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51.
目的探讨EGF(epidermal growth factor)在成年猴脊髓的表达。方法EGF特异性抗体的免疫细胞化学染色技术(SP法)。结果EGF免疫阳性物质主要位于神经元胞浆内,前角前内侧核、前角前核和前角前外侧核的大运动神经元以及背核的大神经元具有强免疫阳性信号,中等强度免疫阳性神经元主要分布于前角后内侧核、前角中央核、前角后外侧核和前角后外侧后核、中间内侧核和中央管周围,弱阳性神经元主要位于后角边缘核、胶状质、后角固有核和后角连合核。此外,在脊髓白质中可见部分EGF阳性胶质细胞和纤维。结论EGF免疫阳性反应产物在猴脊髓有广泛的分布,提示其功能可能涉及多种神经元和非神经细胞,为探讨表皮生长因子在猴脊髓分布规律和功能提供了有价值的形态学资料。 相似文献
52.
The perirhinal cortex is known to support high-level perceptual abilities as well as familiarity judgments that may affect recognition memory. We tested whether poor perceptual abilities or a loss of familiarity judgment contributed to the recognition memory impairments reported earlier in monkeys with PRh lesions received in infancy (Neo-PRh) (Weiss and Bachevalier, 2016; Zeamer et al., 2015). Perceptual abilities were assessed using a version of the Visual Paired Comparison task with black&white (B&W) stimuli, and familiarity judgments were assessed using the Constant Negative task requiring repeated familiarization exposures. Adult monkeys with Neo-PRh lesions were able to recognize B&W stimuli after short delays, suggesting that their perceptual abilities were within the range of control animals. However, the same Neo-PRh monkeys were slower to acquire the Constant Negative task, requiring more exposures to objects before judging them as familiar compared to control animals. Taken together, the data help to account for the differential patterns of functional compensation on previously reported recognition tasks following neonatal versus adult-onset PRh lesions, and provide further support to the view that the PRh is involved in familiarity processes. 相似文献
53.
RATIONALE: Gonadal steroid hormones altered opioid antinociception under some conditions in rodents, and we reported previously that chronic estradiol enhanced kappa but not mu opioid antinociception in ovariectomized rhesus monkeys. Sex differences have also been observed in the antinociceptive effects of opioid agonists. These findings suggest that gonadal hormones may modulate opioid antinociception. OBJECTIVES: To extend our previous studies of estradiol by examining the effects of progesterone alone, estradiol in combination with progesterone, and testosterone alone on opioid antinociception in ovariectomized rhesus monkeys. METHODS: Opioid effects were studied during chronic treatment with vehicle (sesame oil) or with progesterone alone (P; 0.32 mg/kg per day), a combination of progesterone+estradiol (P+E; 0.32 mg/kg per day P + 0.002 mg/kg per day E), or testosterone alone (T; 0.32 mg/kg per day). Opioid antinociception in a warm-water tail-withdrawal procedure was examined with the selective kappa opioid agonist U50,488, the selective mu agonist morphine, and the two mixed-action opioids butorphanol and nalbuphine. RESULTS: The steroid treatment regimens produced physiological levels of progesterone and estradiol similar to peak levels observed during the luteal phase of the menstrual cycle and physiological levels of testosterone similar to those observed in intact males. Treatment with P, P+E, or T did not alter baseline thermal nociception. P+E significantly increased the potency of U50,488 at 50 degrees C but not at 54 degrees C. Gonadal hormone treatments had little or no effect on antinociception produced by morphine, butorphanol, or nalbuphine at either temperature. CONCLUSIONS: These findings further suggest that chronic treatment with physiological levels of gonadal hormones may modulate the antinociceptive effects of U50,488 in ovariectomized rhesus monkeys. 相似文献
54.
