Summary
The positive inotropic effect of (−)-phenylephrine, in the presence of propranolol, was studied after inhibition of neuronal and extraneuronal uptake in isolated papillary muscles from reserpine-pretreated cats. An inhibition of extraneuronal uptake with hydrocortisone influenced the effect of (−)-phenylephrine neither when present alone nor in the presence of cocaine (additional inhibition of neuronal uptake). An inhibition of neuronal uptake with cocaine caused a small but significant increase in the potency of (−)-phenylephrine. We conclude that in cat ventricular cardiac muscle the extraneuronal compartment is apparently neither a “site of loss” nor a “site of gain” for (−)-phenylephrine with respect to force of contraction.
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References
Benfey BG (1980) Cardiac alpha-adrenoceptors. Can J Physiol Pharmacol 58:1145–1157
Brückner R, Hackbarth I, Meinertz T, Schmelzle B, Scholz H (1978) The positive inotropic effect of phenylephrine in the presence of propranolol. Increase in time to peak force and in relaxation time without increase in c-AMP. Naunyn-Schmiedeberg's Arch Pharmacol 303:205–211
Brückner R, Meyer W, Mügge A, Schmitz W, Scholz H (1984) Alpha-adrenoceptor-mediated positive inotropic effect of phenylephrine in isolated human ventricular myocardium. Eur J Pharmacol 99:345–347
Corr PB, Shayman JA, Kramer JB, Kipnis RJ (1981) Increased alpha-adrenergic receptors in ischemic cat myocardium. J Clin Invest 67:1232–1236
Ebner F (1981) The positive inotropic effect of (−)-noradrenaline and (±)-isoprenaline after chemical sympathectomy: Evidence in favour of differences at a postsynaptic site. Naunyn-Schmiedeberg's Arch Pharmacol 316:8–18
Ebner F (1982) Putatively intracellular adrenoceptors contribute to the positive inotropic effect of noradrenaline. Trends Pharmacol Sci 3:195–197
Graefe KH (1981) The disposition of 3H-(−)-noradrenaline in the perfused cat and rabbit heart. Naunyn-Schmiedeberg's Arch Pharmacol 318:71–82
Grohmann M, Trendelenburg U (1984) The substrate specifity of uptake2 in the rat heart. Naunyn-Schmiedeberg's Arch Pharmacol (in press)
Kaumann AJ (1970) Adrenergic receptors in heart muscle: Relations among factors influencing the sensitivity of the cat papillary muscle to catecholamines. J Pharmacol Exp Ther 173:383–398
Kaumann AJ (1972) Potentiation of the effects of isoprenaline and noradrenaline by hydrocortisone in cat heart muscle. Naunyn-Schmiedeberg's Arch Pharmacol 273:134–153
Meinertz T, Nawrath H, Scholz H (1976) Possible role of cyclic AMP in the relaxation process of mammalian heart: Effects of dibutyryl cyclic AMP and theophylline on potassium contractures in cat papillary muscles. Naunyn-Schmiedeberg's Arch Pharmacol 293:129–137
Rawlow A, Fleig H, Kurahashi K, Trendelenburg U (1980) The neuronal and extraneuronal uptake and deamination of 3H-(−)-phenylephrine in the perfused rat heart. Naunyn-Schmiedeberg's Arch Pharmacol 314:237–247
Scholz H (1980) Effects of beta- and alpha-adrenoceptor activators and adrenergic transmitter releasing agents on the mechanical activity of the heart. In: Szekeres L (ed) Handbook of experimental pharmacology, vol 54/I. Springer, Berlin Heidelberg New York, pp 651–733
Schümann HJ (1980) Are there alpha-adrenoceptors in the mammalian heart? Trends Pharmacol Sci 1:195–197
Shibata S, Seriguchi DG, Iwadara S, Ishida Y, Shibata T (1980) The regional and species differences on the activation of myocardial alpha-adrenoceptors by phenylephrine and methoxamine. Gen Pharmacol 11:173–180
Trendelenburg U (1971) Supersensitivity of the isolated nictitating membrane of the cat to sympathomimetic amines after impairment of the intraneuronal mechanisms of inactivation. Naunyn-Schmiedeberg's Arch Pharmacol 271:29–58
Trendelenburg U (1972) Factors influencing the concentration of catecholamines at the receptor. In: Blaschko H, Muscholl E (eds) Handbook of experimental pharmacology, vol 33. Springer Berlin, Heidelberg, New York, pp 726–761
Trendelenburg U, Draskóczy PR, Pluchino S (1969) The density of adrenergic innervation of the cat's nictitating membrane as a factor influencing the sensitivity of the isolated preparation to l-norepinephrine. J Pharmacol Exp Ther 166:14–25
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Mügge, A., Reupcke, C., Schmitz, W. et al. Effects of (−)-Phenylephrine on force of contraction in the presence of cocaine and hydrocortisone in cat papillary muscle. Naunyn-Schmiedeberg's Arch. Pharmacol. 328, 90–93 (1984). https://doi.org/10.1007/BF00496113
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DOI: https://doi.org/10.1007/BF00496113