隧道内碎核法的应用

目的探讨隧道内碎核在手法小切口白内障手术娩核中的应用效果。方法2008年4月～8月对65例（69眼）Ⅲ级以上硬核白内障手法小切口手术中进行隧道内碎核联合人工晶状体植入术。结果术后1d,3d和1个月裸眼视力≥0．5者分别为38．24％、52．53％、78．49％。术中、术后并发症较少。结论隧道内碎核法具有切口小、术后散光少、并发症少及操作简单、无需特殊设备之优点，是白内障硬核的一种可行术式。     

脑深部电刺激术治疗Hallervorden-Spatz病一例及文献复习

目的 观察双侧丘脑底核脑深部电刺激术治疗1例Hallervorden-Spatz病的手术效果.方法 将脑深部刺激电极植入双侧丘脑底核,分别于术前、开机后1个月、开机后3个月,12个月时对其进行BFM及BFMDMS评分,评价治疗效果.结果 术前、开机后1个月、开机后3个月、12个月的BFMDMS评分分别为114、35、28、14分,症状改善率刺激1个月时为69%、3个月为75%、12个月为88%.持续刺激未引起任何不良反应,患者不再服用相关药物.结论 双侧丘脑底核脑深部电刺激术能够有效的改善严重的全身性肌张力障碍Hallervorden-Spatz病症状,是一种可供选择的安全有效的治疗方法.     

Immunocytochemical localization of phosphatase inhibitor-1 in rat brain

The localization of phosphatase inhibitor-1 was investigated in rat brain by use of immunocytochemistry. Studies were performed with an affinity purified IgG raised against purified rabbit skeletal muscle inhibitor-1. In rat brain tissue homogenates, this antibody reacted only with a 29 kDa protein corresponding to inhibitor-1. Immunocytochemical studies with this antibody revealed numerous immunoreactive cell bodies and fibers. The highest concentration of immunoreactive perikarya was observed in the caudate-putamen and nucleus accumbens, and these appeared to be exclusively medium-sized neurons. Other areas containing substantial populations of immunoreactive neurons included the suprachiasmatic nucleus of the hypothalamus, lateral hypothalamus, horizontal limb of the diagonal band of Broca, dentate gyrus of the hippocampal formation, habenula, superior colliculus, claustrum, endopiriform nuclei, and neocortex. The distribution of terminals containing inhibitor-1 coincided with the distribution of terminal fields known to originate from the above regions. Thus, plexuses of immunoreactive axons were seen in the globus pallidus, substantia nigra pars reticulata, paraventricular hypothalamus, dorsal thalamus, CA3 region of the hippocampus, and interpeduncular nucleus. These results demonstrate that phosphatase inhibitor-1, a cyclic AMP-regulated inhibitor of phosphatase-1, is differentially distributed in the rat CNS. Given the widespread role of protein phosphorylation and dephosphorylation in intracellular signal transduction, these results suggest that neurons containing high levels of inhibitor-1 may share common, hitherto unrecognized, properties in terms of neurotransmitter regulation and/or responsiveness.     

The pelvic innervation in the rat: different spinal origin and projections in Sprague-Dawley and Wistar rats

WGA-HRP was applied to the pelvic and pudendal nerves of Sprague-Dawley and Wistar rats to compare the segmental levels of the resulting labeling. L₆ and S₁ were the segme its at which the sacral parasympathetic nucleus and the denser primary afferents occurred in Sprague-Dawley rats. The levels found in Wistar rats were S₁ and S₂, Thus indicating a disparity between both strains of rats in the spinal level of the sacral parasympathetic nucleus and the primary afferents.     