Ariwodola OJ Crowder TL Grant KA Daunais JB Friedman DP Weiner JL 《Alcoholism, clinical and experimental research》2003,27(10):1632-1639
BACKGROUND: The physiological mechanisms underlying the behavioral and cognitive effects of ethanol are not fully understood. However, there is now compelling evidence that ethanol acts, at least in part, by modulating the function of a small group of proteins that mediate excitatory and inhibitory synaptic transmission. For example, intoxicating concentrations of ethanol have been shown to enhance GABAergic synaptic inhibition and depress glutamatergic excitatory neurotransmission in a number of brain regions. Because all of these electrophysiological studies have been performed in rodent brain slice or neuronal culture preparations, direct evidence that ethanol exerts similar effects on synaptic transmission in the primate central nervous system is lacking. METHODS: We have therefore developed methods to perform patch-clamp electrophysiological recordings from neurons in acutely prepared monkey (Macaca fascicularis) hippocampal slices. We have used these methods to compare the acute effects of ethanol on excitatory and inhibitory synaptic transmission in rat and monkey dentate granule neurons. RESULTS: Under our recording conditions, ethanol significantly potentiated gamma-aminobutyric acid type A inhibitory postsynaptic currents in both rat and monkey neurons. In addition, ethanol significantly inhibited NMDA, but not AMPA, excitatory postsynaptic currents in dentate granule neurons from both species. Notably, no significant differences were observed in any of the pharmacological properties of inhibitory or excitatory synaptic responses recorded from rat and monkey neurons. CONCLUSIONS: These data suggest that the differences in the behavioral effects of ethanol that have been observed between rats and higher-order mammals, such as monkeys and humans, may not reflect differences in the sensitivity of some of the major synaptic sites of ethanol action. Moreover, our results provide empirical evidence for the use of rodent brain slice preparations in elucidating synaptic mechanisms of ethanol action in the primate central nervous system. 相似文献
55.
Marmoset monkeys (Callithrix jacchus) with bilateral transections of the anterior temporal stem, amygdala and fornix were unable to relearn a 2-choice object discrimination first learnt prior to surgery, and were very severely impaired at relearning a concurrent object discrimination task which they had learnt and relearnt prior to surgery, indicating that they had a dense retrograde amnesia. They also had difficulty learning new visual object discriminations but were only mildly impaired on spatial learning. When tested on new learning of concurrent discriminations 8 to 10 weeks after surgery, three operated monkeys were unable to reach criterion in 400 trials while the remaining two operated monkeys performed within the normal range. The operated monkeys were subsequently shown to be impaired on acquisition of shape discriminations using black objects. These anterograde effects suggest that the impairment runs mainly in the domain of visual analysis. The monkeys also exhibited many of the features of the Klüver-Bucy syndrome. Histological analysis indicated that in addition to cutting some of the subcortical temporal lobe efferent pathways, the surgical procedures had cut the cholinergic afferents to the temporal neocortex, entorhinal cortex, and hippocampus. In a second experiment we found that treatment with the cholinergic agonist pilocarpine, which is effective in monkeys with specific cholinergic lesions, was unable to remediate the lesion-induced impairments. This suggests that transection of the non-cholinergic afferents, or the temporal lobe subcortical efferents, contributed to the behavioural syndrome and the learning and retention deficits seen in these monkeys. 相似文献
56.
Johnson H Cowey A 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,132(2):269-275
Transneuronal retrograde degeneration of retinal ganglion cells follows extensive striate cortical removal in macaque monkeys. Its extent depends on the age of the monkey at operation, post-operative survival, species and retinal eccentricity. Some studies of human patients with occipital lobe injury have found no evidence for transneuronal retrograde degeneration, suggesting that either degeneration may not occur or, if present, it is caused directly by secondary damage impinging upon the underlying white matter or the blood supply to the dorsal lateral geniculate nucleus and optic tract. We therefore studied retinal ganglion cell degeneration in three macaques in which only the striate cortex corresponding to the macular retina had been removed, thereby sparing extrastriate cortex and precluding interruption of the vascular supply to the thalamus and optic tract. There was extensive loss of ganglion cells in the central retina, corresponding to the central 10 degrees of vision. As the cortical lesion was too small to affect the thalamus or optic tract directly, the retinal degeneration must be transneuronal. Quantitative analysis showed a 65-80% loss of ganglion cells in the corresponding perifoveal retinae along the horizontal meridian. The results confirm that the loss of retinal ganglion cells following striate cortical lesions is predominantly transneuronal. 相似文献
57.
