共查询到20条相似文献,搜索用时 15 毫秒
1.
The functional role of 5-HT1 receptors in the memory trace retrieval was investigated in amygdala (AM), central gray substance of midbrain (CGS) and frontal cortex. There is used the passive avoidance response in the rat. The decrease of 5-HT1 binding sites in AM and CGS was revealed for the rats with retention of the passive avoidance response. The binding of 3H-5-HT in AM was found two sets of binding sites. It was concluded, that 5-HT1 receptors of AM and CGS are involved in learning processes either in the moment of the memory trace retrieval or immediately after it. 相似文献
2.
Effects of aspartate (2 · 10–5 M), substance P (10–7–10–8 M), and serotonin (5-hydroxytryptamine, 5-HT; 5 · 10–5 M) on the background activity of neurons in the central gray substance (CGS) were studied on slices of the rat midbrain. Aspartate and substance P (transmitters of nociceptive signals), and 5-HT (modulator of transmission of nociceptive influences) were found either to facilitate or to depress the activity of CGS neurons. The predominant effect of substance P or 5-HT applications to neurons of the dorsal CGS part was facilitation, and to neurons of the ventral CGS part, inhibition. The effects of aspartate application on studied CGS neurons were of varying nature, but inhibitory effects were found to prevail.The findings support our earlier hypothesis that assigned the studied neurons to spontaneously discharging inhibitory CGS interneurons, which control the activity of efferent CGS neurons. The role of tested substances in the regulation of CGS neuronal activity and the antinociceptive CGS effects is discussed.Neirofiziologiya/Neurophysiology, Vol. 25, No. 5, pp. 354–362, September–October, 1993. 相似文献
3.
Estrogen plays an important role during differentiation of midbrain dopaminergic neurons. This is indicated by the presence of estrogen receptors and the transient expression of the estrogen-forming enzyme aromatase within the dopaminergic cell groups. We have previously shown that estrogen regulates the plasticity of dopamine cells through the stimulation of neurite growth/arborization. In this study, we have analyzed the capability of estrogen to influence the activity of developing mouse dopamine neurons. The expression of tyrosine hydroxylase (TH) was assessed by competitive RT-PCR and Western blotting. The developmental expression of TH in the ventral midbrain was studied from embryonic day 15 until postnatal day 15 and revealed highest TH levels early postnatally. This profile coincides with the transient aromatase expression in this brain area. Using cultured midbrain cells, we found that estrogen increased TH mRNA/protein levels. The application of the estrogen receptor antagonist ICI 182,780 resulted in a complete inhibition of estrogen effects. To verify these data in vivo, fetuses were exposed in utero from E15 until birth to the aromatase inhibitor CGS 16949A or to CGS supplemented with estrogen. CGS caused a robust reduction in TH mRNA/protein levels in the midbrain, which could be restored by estrogen substitution. Taken together, our data strongly suggest that estrogen controls dopamine synthesis in the developing nigrostriatal dopaminergic system and support the concept that estrogen is implicated in the regulation of ontogenetic steps but also in the function of midbrain dopamine neurons. 相似文献
4.
Wolfgang Walkowiak 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1988,164(1):31-41
Summary Male fire-bellied toads,Bombina bombina, are stimulated into calling by conspecific mating calls. They tend to synchronize their activity with other calling individuals, which leads to antiphonal calling. Behavioral physiological experiments revealed the existence of two different auditory filter systems which influence this acoustic behavior. One filter system is tuned to the recognition of conspecific mating calls, the other is part of a circuit that controls an acoustic jamming avoidance reaction. The two filter systems differ in several properties: filter bandwidth, threshold, and time constant. Neurophysiological recordings in the midbrain and the thalamus show that the filter characteristics can be explained by the coding properties of auditory neurons in these two brain nuclei. 相似文献
5.
