Masson D B, Fitts D A
Department of Psychology, University of Washington, Seattle 98195.
Behav Neurosci. 1989 Aug;103(4):873-80. doi: 10.1037/h0092456.
These experiments were conducted to test whether drinking to ip captopril or to intraventricular carbachol requires an intact fiber system from the ventral subfornical organ (SFO). Wire-knife cuts were made through the wall of the third ventricle ventral to the SFO. Control rats had either sham lesions or histologically identified missed cuts. Rats with good cuts (a) drank less than either control group after ip injections of 4 mg/kg captopril, (b) drank normal amounts of 0.3 M NaCl solution when captopril was placed in the drinking water at 0.1 mg/ml, (c) drank less water but a normal amount of saline after 6 mg/kg captopril ip and 10 mg/kg furosemide diuretic ip, and (d) drank normal amounts of water after lateral ventricular injections of 1.2 or 4 nmol of carbachol. The results of the captopril experiments confirm predictions based on studies of SFO lesions and suggest that captopril causes water, but not saline, drinking via an angiotensin-related mechanism acting at the SFO. The carbachol experiment indicates either that the SFO is not a unique receptor site for ventricular carbachol or that the fibers mediating this response do not require the pathways through the ventral pole of the SFO.
进行这些实验是为了测试腹腔注射卡托普利或脑室内注射卡巴胆碱引起的饮水行为是否需要来自腹侧穹窿下器官（SFO）的完整纤维系统。用线刀在SFO腹侧的第三脑室壁上进行切割。对照大鼠要么接受假损伤，要么进行组织学鉴定的漏切。切割良好的大鼠：（a）腹腔注射4mg/kg卡托普利后，饮水量比任何一个对照组都少；（b）当饮用水中卡托普利浓度为0.1mg/ml时，饮用正常量的0.3M NaCl溶液；（c）腹腔注射6mg/kg卡托普利和10mg/kg速尿利尿剂后，饮水减少但生理盐水饮用量正常；（d）侧脑室注射1.2或4nmol卡巴胆碱后，饮水量正常。卡托普利实验的结果证实了基于SFO损伤研究的预测，并表明卡托普利通过作用于SFO的与血管紧张素相关的机制引起饮水，但不引起生理盐水饮用。卡巴胆碱实验表明，要么SFO不是脑室内卡巴胆碱的独特受体部位，要么介导这种反应的纤维不需要通过SFO腹侧极的通路。