Five squirrel monkeys were trained to stable levels of performance on fixed ratio schedules of food reinforcement. N,N-dimethyltryptamine (DMT) was then injected intramuscularly prior to fixed ratio testing and the behavioral effects observed. The determination of dose-response relationships with doses of 0.0, 5.4 and 10.8 moles/kg indicated that latencies to initiate responding were an increasing function of the dose, while overall response rates, as measured from the first to the last response of the session were unaffected. When a dose of DMT which initially disrupted operant behavior was administered once daily for 36 to 38 consecutive days, tolerance was not observed to occur.This research was supported by Department of Justice Contract No. J-69-10 from the Drug Control Division, Office of Scientific Support, Bureau of Narcotics and Dangerous Drugs. Basic support of the Yerkes facility was provided by Grant RR-00165 of the Division of Research Resources, NIH. The research described in this report involved animals maintained in animal care facilities fully accredited by the American Association for Accreditation of Laboratory Animal Care. 相似文献
58.
Summary The hypothalamic oxytocin and vasopressin neurons of the monkey, Macaca fuscata, were demonstrated in Golgi-like images by a modified immunoperoxidase method. The magnocellular oxytocin and vasopressin neurons were distributed mainly in the supraoptic and paraventricular nuclei. In addition to these main nucleic, both types of magnocellular neurons were found in the accessory supraoptic nucleus, the periventricular and perifornical areas, the nucleus of the stria terminalis, the lateral hypothalamic area, and the pars interna of the globus pallidus. Magnocellular oxytocin neurons were seen immediately ventral to the anterior commissure, and parvocellular vasopressin neurons were localized in the medial portion of the suprachiasmatic nucleus. The preferential distribution of the oxytocin and vasopressin neurons was recognized not only in the supraoptic and paraventricular nuclei, but also in other areas. In all areas observed, the cytological difference between the oxytocin and vasopressin neurons could be identified. The area, of the perikarya of the vasopressin neurons was determined to be larger than that of the oxytocin neurons. Most of the axons of the oxytocin neurons issued from the perikarya, while the axons of the vasopressin neurons originated in most cases from the thick proximal dendrites. These results show that the oxytocin and vasopressin neurons are distributed in areas much broader than has hitherto been assumed, and that these two peptidergic neurons can be definitely differentiated morphologically as well as functionally.Supported by grants (No. 56440022, 56770037) from the Ministry of Education, Science, and Culture, Japan 相似文献
59.
Responding maintained in squirrel monkeys under a 10-min fixed-interval schedule of food presentation was suppressed by presenting a shock after every 30 th response (punishment). During alternate 10-min periods of the same experimental session, but in the presence of a different discriminative stimulus, responding either had no effect (extinction) or postponed delivery of an electric shock (avoidance). During sessions when the avoidance schedule was not in effect, d-amphetamine sulfate decreased punished responding. When the avoidance schedule was present during alternate 10-min periods, however, d-amphetamine (0.01–0.56 mg/kg, i.m.) markedly increased responding during punishment components. Increases in responding during avoidance components were also evident. The effects of d-amphetamine on punished responding depend on the context in which that responding occurs. 相似文献
60.
M. Magnin A. F. Fuchs 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1977,28(3-4):293-299
Summary Monkeys were trained to make visually evoked eye movements while undergoing simultaneous head rotation. Single units were recorded in the pregeniculate nucleus (PGN). PGN neurons discharged during each saccade, but there was no change in activity with horizontal head acceleration or with various combinations of head and smooth pursuit eye movements as previously described in the cat. Therefore, the anatomical homology between LGNv and PGN does not appear to have a neurophysiological basis. Neurons in the oral part of VPL or occasionally in VPI discharged as a function of head velocity but not with saccades, smooth pursuit or fixation eye movements, nor after brief light flashes or during smooth pursuit across structured backgrounds. This suggests that VPLo and VPI are only vestibular relay nuclei and not concerned with vestibular/visual or vestibular/oculomotor interactions.It is a pleasure to acknowledge the histological talents of Donna Simmons, the veterinary care provided by Stan Crossman and Margaret Price, the surgical assistance of Doug Hasund, the secretarial help of Jean Scalf, and the editorial comments of Kate Schmitt.On leave from Laboratoire de Neuropsychologie Expérimentale, INSERM U 94, 16, av. Doyen Lépine, 69500 Bron, FranceThis research was supported by grants RR00166, GM00260 and EY00745 from the National Institutes of Health, U. S. Public Health Service, and by a grant from INSERM. 相似文献