Acute "pontine" cats were submitted to abrupt increases in blood pressure induced by a transient obstruction of the lower thoracic aorta. This stimulation regularly provoked a complex electrocortical response. The first part of it, which occured 12 sec after the beginning of the pressure rise, consisted of an activation reaction accompanied by dilatation of the pupils and tonic contraction of the lower back muscle and preceded by arrest of respiration. The activation reaction and pupillary dilatation were absent in the cats with a brain stem section at the junction between the pons and the mesencephalon. The effects on the cerebrum are attributed to a passive increase in blood flow which is effective on ECoG and pupils only when the midbrain is connected to the brain. The second and third parts of the response, a burst of slow waves followed by a flattening of the record, were dependent of the hypotension which followed the end of the blood pressure rise. They were preserved in the cats with a lesion of the junction between the pons and the mesencephalon. They are attributed to a relative ischemia of the brain. 相似文献
6.
A N Talalaenko 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1989,39(6):1124-1128
Dopamine and serotonin microinjection in the dorsal raphe nucleus of rats does not influence the alarm state in the test of "threatening situation" avoidance, but increases or weakens the state of alarm in the rest of "illuminated site" avoidance. Local injection of GABA in this midbrain formation weakens the alarm state in the test of "threatening situation" avoidance but is not effective in the test of "illuminated site" avoidance. Chemical stimulation of the raphe nucleus by glutaminic acid does not influence the two different experimentally modelled states of alarm, but modulates the mechanisms controlling the instinct of darkness preference by rats. 相似文献
7.
V L Bianki E B Filippova S E Murik 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1985,35(2):261-266
Hemispheric asymmetry of "emotional resonance" elaborated by the method of P.V. Simonov was studied in Wistar rats. Inactivation of hemispheres was carried out by means of spreading depression. When using as "victims" and "recipients" the animals of the same sex, lateralization of emotional resonance was found to depend upon the velocity of reaction elaboration. In rats rapidly elaborating avoidance reaction the right hemisphere dominated during its performance and so did the left one in animals learning after additional training. When using the animals of different sex as "victims" and "recipients", the right hemisphere dominated in "emotional resonance" performance. Hemispheric asymmetry of "emotional" resonance was more expressed in males than in females. 相似文献
8.
P A Nerush 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1988,38(6):1152-1157
Formation of experimental neurosis in rats was accompanied in 64% of animals by development of amnesia of conditioned reaction of passive avoidance. Disturbance of mnestic processes was manifested by a change in free amino acids pool including the acids with neurotransmitter properties (GABA, glutamate, glycine). An increase of GABA and glycine content was found in the frontal cortex and an increase of glutamate and GABA--in the hippocampus and striate body. Substance P (125 mkg/kg) administered intraperitoneally against the background of a developed neurosis, produced in 80% of cases an antiamnestic action, accompanied by a statistically significant decrease of GABA content in the frontal cortex, hippocampus and midbrain, and an increase of glutamate in the midbrain. The level of taurine decreased in the frontal cortex, hippocampus and striate body, and increased in the midbrain. Threonine content increased in the striate body and midbrain; there was an increase of taurine, serine and glycine in the midbrain and of glycine in the striate body. 相似文献
9.
L L Pragina A N Inozemtsev N A Tushmalova 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1992,(6):84-88
The results of effect of some new synthesized psychotropic drugs of nootropic series on rats' behavior in "open field" are given. The increase of locomotive activity and decrease of emotional tension correlated with the rise of rats' ability to learning during working-out of avoidance reaction in shuttle-box, e.i. conditionally reflectory memory. It has been concluded that the study of dynamics of behavioral reactions in "open field" may be used for testing of new synthesized psychotropic drugs of nootropic series. 相似文献
10.
