title: Effect of cholera toxin and prostaglandins on the rat choroid plexus in vitro.
abstract: The present study was performed to measure the effects of cholera toxin (CT) and prostaglandins (PG) on choroid plexus cyclic AMP accumulation. Choroid plexuses, isolated from Sprague-Dawley rats, were incubated in Krebs-Ringer bicarbonate buffer containing either CT (10 microgram/ml), heat inactivated CT, prostaglandins, or appropriate controls. After a minimum incubation period of 60 min with CT, cyclic AMP accumulation (pmol/mg protein) in treated incubates (58.10 +/- 6.43, n = 6) was 4 times that in controls (14.-5 +/- 1.4, n = 6). This large increase was only seen when theophylline (10 mM) was in the incubation mixture 3--10 min prior to the end of the incubation period. The increase in cyclic AMP accumulation was dose responsive and was irreversible after 5 min of incubation. Of the 5 prostaglandins studied, only PGE2 resulted in an increase in cyclic AMP accumulation. Cyclic AMP levels were 29.64 +/- 2.5 in controls and 57.57 +/- 3.5 in plexus which had been incubated with PGE2 (20 microgram/ml) for 1 min, and this increase was dose responsive.
mesh_terms: D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D002772:Cholera Toxin / Q000494:pharmacology*; D002831:Choroid Plexus / Q000187:drug effects* / Q000201:enzymology; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D011453:Prostaglandins / Q000494:pharmacology*; D011458:Prostaglandins E / Q000494:pharmacology; D051381:Rats; D013806:Theophylline / Q000494:pharmacology; D014238:Trichloroacetic Acid / Q000494:pharmacology
chemical_list: D011453:Prostaglandins; D011458:Prostaglandins E; D014238:Trichloroacetic Acid; D002772:Cholera Toxin; D013806:Theophylline; D000242:Cyclic AMP; D000262:Adenylyl Cyclases