Franz Volhard and his students' tortuous road to renovascular hypertension

Harry Goldblatt's name is irrevocably linked to the phenomenon that renal artery constriction increases blood pressure via renin release, even in the absence of significantly decreased renal function. However, "getting there was more than half the fun." A lively competition look place earlier in this century elucidating the role of the kidney in hypertension, in which Franz Volhard and his disciples played a major role. I have reviewed the extensive German literature of the time, and observed that Franz Volhard and his young associates made major contributions investigating decreases in renal perfusion and resultant increases in blood pressure. Hessel, Hartwich, and Volhard made seminal observations in this regard that even preceded those of Goldblatt. A sojourn into this past history gives a revealing insight into our cumulative-albeit still incomplete-knowledge of the kidney, renin-angiotensin system, and blood pressure regulation. Franz Volhard was a colorful figure whose contributions extended far beyond classifying renal diseases.