Kaplun AP Burdelev OO Ivanova NN Krasnopol'skiĭ IuM Shvets VI 《Bioorganicheskaia khimiia》2000,26(1):68-77
Cerebroside sulfate (CGS) was found to be capable of inhibiting complement-dependent hemolysis. The activity dependence of CGS-containing liposomes on their composition was studied. Mixtures of CGS with phosphatidylethanolamine, phosphatidylserine, sphingomyelin from cattle brain, cerebroside from cattle spinal cord (CG), and egg yolk phosphatidylcholine (ePC) were investigated. In the case of binary CGS/ePC mixtures, the antihemolytic activity varied nonlinearly with an increase in the mass part of CGS: it sharply increased with an increase in the CGS part from 0.3 to 0.5 and decreased by 20-30% of the maximum value with an increase in the CGS part from 0.9 to 1. On the basis of these experiments, the optimum distance between the charged groups of CGS was estimated to be 0.92-1.6 nm. In the ternary compositions of 4:3:3 CGS/ePC/polar lipid, only CG increased the activity of liposomes as compared to that of liposomes from the 4:6 CGS/ePC. The preliminary incubation of CGS-containing liposomes with complement decreased hemolysis more effectively than incubation with other components of the hemolytic system. This suggests that the interaction of CGS-containing liposomes with the complement proteins is responsible for their antihemolytic activity. 相似文献
11.
A. P. Kaplun O. O. Burdelev N. N. Ivanova Yu. M. Krasnopol’skii V. I. Shvets 《Russian Journal of Bioorganic Chemistry》2000,26(1):60-68
Cerebroside sulfate (CGS) was found to be capable of inhibiting complement-dependent hemolysis. The activity dependence of
CGS-containing liposomes on their composition was studied. Mixtures of CGS with phosphatidylethanolamine, phosphatidylserine,
sphingomyelin from cattle brain, cerebroside from cattle spinal cord (CG), and egg yolk phosphatidylcholine (ePC) were investigated.
In the case of binary CGS/ePC mixtures, the antihemolytic activity varied nonlinearly with an increase in the mass part of
CGS: it sharply increased with an increase in the CGS part from 0.3 to 0.5 and decreased by 20–30% of the maximum value with
an increase in the CGS part from 0.9 to 1. On the basis of these experiments, the optimum distance between the charged groups
of CGS was estimated to be 0.92–1.6 nm. In the ternary compositions of 4:3:3 CGS/ePC/polar lipid, only CG increased the activity
of liposomes as compared to that of liposomes from the 4:6 CGS/ePC. The preliminary incubation of CGS-containing liposomes
with complement decreased hemolysis more effectively than incubation with other components of the hemolytic system. This suggests
that the interaction of CGS-containing liposomes with the complement proteins is responsible for their antihemolytic activity. 相似文献
12.
E I Popova I A Koptelova 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1979,29(6):1123-1132
A method has been elaborated of training the human subjects to avoid electric shocks by overcoming the "fear" caused by a warning signal. A previously elaborated differentiated conditioned skin-galvanic response (SGR) to a sound stimulus served as a criterion of the emotional reaction. The SGR was projected on an oscilloscope screen. The electric shock was automatically delivered at the moment when the amplitude of the conditioned SGR exceeded the level marked on the screen. The subject was instructed, by overcoming the "fear", to retain the SGR amplitude below the level. If the subject succeeded in overcoming the conditioned SGR to the signal, the shock was not delivered. Since, the suppression of the conditioned SGR served as a "instrument" of avoidance and became consolidated as a habit based on a positive reinforcement. The subjects developed a stable attraction to repetition of training sessions in which they learned to suppress the "anxiety" caused by a signal of "threat". 相似文献
13.
