title: Effect of thyrotropin releasing hormone on the accumulation of cAMP by parietal ganglia of a gastropod.
abstract: 1. We had previously shown that thyrotropin releasing hormone (TRH) can stimulate the in vitro accumulation of cAMP by the parietal ganglia of the pond snail Lymnaea emarginata (Grimm-Jørgensen, 1980). 2. The mechanism by which TRH affects cAMP metabolism in parietal ganglia was further studied. 3. The TRH-induced accumulation of cAMP is preceded by a lag period and is of long duration. 4. TRH does not stimulate basal or guanylylimidodiphosphate-stimulated adenylate cyclase activity and is unable to cause an increase in cAMP accumulation when the incubation is carried out in the presence of a phosphodiesterase inhibitor. 5. This finding is compatible with the hypothesis that TRH may cause an increase in cAMP accumulation by means of decreasing phosphodiesterase activity. 6. When the ganglia were incubated with 3H-TRH and the localization of the labeled TRH examined by autoradiographic techniques, reduced silver grains were present only over glial and connective tissue elements. 7. The observed effect of TRH on the cAMP metabolism in parietal ganglia may be due to its action on non-neuronal cells.
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000378:metabolism; D000242:Cyclic AMP / Q000378:metabolism*; D005724:Ganglia / Q000187:drug effects / Q000378:metabolism; D008195:Lymnaea / Q000378:metabolism*; D013806:Theophylline / Q000494:pharmacology; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology*
chemical_list: D013973:Thyrotropin-Releasing Hormone; D013806:Theophylline; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D015056:1-Methyl-3-isobutylxanthine