侧脑室内注射五肽胃泌素对大鼠血压和心率的影响

以动脉血压和心率作为指标，在氨基甲酸乙酯麻醉，三碘季胺酚制动，呼吸机控制呼吸的ＳＤ大鼠上，观察到侧脑室注射五肽胃泌素（Ｇ５，４μｇ）后动脉血压升高，３ｍｉｎ时达峰值，由给药前的１２．２±１．５ｋＰａ，增至１４．１±１．６ｋＰａ；心率增加，其最大值由给药前的４３５±５３．９次／ｍｉｎ，增至４１７．６±５３．２次／ｍｉｎ。而侧脑室注射生理盐水（ｐＨ和容积与Ｇ５相同）或静脉注射同样剂量的Ｇ５，对上述指标均无影响。侧脑室预先注射α受体阴断剂酚妥拉明（１０μｇ）．可部分拮抗Ｇ５对血压和心率的增加效应。结果表明Ｇ５具有中枢性升高动脉血压和心率的作用，此作用可能部分由脑内α受体介导。

Effect of Pentagastrin Injected Into Iateral Vantricle on Blood Pressure and Heart Rate in Rats

Experiments were carride out on 64 artificially ventilated SD rats anaesthetized with urethane and galllamine triethiodide immobilized.Injection on pentagastrin(G5)into the rat lateral ventricle resulted in a marded elevation in arterial blood pressure which reached its peak at 3 min(from 12.2±1.5 to 14.1±1.7 kPa),and also a significant increase in heart rate with its mazimal value being from 4.35±53.9 to 471.6±53.2 beats/min.However,no change in blood pressure and heart rate was observed when the normal saline (NS) was injection into same sites on an equal dose of G5 was injected intravenously.In addition,the increase effect of G5 on blood pressure and heart rate was partially antagonized by injection of phentolamine (α-receptor antagonist,10μg) into lateral ventricle.These findings indicate that G5 can elevate blood pressure and heart rate centrally.and its action may be porty medicated by central α-adrenoceptor.