A Comparison of the Effects of Medial Preoptic Electrical Versus Electrochemical Stimulation on Luteinizing Hormone-Releasing Hormone Neuronal Responsiveness to Norepinephrine

Recently, we reported that luteinizing hormone-releasing hormone (LHRH) neurons of estrogen-treated, ovariectomized rats have only limited responsiveness to norepinephrine (NE). These conclusions were based upon observations that NE, when infused intracerebroventricularly, produced only minor increases in plasma luteinizing hormone (LH), whereas, similar infusions following preliminary medial preoptic area (MPOA) electrochemical stimulation (ECS) markedly amplified LH secretion. One difficulty with this approach is that ECS produces an irritative lesion and deposits iron within the tissue, whereas, electrical stimulation (ES) does not have such effects. Accordingly, in the present study, we compared the effects of MPOA–ECS versus –ES on LHRH neuronal responsiveness to NE. While equivalent peak LH concentrations occurred within 15 min after MPOA–ECS or –ES, in the ECS group, LH release was sustained, whereas, it abruptly ceased upon termination of ES (at 15 min). The intracerebroventricular pulse infusion of NE at the time of peak LH secretion (30 min) in MPOA–ECS animals markedly amplified LH release. In these animals, plasma LH remained significantly elevated for 75 min before a decline was observed. In contrast, an infusion of NE at the time of maximal LH release in ES rats (16 min) did not augment LH secretion. The second series of studies examined the effects of MPOA infusions of NE in animals receiving preoptic ES. A single infusion of NE 16 min after ES (i.e. one min after termination of ES) did not amplify LH release, but when two NE pulses were given at 5 and 16 min after beginning preoptic ES, peak plasma LH levels were maintained for an additional 30 min before a decline occurred. Pretreatment of rats with a yS-adrenoreceptor antagonist (propranolol) or a monoamine oxidase inhibitor did not affect peak LH responses obtained after either MPOA–ES alone or combined with two pulses of NE infused into the MPOA at 5 and 16 min. We conclude that following cessation of MPOA–ES, LHRH neurons rapidly lose their responsiveness to NE, whereas, rats which received MPOA–ECS retain such responsiveness possibly due to the stimulative properties of the iron deposited by the ECS. Presumably, for NE to trigger an LH surge requires prior removal of some intrinsic inhibitory control which regulates LHRH neuronal responsiveness to NE.     

Horseradish peroxidase and cobalt chloride as neuromarkers in the hypoglossal nucleus

Summary The hypoglossal nucleus in 129 REJ normal mouse strains was investigated using two neuroanatomical markers, namely the cobalt chloride (CoCl₂) and the horseradish peroxidase (HRP) techniques. CoCl₂ was introduced through the cut end of the hypoglossal nerve. In one set of experiments HRP was injected into the hypoglossal nerve, while in the other it was injected into the tongue musculature. Results show that with these techniques the hypoglossal neurons are conspicuously stained and can be easily located among series of brainstem sections. The mean number±SD of neurons in the hypoglossal nucleus was 1,417±37, 846±28 and 1,272±42 using CoCl₂ and HRP injected into the tongue musculature or the hypoglossal nerve, respectively. The estimated length of the nucleus was 0.92 mm with the CoCl₂ technique.     

Delineation of a brain nucleus: comparisons of cytochemical, hodological, and cytoarchitectural views of the song control nucleus HVc of the adult canary

The present investigation used stable area-specific, neuronal properties instead of Nissl stain to delineate the boundaries of the nucleus hyperstriatalis caudal c (HVc) in the telencephalon of the adult male canary. Immunocytochemical procedures combined with retrograde tracing labeled a large population of perennial long-projecting neurons that contain estrogen receptors in the canary HVc. The HVc area defined by the distribution of these neurons was congruent with the HVc area defined in Nissl-stained sections during the breeding period. The HVc area defined in Nissl-stained preparations showed an extensive seasonal change in size, confirming previous results (Nottebohm: Science, 214:1368-1370, '81). In contrast, the HVc area defined by the distribution of the estrogen receptor containing long-projection neurons showed little or no seasonal change in size. Because these neurons are permanent, the HVc seems to be of rather constant size year round. The internal morphology of the HVc, however, undergoes seasonal alterations, which are reflected in changes in size of the HVc area distinguishable in Nissl-stained sections. The combination of cytoarchitectural criteria of Nissl-stained preparations with area-specific cytochemical and hodological markers to delineate the boundaries of a brain nucleus might give new insights in the partitioning and neuronal plasticity of brain areas.     

