title: Effect of thuringiensin on adenylate cyclase in rat cerebral cortex.
abstract: The purpose of this work is to evaluate the effect of thuringiensin on the adenylate cyclase activity in rat cerebral cortex. The cyclic adenosine 3'5'-monophosphate (cAMP) levels were shown to be dose-dependently elevated 17-450% or 54-377% by thuringiensin at concentrations of 10 microM-100 mM or 0.5-4 mM, due to the activation of basal adenylate cyclase activity of rat cerebral cortical membrane preparation. Thuringiensin also activated basal activity of a commercial adenylate cyclase from Escherichia coli. However, the forskolin-stimulated adenylate cyclase activity in rat cerebral cortex was inhibited by thuringiensin at concentrations of 1-100 microM, thus cAMP production decreased. Furthermore, thuringiensin or adenylate cyclase inhibitor (MDL-12330A) reduced the forskolin (10 microM)-stimulated adenylate cyclase activity at concentrations of 10 microM, 49% or 43% inhibition, respectively. In conclusion, this study demonstrated that thuringiensin could activate basal adenylate cyclase activity and increase cAMP concentrations in rat cerebral cortex or in a commercial adenylate cyclase. Comparing the dose-dependent effects of thuringiensin on the basal and forskolin-stimulated adenylate cyclase activity, thuringiensin can be regarded as a weak activator of adenylate cyclase or an inhibitor of forskolin-stimulated adenylate cyclase.
authors.affiliation: Laboratory of Toxicology and Pharmacology, Department of Veterinary Medicine, National Chung-Hsing University, Taichung, Taiwan, ROC.
authors.forename: San-Fu
authors.initials: SF
authors.lastname: Tsai
authors.forename: Chi
authors.initials: C
authors.lastname: Yang
authors.forename: Shun-Cheng
authors.initials: SC
authors.lastname: Wang
authors.forename: Jiunn-Shiow
authors.initials: JS
authors.lastname: Wang
authors.forename: Jenn-Sheng
authors.initials: JS
authors.lastname: Hwang
authors.forename: Shu-Peng
authors.initials: SP
authors.lastname: Ho
mesh_terms: D000241:Adenosine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology*; D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects* / Q000201:enzymology*; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013400:Sugar Acids / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D013400:Sugar Acids; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; C068295:thuringiensin; D000241:Adenosine