Two-dimensional electrophoretic analysis of myocardial proteins from lead-exposed rabbits.

Despite reported adverse effects, the cardiovascular toxicity of lead remains controversial. The purpose of the present study was to determine if low-level subchronic exposure of rabbits to lead would produce detectable, concentration-dependent changes in myocardial proteins. Lead was administered to male Dutch Belted rabbits as a lead acetate solution, adjusted weekly to achieve and maintain the target blood lead levels of 0, 20, 40, and 80 microg/dL for 15 weeks. Lead exposures did not affect heart or body weights. Myocardial concentrations of lead at sacrifice were 58+/-25, 69+/-23, 102+/-62, and 105+/-37 ng/g. Of 808 individual proteins resolved by two-dimensional electrophoresis (2-DE) in ventricular homogenates, 162 had coefficients of variation < 20%. A number of proteins were tentatively identified based on coordinate positions homologous to other established 2-DE patterns. Despite variable expression of some protein spots, none of the protein abundances analyzed were found to be significantly altered (P < 0.001) by the lead exposures studied. Therefore results show no detectable effect of a low-body burden of lead on major myocardial proteins of the rabbit.