A temporal profile of changes in myocardial copper after isoproterenol induced cardiac necrosis.

The changes in myocardial copper were studied over a period of five days after producing myocardial necrosis in albino rats by subcutaneous injection of isoproterenol. Two different doses of isoproterenol (85 mg/kg & 42.5 mg/kg) were used to study the effect of variation in the extent of myocardial damage on the behaviour of myocardial copper. It was interesting to note that there was mainly an increase in myocardial copper with the lower dose of isoproterenol whereas there was mainly a fall in myocardial copper with the higher dose of isoproterenol. It has been hypothesized that this difference in behaviour of myocardial copper with respect to the different doses of isoproterenol is related to the extent of the myocardial tissue which escapes injury. Confirmation of myocardial necrosis was done by ECG, enzymes (SGOT, SGPT & LDH) and histology. Estimation of myocardial copper was done by atomic absorption spectrophotometry (Perkin Elmer 303).