from the contralateral SCG following unilateral ganglionectomy. The fact that reinnervation could be observed only in the main cerebral arteries of the circle of Willis, in which the nerve plexus appeared to have a circular pattern, suggests a difference between the qualities of sympathetic innervation controlling the cerebral circulation in these arteries and the other arterial branches related to these differences in reinnervation capacity.     

家兔主要大脑动脉胆碱能神经与蝶腭神经节、耳神经节的关系

应用神经节切除术和胆碱酯酸级化法，对19只新西兰家兔大脑前、中、后动脉的胆碱能神经的形态学变化进行了比较观察，目的在于探明主要的大脑动脉胆碱能神经与蝶腭神经节、耳神经节的关系．根据两组动物实验（①非手术组：不切除神经节，只对大脑前、中、后动脉进行胆碱酯酶染色，作为正常对照之用；②手术组：按五组不同组合方式，分别切除神经书，然后进行胆碱酯酶染色，观察不同方式的切除手术后的胆碱能神经的变化）的结果证明：非手术组的各主要大脑动脉壁上均存在丰富的棕红色胆碱能神经纤维，主干及分支都清晰可见，神经纤维密度呈（+++）．手术组各种方式的切除神经节的结果，表现为出现胆碱酯酶聚积现象和神经纤维的分布密度降低（++、+），未发现神经纤维消失．本研究的结果又提示，家兔一侧的主要大脑动脉胆碱能神经的节后神经元可能与双侧的蝶腭神经节和耳神经节有关。