Cryoactivation of inactive renin in human plasma.

Cryoactivation of plasma renin.

1. The mechanism of increased renin activity after human plasma had been kept at -5 degrees C for 4 days (cryoactivation) was investigated. 2. The increase in renin activity of human plasma by cryoactivation was closely correlated to the increase obtained by incubation with trypsin (r = 0.88, P less than 0.001, n = 10). 3. An inhibitor of thiol enzyme, N-ethylmaleimide did not inhibit cryoactiv...

Activation and reinactivation of inactive renin in normal human plasma.

Various facets of activation of inactive renin by acidification or cold exposure were investigated in normal human plasma. The acid activation obtained by titration was usually less than that by dialysis method, but varied from 41% to 122% of the latter. The acid phase of acid activation accounted for about 70% of the total activation achieved by the combined effects of the acid and alkaline ph...

Incomplete cryoactivation of human renin: a cause of confusion?

Plasma renin activity in normal human pregnancy and in pregnancy-associated hypertension, with reference to cryoactivation.

1. Because hypertension is the central feature of pre-eclampsia, and because plasma renin activity is known to be elevated in normal pregnancy (with conflicting results published for pre-eclampsia), a prospective study of plasma renin activity was conducted in pregnancy, under conditions of a fixed sodium intake, in 178 initially normotensive volunteer subjects. Thirty of these women developed ...

Inactive Renin of High Molecular Weight (Big Renin) in Normal Human Plasma

Normal plasma contains inactive renin, which becomes active when plasma is dialyzed to pH 3.3 and to pH 7.5, or treated with pepsin or trypsin. Under optimal conditions, each of these procedures activated the same quantity of renin, which was not further increased by repeating or combining two procedures, thus suggesting that the same pool of inactive renin was activated by each procedure. When...