Tanaka J, Kaba H, Saito H, Seto K
Exp Brain Res. 1986;62(3):509-14. doi: 10.1007/BF00236029.
Twenty-three neurons in the region of the subfornical organ (SFO) were antidromically activated by electrical stimulation of the hypothalamic paraventricular nucleus (PVN) in male rats under urethane anesthesia. Microiontophoretically (MIPh) applied angiotensin II (AII) excited the activity of all units in the region of the SFO and the effect of AII was blocked by MIPh applied saralasin (Sar), an AII antagonist, but not by atropine (Atr), a muscarinic antagonist. In these units, 12 were also excited by MIPh applied acetylcholine (ACh) while 11 were not affected and the effect of ACh was attenuated by not only MIPh applied Atr, but also Sar, suggesting that not only neurons specific for AII, but also neurons sensitive to both AII and ACh project to the PVN in the region of the SFO. Intravenously administered AII excited the activity of both types of units in the region of the SFO. Microinjected AII or ACh into the region of the SFO excited the activity of putative vasopressin (VP)-secreting units in the PVN. These results suggest that neurons projecting to the PVN in the region of the SFO may act to enhance the activity of putative VP-secreting neurons in the PVN in response to circulating AII.
在乌拉坦麻醉的雄性大鼠中，通过电刺激下丘脑室旁核（PVN）逆向激活了穹窿下器（SFO）区域的23个神经元。微量离子电泳（MIPh）施加的血管紧张素II（AII）兴奋了SFO区域所有单位的活动，AII的作用被MIPh施加的AII拮抗剂沙拉新（Sar）阻断，但未被毒蕈碱拮抗剂阿托品（Atr）阻断。在这些单位中，12个也被MIPh施加的乙酰胆碱（ACh）兴奋，而11个不受影响，ACh的作用不仅被MIPh施加的Atr减弱，也被Sar减弱，这表明不仅有对AII特异的神经元，而且对AII和ACh都敏感的神经元投射到SFO区域的PVN。静脉注射AII兴奋了SFO区域两种类型单位的活动。向SFO区域微量注射AII或ACh兴奋了PVN中假定的血管加压素（VP）分泌单位的活动。这些结果表明，投射到SFO区域PVN的神经元可能在响应循环中的AII时增强PVN中假定的VP分泌神经元的活动。
