Tanaka J, Saito H, Seto K
Department of Physiology, Kochi Medical School, Japan.
Brain Res. 1988 Oct 4;461(2):403-6. doi: 10.1016/0006-8993(88)90277-6.
Extracellular single-unit activity was recorded from phasically firing neurohypophyseal neurons (n = 41) in the hypothalamic paraventricular nucleus (PVN) of urethane-anesthetized male rats. Electrical stimulation of the subfornical organ (SFO) produced orthodromic long-duration (n = 18) or short-duration (n = 10) excitation or inhibition (n = 8) of the activity of PVN neurons. The long-duration excitatory response of about half (n = 7) the neurons (n = 15) tested was reversibly abolished by microinjection of the local anesthetic lidocaine into the median preoptic nucleus (MnPO), whereas neither the short-duration excitatory (n = 7) nor inhibitory (n = 6) responses were affected. These results suggest that the SFO efferents through the MnPO to the PVN may transmit the neuromodulatory signals which evoke long-duration increases in the excitability of putative vasopressin (VP)-secreting neurons in the PVN.
在氨基甲酸乙酯麻醉的雄性大鼠下丘脑室旁核（PVN）中，对相位性放电的神经垂体神经元（n = 41）进行细胞外单单位活动记录。电刺激穹窿下器（SFO）可产生PVN神经元活动的顺向长时程（n = 18）或短时程（n = 10）兴奋或抑制（n = 8）。向视前正中核（MnPO）微量注射局部麻醉剂利多卡因，可使约一半（n = 7）经测试的神经元（n = 15）的长时程兴奋反应可逆性消失，而短时程兴奋（n = 7）和抑制（n = 6）反应均不受影响。这些结果表明，SFO经MnPO至PVN的传出纤维可能传递神经调节信号，这些信号可引起PVN中假定的血管加压素（VP）分泌神经元兴奋性的长时程增加。
