Uteroplacental circulatory disturbance mediated by prostaglandin F-2 alphain rats exposed to microwaves

To clarify the effects of microwaves on pregnancy, uterine or uteroplacenta l blood how and endocrine and biochemical mediators, including corticostero ne, estradiol, prostaglandin E-2 (PGE(2)), and prostaglandin F(2)alpha (PGF (2)alpha), were measured in rats exposed to continuous-wave (CW) microwave at 2 mW/cm(2) incident power density at 2450 MHz for 90 min. Colonic temper ature in virgin and pregnant rats was not significantly altered by microwav e treatment. Microwaves decreased uteroplacental blood flow and increased p rogesterone and PGF(2)alpha in pregnant, but not in virgin rats. Intraperit oneal (i.p.) administration of angiotensin II, a uteroplacental vasodilator , before microwave exposure prevented the reduction in uteroplacental blood how and the increased progesterone and PGF(2)alpha in pregnant rats. Incre ased corticosterone and decreased estradiol during microwave exposure were observed independent of pregnancy and pretreatment with angiotensin II. The se results suggest that microwaves (CW, 2 mW/cm2, 2450 MHz) produce uteropl acental circulatory disturbances and ovarian and placental dysfunction duri ng pregnancy, probably through nonthermal actions. The uteroplacental distu rbances appear to be due to actions of PGF2 alpha and may pose some risk fo r pregnancy. (C) 2000 Elsevier Science Inc. All rights reserved.