Pu S, Kalra P S, Kalra S P
University of Florida Brain Institute, Gainesville, FL 32610, USA.
Brain Res. 1998 Oct 19;808(2):310-2. doi: 10.1016/s0006-8993(98)00821-x.
Since nitric oxide (NO) is implicated in the neuroendocrine control of luteinizing hormone-releasing hormone (LHRH) secretion and sexual behavior which show diurnal variations, we monitored cGMP levels (an index of NO activity) in the extracellular compartment of the medial preoptic area (MPOA) using microdialysis. It was observed that MPOA cGMP levels rose significantly in the afternoon in both castrated and intact male rats, thereby suggesting the existence of a diurnal rhythm in MPOA cGMP/NO efflux which may participate in eliciting the well-known diurnal variations in LHRH neuronal activity and male sexual behavior.
由于一氧化氮（NO）参与促黄体生成激素释放激素（LHRH）分泌和性行为的神经内分泌控制，而这两者均呈现昼夜变化，我们使用微透析技术监测了内侧视前区（MPOA）细胞外区室中的环磷酸鸟苷（cGMP）水平（NO活性指标）。结果发现，去势和未去势雄性大鼠的MPOA中cGMP水平在下午均显著升高，这表明MPOA中cGMP/NO外流存在昼夜节律，这可能参与引发LHRH神经元活动和雄性性行为中众所周知的昼夜变化。
