Effects of ACTH on the synthesis and metabolism of prostaglandin in rat kidney.
Prostaglandin (PG) synthetase activity of rat kidney medulla microsomal fraction was determined in vitro using I-14C-arachidonic acid as substrate. Natural ACTH resulted in a dose dependent suppression of PGE2 formation in vitro. The biosynthesis of PGE2 alpha was enhanced in the presence of ACTH (cortrophin). ACTH4--10 (1-Phe7 or d-Phe7) resulted in decreased PGE2 synthesis. The ratio of PGF2 alpha/PGE2 increased in proportion to the concentration of natural ACTH. The increase in the ratio of PG-s was more pronounced when ACTH4--10 fragments were applied. Natural ACTH in a dose dependent manner inhibited the prostaglandin dehydrogenase activity of kidney cytosol fraction in vitro. Prostaglandin inactivation was suppressed only by high doses of ACTH4--10 (d-Phe7). The data indicate that the natural ACTH and ACTH4--10 fragments might have a physiological role in the regulation of the prostaglandin system of a non-steroidogenic tissue.
D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000818:Animals; D005260:Female; D006911:Hydroxyprostaglandin Dehydrogenases / Q000378:metabolism; D066298:In Vitro Techniques; D007668:Kidney / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D010446:Peptide Fragments / Q000494:pharmacology; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D011453:Prostaglandins / Q000378:metabolism*; D011457:Prostaglandins D / Q000378:metabolism; D011458:Prostaglandins E / Q000378:metabolism; D011460:Prostaglandins F / Q000378:metabolism; D051381:Rats
D010446:Peptide Fragments; D011453:Prostaglandins; D011457:Prostaglandins D; D011458:Prostaglandins E; D011460:Prostaglandins F; D000324:Adrenocorticotropic Hormone; D006911:Hydroxyprostaglandin Dehydrogenases; D011451:Prostaglandin-Endoperoxide Synthases; C011394:ACTH (4-10)