Actions of the sympathomimetic bronchodilator, rimiterol (R798), on the cardiovascular, respiratory and skeletal muscle systems of the anaesthetized cat
- 1 August 1972
- journal article
- research article
- Published by Wiley in British Journal of Pharmacology
- Vol. 45 (4) , 574-583
- https://doi.org/10.1111/j.1476-5381.1972.tb08115.x
Abstract
1. The actions of rimiterol [erythro(3,4-dihydroxyphenyl, 2-piperidyl methanol hydrobromide)], a new sympathomimetic bronchodilator, have been compared with those of salbutamol and laevoisoprenaline on the heart and lungs, and on contractions of the soleus muscle of cats under chloralose anaesthesia.2. Rimiterol and salbutamol injected intravenously were about equipotent in all tests, and were about 8 times less potent than laevoisoprenaline both in opposing the bronchoconstrictor action of 5-hydroxytryptamine, and in decreasing the tension and degree of fusion of incomplete tetanic contractions of the cat soleus muscle. They were about 19 times less potent than laevoisoprenaline in increasing heart rate.3. The effect on the soleus muscle is considered to be analogous to the muscle tremor that often occurs in man, and the results therefore suggest that systemic administration of bronchodilator doses of rimiterol, like salbutamol, may produce muscle tremor as an unwanted side-effect.4. When equipotent doses to oppose 5-hydroxytryptamine-induced bronchospasm were compared, rimiterol and salbutamol produced less tachycardia than did laevoisoprenaline. In order to match the tachycardia produced by laevoisoprenaline, the doses of rimiterol or salbutamol had to be increased about two and a half times. This safety margin for salbutamol in the cat is considerably less than that reported by others for different species, which suggests that beta(1)- and beta(2)-adrenoceptors may be less clearly differentiated in the cat than they are in other laboratory animals.Keywords
This publication has 18 references indexed in Scilit:
- The comparative pharmacology of WG253 (rimiterol hydrobromide), a new bronchodilator.1971
- Antagonism of acetylcholine-induced bronchospasm by WG 253, a new sympathomimetic amineJournal of Pharmacy and Pharmacology, 1971
- Preliminary Studies of a New Bronchodilator (WG 253) in ManThe Journal of Clinical Pharmacology and New Drugs, 1971
- Comparative Studies of the Protective Effect of Alupent® and Th 1165a Against Histamine in ManRespiration, 1971
- The effect of adrenaline on the contraction of human muscleThe Journal of Physiology, 1970
- Actions of some sympathomimetic bronchodilator and beta‐adrenoceptor blocking drugs on contractions of the cat soleus muscleBritish Journal of Pharmacology, 1970
- Studies on the mode of action of hexobendine, a prospective anti‐anginal drugBritish Journal of Pharmacology, 1969
- Salbutamol: a new, selective β‐adrenoceptive receptor stimulantBritish Journal of Pharmacology, 1969
- The effects of adrenaline, noradrenaline and isoprenaline on skeletal muscle contractions in the catThe Journal of Physiology, 1958
- Mechanics of Respiration in Unanesthetized Guinea PigsAmerican Journal of Physiology-Legacy Content, 1958