Current Perspectives Renin Is Not Synthesized by Cardiac and Extrarenal Vascular Tissues A Review of Experimental Evidence

A comprehensive review of physiological and molecular bio-logical evidence refutes claims for synthesis of renin by cardiac and vascular tissues. Cardiovascular tissue renin completely disappears after binephrectomy. Residual putative reninlike activity, where investigated, has had the characteristics of lysosomal acid proteases. Occasional reports of renin or renin mRNA in vascular and cardiac tissues can be ascribed to failure to remove the kidneys 24 hours beforehand, overload-ing of detection systems, problems with stringency in identifi-cation, and illegitimate transcripts after more than 25 cycles of polymerase chain reaction. Others, using more stringent crite-ria, have failed to detect cardiac and vascular renin mRNA. Accordingly, a growing number of investigators have con-cluded that the kidneys are the only source of cardiovascular tissue renin. Although prorenin is secreted from extrarena