Abstract
Phasic myometrial contractions utilize mechanisms involving the cycling of calcium into and out of intracellular calcium stores. These studies were performed to determine the effects of 2,5-di(tert-butyl)-1,4-hydroquinone (tBHQ), an endoplasmic reticulum Ca(2+)-ATPase inhibitor, on in vitro isometric myometrial contractions. These studies demonstrated that low concentrations of tBHQ (eg. 10 microM) appear to inhibit intracellular calcium cycling, whereas higher concentrations also inhibit extracellular calcium influx. These combined tBHQ effects markedly suppressed myometrial contractions stimulated in response to various agonists including oxytocin, PGF2 alpha, KCl, ionomycin, and Bay K 8644.
Publication types
-
Research Support, U.S. Gov't, P.H.S.
MeSH terms
-
3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / pharmacology
-
Animals
-
Calcium / metabolism
-
Calcium-Transporting ATPases / antagonists & inhibitors*
-
Dinoprost / pharmacology
-
Dose-Response Relationship, Drug
-
Endoplasmic Reticulum / enzymology*
-
Female
-
Hydroquinones / administration & dosage
-
Hydroquinones / pharmacology*
-
Ionomycin / pharmacology
-
Myometrium / drug effects
-
Myometrium / physiology
-
Oxytocin / pharmacology
-
Potassium Chloride / pharmacology
-
Rats
-
Rats, Sprague-Dawley
-
Uterine Contraction / drug effects*
Substances
-
Hydroquinones
-
Oxytocin
-
Ionomycin
-
Potassium Chloride
-
3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester
-
Dinoprost
-
2-tert-butylhydroquinone
-
Calcium-Transporting ATPases
-
Calcium