Influence of prostaglandins and a prostaglandin H synthase inhibitor on cervical secretion of the guinea-pig.

Abstract

The modulatory effects of several prostaglandins and a prostaglandin H synthase inhibitor (indomethacin) on basal as well as nerve stimulation induced secretion from the cervical glands of the guinea-pig were studied. Hypogastric nerve stimulation resulted in a secretory response of +113%. Indomethacin dose dependently inhibited this secretory response. Prostaglandins E2, F2 alpha and I2 inhibited and 19-OH prostaglandin E1 reduced nerve stimulation induced secretion. Prostaglandin I2 and 19-OH PGE1 markedly enhanced basal secretion, while indomethacin as well as PGE2 and PGF2 alpha did not induce any secretion of cervical glands. However, PGF2 alpha in combination with the alpha-adrenergic blocker phentolamine resulted in an increase in secretion. The inhibitory effect of prostaglandins on cholinergic secretory innervation might be due to stimulation of adrenergic nerves exerting an inhibitory influence on cholinergic secretomotor innervation. It is suggested that PGI2 and 19-OH PGE1 exert postjunctional stimulatory effects on the secretory lining and that a lack of secretory effect of PGF2 alpha at least in part may be due to stimulatory effects on adrenergic neurons, inhibiting cholinergic secretomotor transmission. Thus, in this in vitro study it is shown that metabolites of the arachidonic acid cascade and a prostaglandin H synthase inhibitor can modulate cervical secretion and thus maybe influence fertilization.