Cardiovascular and beta-adrenergic blocking effects of timolol.
The haemodynamic effects of timolol and its inhibiting action on the cardiovascular and bronchial effects of isoproterenol have been studied. Splanchnic nerve activity was recorded. The antiarrhythmic action of timolol was studied on guinea pig isolated atria, using arrhythmias induced by epinephrine, ouabain or coronary ligation in the dog. Timolol is a very potent beta-adrenoceptor blocking agent, without specificity on beta1- or beta2-receptors. No intrinsic beta-stimulating or depressant effects were found. Timolol reduced splanchnic discharges. The antiarrhythmic effect of timolol was limited to epinephrine-induced arrhythmias.
D000319:Adrenergic beta-Antagonists; D000403:Airway Resistance / Q000187:drug effects; D000818:Animals; D001011:Aorta / Q000187:drug effects; D001145:Arrhythmias, Cardiac / Q000139:chemically induced / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects; D001980:Bronchi / Q000187:drug effects; D003326:Coronary Circulation / Q000187:drug effects; D004285:Dogs; D005260:Female; D006168:Guinea Pigs; D006325:Heart Atria / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000037:antagonists & inhibitors; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D011412:Propanolamines / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology; D013153:Splanchnic Nerves / Q000502:physiology; D013830:Thiadiazoles / Q000494:pharmacology*; D013997:Time Factors
D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D013830:Thiadiazoles; D011433:Propranolol; D007545:Isoproterenol