title: Temperature-dependence of desensitization induced by acetylcholine and histamine in guinea-pig ileal longitudinal muscle.
abstract: 1. The effects of temperature on the time course of desensitization induced by acetylcholine and histamine, and on the recovery from desensitization were studied in the longitudinal muscle of the guinea-pig ileum. 2. Self- and cross-desensitization produced by acetylcholine (10(-5) M) occurred rapidly in the first 10 min of exposure to the agonist, with the same time course and the same degree of desensitization over the temperature range of 11 degrees C to 31 degrees C. 3. Self-desensitization produced by histamine (10(-5) M) also occurred rapidly in the first 10 min of exposure to the agonist, and showed great temperature-dependence, especially at 11 degrees C and 21 degrees C, but scarcely occurred at 6 degrees C. 4. Cross-desensitization produced by histamine developed gradually with time and showed a moderate temperature-dependence between 11 degrees C and 31 degrees C, but scarcely occurred at 6 degrees C. 5. The recovery processes from desensitization showed marked temperature-dependence. Recovery was halted completely at 11 degrees C. 6. These studies suggest that acetylcholine-induced desensitization may be attributed to a single non-specific mechanism. Histamine-induced desensitization may be due to at least two mechanisms: it occurs in both a specific and non-specific manner. Each of these desensitizations can be characterized by its unique temperature-dependence.
authors.affiliation: Department of Chemical Pharmacology, Faculty of Pharmaceutical Sciences, University of Tokushima, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Horio
authors.forename: M
authors.initials: M
authors.lastname: Shima
authors.forename: H
authors.initials: H
authors.lastname: Ueda
authors.forename: Y
authors.initials: Y
authors.lastname: Ishida
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D005260:Female; D006168:Guinea Pigs; D006207:Half-Life; D006632:Histamine / Q000494:pharmacology*; D007082:Ileum / Q000187:drug effects; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D009130:Muscle, Smooth / Q000187:drug effects*; D013696:Temperature
chemical_list: D006632:Histamine; D000109:Acetylcholine