Jackson G L, Kuehl D
Department of Veterinary Biosciences, University of Illinois, Urbana, IL 61802, USA.
Reprod Suppl. 2002;59:15-24.
The frequency and amplitude of GnRH and LH pulses are variable and controlled by both external environmental and internal physiological factors. However, the specific neurochemical-neuroanatomical pathways that control the basal pulsatile and surge patterns, and mediate responses to environmental and physiological factors are poorly defined. The gamma-aminobutyric acid (GABA) secretory system is one of several that modulate GnRH and LH. GABA release in the preoptic area (POA) preceding the onset of oestrogen-induced LH surges changes in a pattern that is inverse to LH release. Application of GABA agonists or antagonists to either the POA or mediobasal hypothalamus disrupts LH secretion. Observations that application of GABA(B) agonists to either the POA or mediobasal hypothalamus rapidly reverses the negative feedback effect of oestrogen or testosterone on LH lead the authors to suggest that GABA(B) receptors have an important role in regulating LH secretion in sheep.
促性腺激素释放激素（GnRH）和促黄体生成素（LH）脉冲的频率和幅度是可变的，受外部环境和内部生理因素的控制。然而，控制基础脉冲式和激增模式并介导对环境和生理因素反应的具体神经化学 - 神经解剖学途径尚不清楚。γ-氨基丁酸（GABA）分泌系统是调节GnRH和LH的几个系统之一。雌激素诱导的LH激增开始前，视前区（POA）的GABA释放模式与LH释放模式相反。将GABA激动剂或拮抗剂应用于POA或下丘脑内侧基底部会扰乱LH分泌。将GABA（B）激动剂应用于POA或下丘脑内侧基底部可迅速逆转雌激素或睾酮对LH的负反馈作用，这一观察结果使作者认为GABA（B）受体在调节绵羊LH分泌中起重要作用。
