European Journal of Biomedical and Pharmaceutical Sciences

STRUCTURAL AND FUNCTIONAL ABERRATIONS IN MICE VENTRICULAR TISSUE AFTER ACUTE ADMINISTRATION OF BETA ADRENERGIC AGONIST CLENBUTEROL

Manju Kaundal* and Sushma Sharma

ABSTRACT

Clenbuterol is famous for having protein anabolic and lipolytic actions but recently it has been related to malfunctioning of heart. The present study was designed to investigate the deleterious effects of an acute dose (20 mg/kg body weight) of -agonist clenbuterol on mice ventricular tissue. This was achieved by performing histology, lactate dehydrogenase enzyme assays and electron microscopy. The studies were carried out after 4, 8, 20 and 48 hours after drug administration to mice. The enzyme lactate dehydrogenase exists in five isozymic forms. LDH1 and LDH2, are the maker isoenzymes for studying cardiac injury as their serum analysis provides evidence of suspected tissue damage. From microscopic observations it was deduced that the fiber degeneration, nuclear pycnosis, mitochondrial edema and cristal disruption, were the key deviations in the cardiac muscle post drug administration. Ventricular lactate dehydrogenase enzyme demonstrated escalation in its levels after 4, 8 and 20 hours and a reduction was witnessed only at 48 hour stage. Heart specific isoform LDH1 and LDH2 also displayed a similar pattern. It was assumed that besides structural deviations, a single acute dose of 20 mg/kg body weight of clenbuterol caused alterations in the energy requirements in the ventricular tissue in mice. This was supported by extensive rise in the LDH levels at initial stages of the experiment and when the myocytes were not capable to bear the drug induced stress they got disintegrated resulting in release of the LDH in to serum.

Keywords: Clenbuterol, lactate dehydrogenase, heart, serum, isozymes.