In previous studies, we have shown that the inactivation of the adenosine A2A receptor exacerbates chronic cerebral hypoperfusion-induced white matter lesions (WMLs) by enhancing neuroinflammatory responses. However, the molecular mechanism underlying the effect of the adenosine A2A receptor remains unknown. Recent studies have demonstrated that cystatin F, a potent endogenous cysteine protease inhibitor, is selectively expressed in immune cells in association with inflammatory demyelination in central nervous system diseases. To understand the expression of cystatin F and its potential role in the effect of A2A receptor on WMLs induced through chronic cerebral hypoperfusion, we investigated cystatin F expression in the WMLs of A2A receptor gene knockout mice, the littermate wild-type mice and wild-type mice treated daily with the A2A receptor agonist or both CGS21680 and A2A receptor antagonist CGS21680 after chronic cerebral hypoperfusion. The results of quantitative-PCR and western blot analysis revealed that cystatin F mRNA and protein expression were significantly up-regulated in the WMLs after chronic cerebral hypoperfusion. In addition, cystatin F expression in the corpus callosum was significantly increased in A2A receptor gene knockout mice and markedly decreased in mice treated with SCH58261 on both the mRNA and protein levels. Additionally, CGS21680 counteracted the attenuation of cystatin F expression produced by SCH58261 after chronic cerebral hypoperfusion. Moreover, double immunofluorescence staining revealed that cystatin F was co-localized with the activated microglia marker CD11b. In conclusion, the cystatin F expression in the activated microglia is closely associated with the effect of the A2A receptors, which may be related to the neuroinflammatory responses occurring during the pathological process. CGS21680相似文献
14.
Selenium (Se) can be assimilated and volatilized via the sulfate assimilation pathway. Cystathionine--synthase (CGS) is thought to catalyze the synthesis of Se-cystathionine from Se-cysteine, the first step in the conversion of Se-cysteine to volatile dimethylselenide. Here the hypothesis was tested that CGS is a rate-limiting enzyme for Se volatilization. Cystathionine--synthase from Arabidopsis thaliana (L.) Heynh. was overexpressed in Indian mustard [Brassica juncea (L.) Czern & Coss], and five transgenic CGS lines with up to 10-fold enhanced CGS levels were compared with wild-type Indian mustard with respect to Se volatilization, tolerance and accumulation. The CGS transgenics showed 2- to 3-fold higher Se volatilization rates than wild-type plants when supplied with selenate or selenite. Transgenic CGS plants contained 20–40% lower shoot Se levels and 50–70% lower root Se levels than the wild type when supplied with selenite. Furthermore, CGS seedlings were more tolerant to selenite than the wild type. There were no differences in Se accumulation or tolerance from selenate, in agreement with the earlier finding that selenate-to-selenite reduction is rate-limiting for selenate tolerance and accumulation. In conclusion, CGS appears to be a rate-limiting enzyme for Se volatilization. Overexpression of CGS offers a promising approach for the creation of plants with enhanced capacity to remove Se from contaminated sites in the form of low-toxic volatile dimethylselenide.Abbreviations CGS cystathionine--synthase - DMSe dimethylselenide - SeCys selenocysteine - WT wild type 相似文献
15.
L V Simutenko N L Iastrebtsova T A Leontovich 《Biulleten' eksperimental'no? biologii i meditsiny》1979,87(3):211-214
The changes in the blood serum cholesterol and triglyceride content were studied or rabbits of both sexes during reactions of self-stimulation and avoidance. Self-stimulation was accompanied by a significant decrease in the blood serum cholesterol and triglyceride content. During the reaction of avoidance the character of the cholesterol changes varied. The reaction of avoidance of the "agression" type was accompanied by elevated blood serum cholesterol content, whereas the reaction of the "fear" type was associated with a decrease in its content. The maximal changes in the cholesterol and triglyceride content as compared to the initial level were observed in all types of the reactions 15--30 minutes following stimulation. 相似文献
16.
The effects of the benzodiazepine antagonist CGS 8216 (2-phenylpyrazolo[4,3-c]quinoline-3(5H)-one) were examined in a thirsty rat conflict test in the presence and absence of pentobarbital. CGS 8216 (2.5-10 mg/kg i.p.) did not affect nonpunished responding, but doses of 5 and 10 mg/kg significantly reduced the rate of punished responding (i.e., the number of 3 second drinking episodes in a "shock" contingency). However, a dose of CGS 8216 which did not significantly alter punished responding (2.5 mg/kg) antagonized the anticonflict actions of pentobarbital. These observations suggest that while high doses of CGS 8216 may elicit an "anxiogenic" response in rodents, lower doses of CGS 8216 antagonize the anticonflict actions of a compound which has been shown to enhance benzodiazepine affinity in vitro. These data imply that the anticonflict actions of pentobarbital may be mediated through benzodiazepine receptors. 相似文献
17.
