Article: Lack of evidence for a temperature-mediated change of adrenoceptor type in the rat heart

1. Responses to phenylephrine of left and right atria of the rat heart have been measured at 37 degrees C and 21 degrees C. 2. Differences in basal force of contraction at the two temperatures were attributable solely to differences in frequencies of contraction. 3. Reduction in temperature produced no change in EC50 for phenylephrine nor any greater susceptibility of the responses to blockade by phentolamine rather than propranolol. 4. It is concluded that beta-adrenoceptors of the rat heart are not converted to alpha-adrenoceptors by a reduction in temperature.

Citing Articles

Evidence against the temperature-dependent interconversion of histamine H1- and H2-receptors in the guinea-pig ileum.

Bertaccini G, Zappia L Br J Pharmacol. 1983; 78(1):11-6.

PMID: 6130806 PMC: 2044772. DOI: 10.1111/j.1476-5381.1983.tb09357.x.

alpha 1-adrenoceptor activation can increase heart rate directly or decrease it indirectly through parasympathetic activation.

Flavahan N, McGrath J Br J Pharmacol. 1982; 77(2):319-28.

PMID: 6128039 PMC: 2044592. DOI: 10.1111/j.1476-5381.1982.tb09301.x.

[Alpha-adrenoceptors in the myocardium: incidence and functional significance].

Mugge A Klin Wochenschr. 1985; 63(21):1087-97.

PMID: 3001400 DOI: 10.1007/BF02291089.

Alpha-adrenoceptor-mediated chronotropic response: influence of temperature and basal spontaneous rate.

Camilion de Hurtado M, Gende O Naunyn Schmiedebergs Arch Pharmacol. 1989; 339(3):315-9.

PMID: 2542809 DOI: 10.1007/BF00173585.

Mechanisms contributing to the differential haemodynamic effects of bombesin and cholecystokinin in conscious, Long Evans rats.

Janssen P, Gardiner S, Compton A, Bennett T Br J Pharmacol. 1991; 102(1):123-34.

PMID: 2043918 PMC: 1917871. DOI: 10.1111/j.1476-5381.1991.tb12143.x.

References

1.

Starke K . Alpha sympathomimetic inhibition of adrenergic and cholinergic transmission in the rabbit heart. Naunyn Schmiedebergs Arch Pharmacol. 1972; 274(1):18-45. DOI: 10.1007/BF00501004. View

2.

Daly J, Creveling C, WITKOP B . The chemorelease of norepinephrine from mouse hearts. Structure-activity relationships. I. Sympathomimetic and related amines. J Med Chem. 1966; 9(3):273-80. DOI: 10.1021/jm00321a001. View

3.

Ledda F, Marchetti P, Mugelli A . Studies on the positive inotropic effect of phenylephrine: a comparison with isoprenaline. Br J Pharmacol. 1975; 54(1):83-90. PMC: 1666381. DOI: 10.1111/j.1476-5381.1975.tb07413.x. View

4.

Parr J, Urquilla P . Analysis of the adrenergic receptors of pacemaker and myocardial cells. Eur J Pharmacol. 1972; 17(1):1-7. DOI: 10.1016/0014-2999(72)90261-0. View

5.

Kunos G, Mucci L, Jaeger V . Interconversion of myocardial adrenoceptors: its relationship to adenylate cyclase activation. Life Sci. 1976; 19(10):1597-602. DOI: 10.1016/0024-3205(76)90106-5. View

6.

Wagner J, Reinhardt D . Characterization of the adrenoceptors mediating the positive ino- and chronotropic effect of phenylephrine on isolated atria from guinea pigs and rabbits by means of adrenolytic drugs. Naunyn Schmiedebergs Arch Pharmacol. 1974; 282(3):295-306. DOI: 10.1007/BF00501237. View

7.

Kunos G, Nickerson M . Effects of sympathetic innervation and temperature on the properties of rat heart adrenoceptors. Br J Pharmacol. 1977; 59(4):603-14. PMC: 1667749. DOI: 10.1111/j.1476-5381.1977.tb07728.x. View

8.

Benfey B . Temperature dependence of phenoxybenzamine effects and the adrenoceptor transformation hypothesis. Nature. 1975; 256(5520):745-7. DOI: 10.1038/256745a0. View

9.

Kunos G, Nickerson M . Letter: Temperature, phenoxybenzamine and adrenoceptor transformation. Nature. 1976; 259(5540):251-2. DOI: 10.1038/259251a0. View

10.

Kunos G, Nickerson M . Temperature-induced interconversion of alpha-and beta-adrenoceptors in the frog heart. J Physiol. 1976; 256(1):23-40. PMC: 1309289. DOI: 10.1113/jphysiol.1976.sp011309. View

11.

Kunos G . Thyroid hormone-dependent interconversion of myocardial alpha- and beta-adrenoceptors in the rat. Br J Pharmacol. 1977; 59(1):177-89. PMC: 1667708. DOI: 10.1111/j.1476-5381.1977.tb06992.x. View

Lack of Evidence for a Temperature-mediated Change of Adrenoceptor Type in the Rat Heart