Effects of magnesium on isolated rabbit atria
Hammad, D.; Omar, S.A.; Varma, S.
Indian Journal of Physiology and Pharmacology 25(2): 123-130
1981
ISSN/ISBN: 0019-5499 PMID: 7287134 Document Number: 177845
The cardiac effects of magnesium were studied on 40 spontaneously beating rabbit atria at 37 degrees C. Magnesium administered in doses of 30, 60, 120 and 240 mmol elicited dose dependent negative inotropic and chronotropic responses. Larger doses above 240 mmol caused complete atrial arrest. Further it was observed that propranolol with magnesium became more effective in blocking the positive chronotropic and inotropic responses to isoprenaline. The finding is interesting and suggestive that magnesium could be employed either alone or in combination with propranolol in treatment of arrhythmias which are non-responsive to propranolol.