摘要
已证明脑神经递质GABA可促进下丘脑正中隆起LHRH神经元末梢的释放功能,这一作用可能通过抑制某些抑制性神经递质或调质释放而实现。本研究旨在观察作为体内循环调节肽的心钠素在大鼠脑内的分布,对LHRH释放的影响及对GABA调节LHRH释放的中介作用。实验结果发现:(1)雄性大鼠不同脑区心钠素的含量不同,其中以下丘脑正中隆起组织含量最高;(2)不同浓度的心钠素(10^(-8)-10^(-6)mol/L)可显著抑制LHRH从下丘脑正中隆起释放,并呈现剂量反应关系。(3)GABA(10^(-6)mol/L组)可显著抑制心钠素的释放;GABA的这一抑制作用可被GABA受体拮抗剂荷包牡丹碱(Bicuculline)完全反转。上述结果提示心钠素参与调节下丘脑正中隆起(ME)LHRH神经元末梢的释放机能,它亦可能介导GABA对下丘脑正中隆起LHRH的调节作用。
It has been found that GABA is able to stimulate the release of LHRH from hypothalamus probably through the disposal of the effect of inhibitory factors. This study observed the distribution of ANP in the brain of rats and the mediation of ANP in the effect of GABA on LHRH release from median eminence of male rat.The result showed that 1) the distribution of ANP was as follow: 80.4 ± 2.9 in the cerebral cortex, 547.1±80.5 in the brain stem, 564.1±80.5 in the hypothalamus, 280.4±34.4 in the preoptic area, 1187.5±162.4 in the median eminence and 155.3±14.0 in the pituitary gland (pg/mg tissue). ANP was present extensively in the brain of rats and the content of ANP was highest in the ME and lowest in the cerebral cortex; 2) ANP at different concentrations (10-6-10-8 Mol/L) were added to the static incubation system of ME, then the samples were collected after 10 min. The content of LHRH was measured by EL1SA. ANP could obviously inhibit LHRH release from ME in a dose-dependent manner; 3) GABA (10-6 Mol/L) inhibited ANP release from the ME. The content of ANP was 283.1 ±23.4 in control group, 19.2±1.8 in GABA group and 433.3 ±31.9 in bicucullin (10-6 Mol/L) group (pg/100μl). The above observation indicated that there were significantly different contents of ANP in the brain, the highest was in ME. It may regulate LHRH release from ME by acting as a modulator in the influence of GABA on LHRH release.
出处
《动物学报》
SCIE
CAS
CSCD
1992年第2期187-193,共7页
ACTA ZOOLOGICA SINICA
基金
国家计划生育委员会
国家人事部
世界卫生组织人类生殖特别规划署资助
关键词
LHRH
下丘脑
心钠素
Gamma-Aminobutyric acid (GABA), Alrial natriuretic polypeptide (ANP), Lutcinizing hormone release hormone(LHRH), Median eminence (EM), Rat.
