Endothelin stimulation of rat uterine segment contractility is estrogen-dependent.
To determine whether the effect of endothelin upon in vitro uterine contractility requires estrogen, immature female Long Evans rats were subcutaneously injected daily for 3 days with either estradiol benzoate or vehicle. The uterine contractile response to endothelin (5 or 100 nM) was measured. A response to endothelin in vehicle-treated animals exposed to physiologic (5.6 mM) or high (70.6 mM) potassium levels was also noted. Vehicle-treated uteri did not respond to endothelin; the contractions in estrogen-treated uteri increased by 288%. With high potassium, and without estrogen, no response to endothelin was seen. These data indicate that the contractile effect of endothelin on the uterus requires estrogen.
Department of Obstetrics and Gynecology, New Jersey Medical School, Newark 07103, USA.
L N
LN
Gittens
A
A
Wojtczuk
G
G
Weiss
L T
LT
Goldsmith
D000818:Animals; D019540:Area Under Curve; D016232:Endothelins / Q000494:pharmacology* / Q000502:physiology; D004958:Estradiol / Q000031:analogs & derivatives / Q000494:pharmacology; D004967:Estrogens / Q000502:physiology*; D005260:Female; D011188:Potassium / Q000502:physiology; D051381:Rats; D014590:Uterine Contraction / Q000187:drug effects*
D016232:Endothelins; D004967:Estrogens; C074283:estradiol 3-benzoate; D004958:Estradiol; D011188:Potassium