Interaction between parathyroid hormone and the β-adrenoceptor system in cultured rat myocardial cells

• Published in: Journal of molecular and cellular cardiology Vol. 12; no. 10; pp. 955 - 964
• Main Authors: Larno, Suzanne, Lhoste, François, Auclair, Marie-Claude, Lechat, Paul
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.10.1980
• Subjects: Animals; Animals, Newborn; Calcium; Calcium - pharmacology; Cells, Cultured; Cultivated rat heart cells; Dose-Response Relationship, Drug; Isoprenaline; Isoproterenol - pharmacology; Myocardium - cytology; Myocardium - metabolism; Parathormone; Parathyroid Hormone - pharmacology; Propranolol - pharmacology; Rats; Receptors, Adrenergic - metabolism; Receptors, Adrenergic, beta - metabolism; Sotalol - pharmacology; β-blocking agents; Cultivated rat heart cells; Parathormone; β-blocking agents; Isoprenaline; Calcium
• ISSN: 0022-2828; 1095-8584
• DOI: 10.1016/0022-2828(80)90024-3

The effect of parathyroid hormone (PTH) alone and in combination with dl-sotalol, dl-propranolol, isoprenaline and calcium chloride has been investigated on cultured rat heart cells beating. PTH induced a dose-dependent positive chronotropic effect which was antagonized by sotalol non-competitively. PTH decreased the positive chronotropic effect of isoprenaline by a non-competitive antagonism. PTH reduced the negative chronotropic effect of propranolol by a competitive antagonism and the positive chronotropic effect of calcium chloride by a non-competitive antagonism. Such interactions suggest that PTH may act in vivo not entirely by stimulating a proper receptor.