Effect of Prostaglandins on Oviduct Motility in Estrous Rabbits

• Published in: Biology of reproduction Vol. 9; no. 1; pp. 36 - 45
• Main Authors: Spilman, C H, Harper, M J
• Format: Journal Article
• Language: English
• Published: United States Society for the Study of Reproduction 01-08-1973
• Subjects: Animals; Depression, Chemical; Dose-Response Relationship, Drug; Estrus - drug effects; Fallopian Tubes - drug effects; Female; Injections, Intravenous; Injections, Subcutaneous; Muscle Contraction - drug effects; Pregnancy; Prostaglandin Antagonists; Prostaglandins - administration & dosage; Prostaglandins - pharmacology; Rabbits; Time Factors
• ISSN: 0006-3363; 1529-7268
• DOI: 10.1093/biolreprod/9.1.36

Ballon-tipped fluid-filled catheters were used to study the effects of prostaglandin
(PG) E 1 , E 2 , F 1α , and F 2α on the muscular activity of the oviductal isthmus in unanesthetized unmated New Zealand rabbits. Prostaglandins of the E
series suppressed spontaneous
activity and often completely abolished oviductal muscle activity. PGF 1α and PGF 2α effected
an increase in muscular activity of the oviduct, which was characterized by a maintained
spasmodic contraction. The magnitude of response after the injection of prostaglandins
was often minimal in animals having a low level of spontaneous activity, indicating that
the effect of PGs may be related to other tubal muscle regulatory mechanisms. The
duration of effect of E prostaglandins increased as the dose increased, whereas the length
of the F prostaglandin-induced contraction was the same after the three dose levels
used. The effects of E- and F-series prostaglandins on oviductal muscle activity were
mutually antagonistic; F prostaglandins overcame the suppressive effect of E prostaglandins,
and E prostaglandins abolished the increase in tubal activity caused by F prostaglandins.
These antagonistic effects were dependent on the time interval between the administration
of the prostaglandins. Also, PGE 1 and E 2 abolished spontaneous spasmodic contractions.
The subcutaneous (sc) administration of PGE 1 suppressed spontaneous oviductal activity
for 5.4 h, whereas the suppressive effect of PGE 2 after sc administration lasted only
1.4 h. The effects of similarly administered PGF 1α and F 2α lasted 3.0 and 3.4 h, respectively. In view of their opposite and antagonistic effects on oviductal muscle activity,
the prostaglandins may be involved in the passage of embryos through the oviducts.
The F prostaglandins may act to retain the embryos in the oviduct by virtue of their
occlusive action, and the E prostaglandins may allow the embryos to pass into the uterus
by abolishing tubal occlusion.