Influence of naproxen on uterine PGF2 alpha and the antifertility effect of IUDs in rats.
An IUD was implanted into one horn of the uterus in each of our experimental rats. The animals were mated with males of proven fertility about 2 weeks later. At day 1 of gestation (positive mating smear), the animals were treated with oral naproxen at 2 mg/kg per day or 20 mg/kg per day for 10 consecutive days. Control animals received saline. At day 16 the animals were sacrificed and the implantation rates and fetal survival and pregnancy rates were determined. The IUD completely prevented fetal survival and largely reduced implantation rates. Naproxen did not modify these parameters in either the IUD or the non-IUD horn. In a separate set of experiments, the reduction in uterine levels of immunoreactive PGF2 alpha (iPGF) was measured during the implantation period. Naproxen treatment for 5 days with 2 mg/kg per day or 20 mg/kg per day reduced iPGF from 6.71 +/- 0.93 to 2.19 +/- 0.34 and 1.01 +/- 0.18 ng/100 mg tissue, respectively (P less than 0.01). These data show that the suppression of uterine PG synthesis by naproxen does not interfere with the antifertility effects of IUDs in the rat.
Tang
D C
DC
Family Planning Research Institute, Tongji Medical University, Wuhan, People's Republic of China.
Wu
X R
XR
Zhao
B R
BR
Liu
Y Q
YQ
Li
Y
Y
D000818:Animals; D015237:Dinoprost / Q000096:biosynthesis*; D010064:Embryo Implantation / Q000187:drug effects; D005260:Female; D005298:Fertility / Q000187:drug effects*; D007434:Intrauterine Devices; D009288:Naproxen / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D014599:Uterus / Q000187:drug effects* / Q000378:metabolism
D009288:Naproxen; D015237:Dinoprost