Effect of oestrogens and progesterone alone and in combination on the female rat plasma kininogen concentrations.

ABSTRACT

PIP The effect of estrogens and progesterone alone and in combination on virgin, female rat plasma kininogen levels was studied. Doses of 5 and 10 mcg/kg/day beta-estradiol and 50 and 250 mcg 2,4dimethyl-5,5-diphenyl pent-4-enoic acid sodium salt for 5 days gave a dose response effect. Doses of .5, 2.5, and 5 mg/kg progesterone had no effect on kinin precursor concentration. However, when varying doses of progesterone were used in conjunction with estrogen, a marked increase in kininogen concentrations produced by the estrogens was reduced by, and in proportion to, the dose of progesterone. The effect was more pronounced with the lower doses of estrogen. It appeared that progesterone reduced the increase in kinin precursor produced by the estrogen alone, in proportion to the estrogen/progesterone ration.^ieng