Renin 1978

The storage, synthesis, release, measurement, carriage, action and blockade of the hormones of the renin-angiotensin system are considered, with emphasis given to the effects of intrarenal vasodilatation and vasoconstriction on renin release. The concept that variation of calcium flux in the juxtaglomerular cell is the possible final step in renin release is considered. Changing views on the main site of action of angiotensin are examined, particularly in control of the cardiovascular system and of drinking behavior through a site of action in the brain. The role that blockade of various parts of the renin-angiotensin system has played in elucidating the mechanism of action of the system is discussed. The need to consider specificity of blockade in such research is emphasized. Modification of the action of angiotensin by possible initiation of a chemical cascade involving the release of other active substances is discussed. Finally, the major functions of the renin-angiotensin system in the control of blood pressure, of sodium and water balance, and of intrarenal events, are summarized.