Is renin a factor in the etiology of essential hypertension?
The widespread clinical study of converting-enzyme inhibitors has shown that they are effective antihypertensive drugs even in patients who may manifest either normal or decreased plasma renin activity. This suggests either that renin in a site other than plasma may play a contributory role in essential hypertension or that the hypotensive effect is caused by increased concentrations of kinins and prostaglandins, both demonstrated consequences of converting-enzyme inhibitor administration. Specific renin inhibitors appropriate for studies in humans would aid in the resolution of this question. Four classes of compounds have been demonstrated to be renin inhibitors of high potency: specific antibody, general peptide inhibitors of acid proteases, analogs of angiotensinogens, and peptides that are related to the amino-terminal sequence of prorenin. With the purification of renin, specific polyclonal or monoclonal antibodies have become available. The former have already been used extensiv
