Effects of anaesthesia and sinoaortic denervation (SAD) on the hypotensive action of , ketanserin were studied in rats. It was found that the dose-effect curves of kelanserin on blood pressure were the same between SAD and sham-operated rats under anaesthesia. However, in concious free ly moving rats, SAD sharpened the dose-effect curves. It is concluded that the lack of hypotensive effect of ketanserin in conscious normotensive animals is due in large part to the integrity of the arterial baroreflex.

The contents of ir-arg-vasopressin (ir-AVP) and ir-?-endorphin (ir-?-EP) in plasma, anterior pituitary (AP), posterior pituitary (PP), oblongata (OB) and hypothalamus (HP) were measured by radioimmunoassay after sinoaortic denervation (SAD) in rats. It was showed that the ir-AVP contents in OB and ir-?-EP contents in AP, PP and OB were significantly elevated 1 d after (SAD) (P

The pharmacokinetics of thyrotropirrreleasing hormone (TRH) made in China was studied in rabbits. TRH concentrations in plasma, urine and various tissues were measured by RIA. After intravenous injection of TRH, the plasma concentration-time curve was shown to fit a two compartment open model with the following pharmacokinetic parameters: 0.8 mg/kg, T1/2?=0.551 min, T1/2? = 9.374 mm, VI = 3.018 ml/kg, Vb = 22.659 ml/kg and AUC = 0.479g. L-1. m-1; 2.0mg/kg, T1/2? = 0.629 mm, T1/2?= 9.734 min, VI = 5.135 ml/kg, Vt = 28.848 ml/kg, and AUC = 0.962g. L-1. m-1; 5.0mg/kg, T1/2? =0.720 min, T1/2?= 10.738 min, VI = 6.120 ml/kg, Vb = 31.928 ml/kg and AUC=2.540 g. L-1. m-1. TRH was distributed widely in tissues and concentrated mainly in the kidney and pituitary. TRH was eliminated partly by the kidney and 21.9% was excreted within 2h after intravenous injection.