Characterization of muscarinic receptors mediating the contraction of the urinary detrusor muscle in cynomolgus monkeys and guinea pigs.

We have characterized in vitro the muscarinic receptors mediating the contraction of the detrusor muscle in Cynomolgus monkeys and guinea pigs using carbachol as the agonist and 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP, M3-selective), methoctramine (M2-selective) and pirenzepine (M1-selective) as the antagonists. Carbachol induced a concentration-dependent contraction of the detrusor muscle of monkey and guinea pig yielding similar pD2 values of 6.67+/-0.

Endothelium-dependent basilar and aortic vascular responses in normotensive and coarctation hypertensive rats.

The responsiveness of acetylcholine (ACh), nitroglycerin (NG) and norepinephrine (NE) (aorta only) in both basilar arteries (BA) and thoracic aortic (TA) rings from coarctation hypertensive rats (CHR) were studied and compared to their sham-operated normotensive control rats (SNR). The effects of these agents were also evaluated in TA or BA with and without endothelium from naive normotensive rats (NNR). Blood pressure (BP) and plasma renin activity (PRA) of CHR were significantly higher than their time-matched SNR.

Relaxant actions of viprostol and prostaglandin E2 on tracheal muscle and their effects on calcium influx.

The relaxant effect of viprostol was studied in monkey and guinea-pig tracheal muscle rings in vitro and compared to that of prostaglandin E2 (PGE2), isoproterenol (ISO) and verapamil (guinea-pig trachea only). Viprostol, PGE2, ISO and verapamil produced a concentration-dependent relaxation of carbachol-contracted tracheal preparations. The rank order of potency in monkey trachea was viprostol = ISO greater than PGE2, while in guinea-pig treachea it was ISO greater than viprostol greater than PGE2 greater than verapamil.

Studies on the effects of viprostol in isolated small blood vessels and thoracic aorta of the rat.

1. The effects of viprostol, prostaglandin E2 (PGE2) and nitroglycerin were studied in basilar artery, small mesenteric artery and the vein parallel to it as well as thoracic aorta of the rat. 2.

The antagonist and partial beta agonist properties of celiprolol in isolated rat cardiac tissue.

Celiprolol was evaluated for its antagonist and partial beta agonist effects in rat spontaneously beating right atria and in electrically stimulated left ventricular strips. Celiprolol, like propranolol, produced a parallel concentration-related rightward shift of the isoproterenol (ISO) (beta agonist) concentration-response curve without decreasing the maximum response in rat right atria. The pA2 values for celiprolol and propranolol were 7.