title: Effect of histamine on isolated working guinea pig heart with left ventricular hypertrophy produced by pressure overload.
abstract: Left ventricular hypertrophy in guinea pigs was produced by partial constriction of the ascending aorta. 65-70 d after surgery, the animals were sacrificed and the hearts were mounted on a working heart apparatus. Results showed that all parameters of cardiac function in the hypertrophied (HT) group were depressed. The dose-response (D-R) curves for histamine (H) in the HT group shifted leftward and upward as compared with the sham-operated (S) group. In the presence of pyrilamine (P), the D-R curves for H shifted to the left in the S group, but the curves shifted to the right in the HT group. In the presence of cimetidine (C), the D-R curves for H shifted downward and rightward in both groups. In contrast to H, the D-R curves for norepinephrine (NE) on LVP/HW and CBF/HW in the HT group shifted rightward and downward as compared with the S group. These results indicate that the sensitivity of H2 receptors in hypertrophied heart was increased and that of beta receptors was slightly decreased, suggesting a possible beneficial effect of H2 receptor agonists in the treatment of certain types of cardiac failure, which are insensitive to catecholamine stimulation.
authors.forename: W S
authors.initials: WS
authors.lastname: Luo
authors.forename: Z G
authors.initials: ZG
authors.lastname: Guo
mesh_terms: D000818:Animals; D006332:Cardiomegaly / Q000503:physiopathology*; D002927:Cimetidine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006168:Guinea Pigs; D006334:Heart Function Tests; D006632:Histamine / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D011738:Pyrilamine / Q000494:pharmacology; D011970:Receptors, Histamine H2 / Q000502:physiology
chemical_list: D011970:Receptors, Histamine H2; D002927:Cimetidine; D006632:Histamine; D011738:Pyrilamine; D009638:Norepinephrine