电刺激猫下丘脑室旁核引起的增压反应

作者用经氯醛糖、乌拉坦麻醉，肌肉麻痹，人工呼吸的成年家猫２４只。用０．１～０．５ｍＡ，８０Ｈｚ，０．２ｍ的方波脉冲电刺激下丘脑室旁核（ＰＡ）１２秒（ｎ＝９），引起显著的血压增高反应。２２个最大反应位点多位于ＰＡ的后部背内侧份，其中１１个位点伴心率加快１７个位点伴心率减慢１４个位点心率无变化，且均位于ＰＡ的前部。电解损毁双侧孤束核（ＮＴＳ）尾侧半（ｎ＝５）后，电刺激ＰＡ引起的增压反应和心率改变与损毁前无显著性差异，以上结果表明，ＰＡ是调节心血管活动的重要中抠之一；ＮＴＳ可能不参与电刺激ＰＡ引起的增压反应。

The Pressor Response Induced by Electrical Stimulation of Hypothalamic Paraventricular Nucleus in the Cat

The experiments were perbrmed on 24adult cats anesthetized with chloralose and urethane,paralyzed and artificially ventilated.Electrical stimula-tion of the hypothalamic paraventricular nucleus(PA)with a 12s train of 0.1 0. 5 mA and 0. 2ms squarewave pulses at a frequency of 80 Hz induced a markedincrease in arterial blood pressure(n=19).The 22points stimulated with maximum responses were clus-tered in the posterior dorsomedial part of the PA,among them 11 points were associated with an increasein heart rate and 7 adecrease.The remaining 4 pointswere associated with no change of heart rate,and situ-ated in the anterior part of the PA. Electrolytic lesionof bilateral caudal half of the nucleus of solitary tract (NTS)had no singnificant effect on cardiovascular re-sponses elicited from electric stimulation of the PA(n=5).The results suggest that the PA is one of theimportant centers regulating cardiovascular activity;the NTS may not be involved in the PA pressor re-sponse.