Reference

On the measurement of vascular and respiratory smooth muscle responses in vitro

On the measurement of vascular and respiratory smooth muscle responses in vitro. Hooker, Carol S.; Calkins, Patricia J.; Fleisch, Jerome H. (Div. Pharmacol. Res., Eli Lilly and Co., Indianapolis, Indiana, USA). Blood Vessels, 14(1), 1-11 (English) 1977. CODEN: BLVSAB. DOCUMENT TYPE: Journal CA Section: 2 (Hormone Pharmacology) Section cross-reference(s): 9 The action of drugs on circular smooth muscle from rabbit renal artery, renal vein, mesenteric vein, inferior vena cava, guinea pig bronchus, and mouse trachea was studied. All the blood vessels contracted to norepinephrine bitartrate (I) [51-40-1], histamine-2HCl [56-92-8], and KCl. The veins, unlike the renal artery, did not respond maximally to KCl and did not contract at all in response to serotonin creatinine sulfate [971-74-4]. The guinea pig bronchi was contracted by carbachol [51-83-2], histamine, and KCl and relaxed by isoproterenol. The mouse trachea was contracted maximally by carbachol, was not contracted by histamine, and was contracted to 50% of max. in response to KCl. Thus, std. isolated tissue baths can be inexpensively adapted for the study of relatively small blood vessels and airways (.apprx.1 mm in diameter).

H1- and H2-receptor mediated responses to histamine on contractility and cyclic AMP of atrial and papillary muscles from guinea pig hearts

H1- and H2-receptor mediated responses to histamine on contractility and cyclic AMP of atrial and papillary muscles from guinea pig hearts. Reinhardt, D.; Schmidt, U.; Brodde, O. E.; Schuemann, H. J. (Pharmacol. Inst., Univ. Essen, Essen, Ger.). Agents Actions, 7(1), 1-12 (English) 1977. CODEN: AGACBH. DOCUMENT TYPE: Journal CA Section: 2 (Hormone Pharmacology) In papillary muscle isolated from guinea pigs, histamine-2HCl (I-2HCl) [56-92-8] elicited pos. inotropic responses which were antagonized by burimamide but not by promethazine. The stimulation of H2-receptors increased cyclic AMP (II) [60-92-4] levels. At 10-5M I, the maximal increase in II preceded the max. in contractility. The mech. and biochem. responses to I were potentiated by the phosphodiesterase inhibitor papaverine, but antagonized by burimamide. On the left guinea pig atrium contg. H1-receptors the inotropic response to I (10-5M) was not accompanied by increases in II at stimulation frequencies of 0.5 and 2 Hz, resp. In addn., in the presence of papaverine (3 .times. 10-5M) no change in the II level occurred after application of I. Papaverine by itself, however, concomitantly increased contractility and II at a stimulation frequency of 0.5 Hz. In contrast, at 2 Hz papaverine increased only II leaving the contractility unchanged. On the right guinea pig atrium the mediation of the pos. chronotropic response to I by H2-receptors did not lead to a concomitant increase in II. Also, in the presence of papaverine, I had no influence on the II level. However, papaverine potentiated the cardioacceleration produced by I. Apparently, the mediation of the inotropic effect due to stimulation of H2 receptors by I is assocd. with an increase of II, whereas that of H1 receptors is not.