P Van Roey K A Bullion Y Osawa L J Browne R M Bowman D G Braun 《Journal of enzyme inhibition》1991,5(2):119-132
The crystal and molecular structures of 4-(5,6,7,8-tetrahydroimidazo[1,5-a]pyridin-5-yl)benzonitrile hydrochloride (CGS 16949A) and bis(p-cyanophenyl)imidazo-1-yl methane hemisuccinate (CGS 18320B) have been determined as part of structure-activity relationship studies of non-steroidal aromatase inhibitors. CGS 18320B crystallizes with two inhibitor molecules in the asymmetric unit that are similar in conformation. The cyanophenyl groups and the imidazole moieties in the CGS 18320B molecules display a propellor-like arrangement. The orientation of the imidazole ring in CGS 16949A, which is constrained by the piperidine ring, differs by about 80 degrees from the orientations in both CGS 18320B molecules. The conformations of both compounds are consistent with the proposed model (Banting et al. (1988) J. Enz. Inhibit., 2, 216) for inhibitor binding by positioning of the cyanophenyl group in the steroid A-ring binding site and interaction of the imidazole nitrogen with the iron of the haem. 相似文献
18.
19.
The transsulfuration enzyme cystathionine gamma-synthase (CGS) catalyses the pyridoxal 5'-phosphate (PLP)-dependent gamma-replacement of O-succinyl-L-homoserine and L-cysteine, yielding L-cystathionine. The crystal structure of the Escherichia coli enzyme has been solved by molecular replacement with the known structure of cystathionine beta-lyase (CBL), and refined at 1.5 A resolution to a crystallographic R-factor of 20.0%. The enzyme crystallizes as an alpha4 tetramer with the subunits related by non-crystallographic 222 symmetry. The spatial fold of the subunits, with three functionally distinct domains and their quaternary arrangement, is similar to that of CBL. Previously proposed reaction mechanisms for CGS can be checked against the structural model, allowing interpretation of the catalytic and substrate-binding functions of individual active site residues. Enzyme-substrate models pinpoint specific residues responsible for the substrate specificity, in agreement with structural comparisons with CBL. Both steric and electrostatic designs of the active site seem to achieve proper substrate selection and productive orientation. Amino acid sequence and structural alignments of CGS and CBL suggest that differences in the substrate-binding characteristics are responsible for the different reaction chemistries. Because CGS catalyses the only known PLP-dependent replacement reaction at Cgamma of certain amino acids, the results will help in our understanding of the chemical versatility of PLP. 相似文献
20.
Due to the overexploitation of farming, as well as habitat destruction, the wild population of Chinese giant salamander (CGS) Andrias davidianus, a species with seven genetically distinct lineages, has decreased by over 80% in the past 70 years. Traditional survey methods have proven to be unsuitable for finding this rare and elusive species. We evaluated the efficacy of environmental DNA (eDNA) sampling to detect CGS indirectly from its aquatic environment. We developed several species-specific primer sets; validated their specificity and sensitivity; and assessed their utility in silico, in the laboratory, and at two field sites harboring released farm-bred CGS. We detected the presence of CGS DNA by using polymerase chain reaction and Sanger sequencing. We also sequenced an amplicon mixture of seven haplotype-represented samples using high-throughput sequencing. Our eDNA methods could detect the presence of CGS at moderate densities reported across its range, proving them as a cost-effective way to establish broad-scale patterns of occupancy for CGS. In addition, our primers enabled the detection of mitochondrial lineage mixture or introduced individuals from geographically isolated populations of CGS. 相似文献