Electrophysiological analysis of efferent neurons of cat associative parietal cortex

We have studied in acute experiments the neurons of the associative parietal cortex in the cat, using the microelectrode take-off technique. We identified the efferent neurons sending axons to the sensomotor cortex, the red nucleus, and the pontine nuclei by antidromic stimulation. We investigated the collateral branching of axons of neurons projected simultaneously into two of the formations mentioned, using the impulse collision technique. We studied the characteristics of the spatial distribution of efferent neurons in the parietal cortex.Translated from Fiziologicheskii Zhurnal SSSR imeni I. M. Sechenova, Vol. 72, No. 7, pp. 865–873, July, 1986.     

Coincidence of patchy inputs from the lateral geniculate complex and area 17 to the cat's Clare-Bishop area

Pathways from a variety of structures to the largest of the cat's suprasylvian visual areas, the Clare-Bishop area, were found to patchy. These inputs arose from the lateral geniculate complex, from area 18, from area 19, and, as noted by Montero (Brain Behav. Evol. 18:194-218, '81), from area 17. The Clare-Bishop area was previously delineated on the basis of its uniform pattern of connections with cortex and thalamus (Sherk: J. Comp. Neurol. 247:1-31, '86) and found to incorporate pieces of several retinotopically defined areas (Tusa, Palmer, Rosenquist: Cortical Sensory Organization. Vol 2. Multiple Visual Areas. Clifton, NJ: Humana Press, pp. 1-31, '81). However, since individual patches did not correspond to particular retinotopically defined areas, other explanations of afferent patchiness were sought. An obvious question is whether the patches originating from different sources are systematically related to each other. Two hypotheses were considered. First, different inputs--for example, from the lateral geniculate nucleus (LGN) and from area 17--might terminate in intermingled but mutually exclusive zones in the Clare-Bishop area. Second, multiple patches of input might reflect duplicate representations of the corresponding visual field segment in the Clare-Bishop area. Both hypotheses were tested by injecting the lateral geniculate complex and either area 17 or area 19 with different anterograde tracers. In each case the two injections involved regions of the visual field that coincided to some degree, ranging from near-total overlap to almost complete exclusion. The first hypothesis predicted that the different labels in the Clare-Bishop area would never be found to overlap, while the second hypothesis predicted that when injections were closely matched retinotopically, there would be extensive overlap between patches. The results supported the second hypothesis: the better the retinotopic match between injections, the greater the overlap found between labeled geniculate and cortical input in the Clare-Bishop area. However, the multiplicity of patches seen in some experiments, and the close spacing between some patches, suggested that an additional, nonretinotopic mechanism also contributes to patchiness in the projections to the Clare-Bishop area.     

Fine structural studies of growth-hormone-releasing-factor (GRF)-immunoreactive neurons and their synaptic connections in the guinea pig arcuate nucleus

The fine structure of neurons containing human growth-hormone-releasing factor (hGRF) immunoreactivity located in the arcuate nucleus of the guinea pig was studied by means of the preembedding immunohistochemical technique. The perikaryon of labeled neurons was fusiform or ovoid; the nucleus was regular in shape and contained a prominent nucleolus. The main ultrastructural features of the hGRF-immunoreactive neurons were the presence of numerous labeled secretory granules (100-120 nm in diameter) and the abundance and the enlargement of the organelles involved in the synthesis of the peptides: a well-developed rough endoplasmic reticulum and a conspicuous Golgi apparatus. Synaptic inputs were observed on immunoreactive perikarya but, above all, on the labeled dendrites. The unstained presynaptic nerve endings most often contained only small clear vesicles and formed symmetrical contacts. In rare cases, the presynaptic terminals exhibited both small clear and large dense vesicles and constituted asymmetrical contacts. Immunoreactive nerve endings were also observed in this area: the synaptic boutons contained large, stained vesicles and small, unlabeled, clear vesicles. These axon terminals made synaptic contacts with unstained dendritic processes; the contacts were symmetrical. The results indicate that hGRF-immunoreactive neurons of the guinea pig arcuate nucleus present morphological features of neuroendocrine cells. Moreover, the presence of hGRF-labeled nerve endings in the arcuate nucleus itself suggests that a substance related to hGRF might be a neuromodulator, at least in this area.