Possible Interaction: Alprostadil and Oxytocin

“In contrast, in diabetic amnion the presence of oxytocin further decreased the release of 6-keto-PGF1alpha and diminished PGE1 generation.”

“It has also … shown that PGE1 decreases the milk-… activity of oxytocin in the rabbit and rat3,4 whilst in the guinea-pig5 the milk-ejection activity of oxytocin is not decreased by PGE1, PGE2, PGE1α or PGF2α, which in this species all possess milk-ejection activity per se.”

“Nonetheless, significant differences could be detected between PGE-2 and oxytocin treatments.”

“Chronic intrauterine treatment with PGE1 or PGE2 also prevented (P ≤ 0.05) oxytocin decreases in luteal unoccupied and occupied LH receptors on Day 8 postestrus.”

“Plasma progesterone concentrations in ewes receiving PGE1 or PGE1 + oxytocin were greater (P ≤ 0.05) than in vehicle controls or in ewes receiving PGE2 or PGE2 + oxytocin and was greater (P ≤ 0.05) in all treatment groups receiving PGE1 or PGE2 than in ewes treated only with oxytocin.”

“Addition of PGE-2 (1 microgram/ml) caused a further significant (P less than 0.05) increase in oxytocin secretion by cultured granulosa cells, whereas PGF-2 alpha, FSH and LH were ineffective when added to culture media.”

“In contrast, the oxytocin-antagonistic effects of PGE1 and PGE2 (2 microgram/kg each) were completely eliminated after alpha-receptor blockade, while the activity of oxytocin was augmented.”

“Halder, Maiweg & Grosvenor (1970) showed that PGE1 could abolish the milk-ejection activity of oxytocin in the rat.”

“injections of prostaglandin E1 (PGE1) did not produce a change in milk-ejection pressure in the lactating rabbit, but could inhibit the milk-ejection response to oxytocin.”