[Effect of sodium oxybutyrate on the development of uterine hyperactivity]

Chronic experiments on ovariectomized rabbits were made to study the effect of sodium hydroxybutyrate, a gamma-hydroxybutyric acid derivative, on the myometrium. The mechanical distension of the uterine horn provoked hyperactivity. The dopamine agonist levodopa dramatically potentiated the mechanical hyperactivity of the rabbit uterus. Sodium hydroxybutyrate (800 mg/kg i.v.) significantly inhibited the mechanical and levodopa uterine hyperactivity. The most powerful inhibitory action was produced on the levodopa hyperactivity. Sodium hydroxybutyrate can be regarded as a potential gravidoprotector. It may be assumed that the dopaminergic system is involved in the development of the myometrium hyperactivity. The GABA-ergic mechanisms are likely to play a definite role in the reduction of uterine contractility.