Journal article
VERAPAMIL - A SELECTIVE ANTAGONIST OF CONSTRICTOR SUBSTANCES IN DOG CORONARY-ARTERY - IMPLICATIONS FOR VARIANT ANGINA
JA ANGUS, RM BRAZENOR, MA LEDUC
CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY | BLACKWELL SCIENCE | Published : 1982
Abstract
1. Canine circumflex coronary artery ring segments were contracted in vitro by ergometrine, serotonin, phenylephrine, noradrenaline (with propranolol) and a thromboxane A2 analogue, U46619. 2. Ergometrine was classified as a serotonin agonist since concentration-response curves were competitively inhibited by methysergide but not by alpha-adrenoceptor antagonists. 3. Glyceryl trinitrate (IC50 18.6 nmol/l) relaxed the coronary rings precontracted with serotonin, phenylephrine or U46619. In contrast (+/-)-verapamil (0.1-10 mumol/l) was more effective against serotonin than phenylephrine or noradrenaline and was almost inactive against U46619. 4. In a blood perfused left anterior descending cor..
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