[Inhibitory effect of arachidonic acid on the synthesis of prolactin in human decidual tissues].
Much evidence indicates that human tissues produce prolactin. However, little is known as to which agents regulate its production in decidual tissues. Therefore, it is of interest to examine the effect of arachidonic acid on the production of prolactin, since it is present in considerably large amounts in decidual tissues. The addition of arachidonic acid to culture media resulted in a significant reduction in the amount of prolactin secreted from incubated decidual tissues in a dose-related fashion. Other poly-unsaturated fatty acids, i.e. linoleic and gamma-linolenic acid also inhibited its secretion, whereas saturated fatty acid and mono-unsaturated fatty acids, such as oleic acid, were without effect. The addition of phospholipase A2 and phospholipase C, enzymes to liberate arachidonic acid from phospholipids, also suppressed the secretion of prolactin. Indomethacin and BW-755C, inhibitors of cyclooxygenase and lipoxygenase, respectively, had essentially no effect on the secretion of prolactin. Translatable mRNA for prolactin was detected in decidual tissues. Arachidonic did not alter either the amount of mRNA in prolactin of the amount of its mRNA as a percentage of total mRNA. Thus, it appears that arachidonic acid possibly plays a role as a physiological regulator of prolactin secretion in human decidual tissues. The action of arachidonic acid is not mediated by cyclooxygenase or lipoxygenase products, suggesting that arachidonic acid itself, or its metabolites other than prostaglandin and leukotriene, may be involved in the regulation of prolactin secretion.
Kinoshita
T
T
Department of Obstetrics and Gynecology, Faculty of Medicine, University of Tokyo.
Taketani
Y
Y
Mizuno
M
M
D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism / Q000502:physiology*; D046508:Culture Techniques; D003656:Decidua / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D010741:Phospholipases A / Q000494:pharmacology; D054467:Phospholipases A2; D011247:Pregnancy; D011388:Prolactin / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000378:metabolism
D001095:Arachidonic Acids; D012333:RNA, Messenger; D016718:Arachidonic Acid; D011388:Prolactin; D010741:Phospholipases A; D054467:Phospholipases A2