Endothelium-dependent effect of bradykinin and ATP on rabbit ventricular myocytes

• Published in: Life sciences (1973) Vol. 64; no. 24; pp. PL291 - PL296
• Main Authors: Ou, Y.J., Shan, Q.X., Bourreau, J-P.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 1999
• Subjects: Adenosine Triphosphate - pharmacology; Animals; ATP; bradykinin; Bradykinin - pharmacology; Calcium - metabolism; cardiac myocytes; Cells, Cultured; Electric Stimulation; endothelial cells; Endothelium, Vascular - cytology; Endothelium, Vascular - drug effects; Endothelium, Vascular - metabolism; fura-2; Heart Ventricles - cytology; Heart Ventricles - drug effects; Heart Ventricles - metabolism; In Vitro Techniques; Ion Transport - drug effects; Myocardial Contraction - drug effects; Myocardium - cytology; Myocardium - metabolism; Rabbits; bradykinin; cardiac myocytes; endothelial cells; ATP; fura-2
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/S0024-3205(99)00182-4

We have investigated the effects of bradykinin (BK) and ATP on Ca 2+ transient induced by electrical-field stimulation in freshly isolated rabbit ventricular myocytes, in the presence or absence of rabbit aortic endothelial cells. BK and ATP induced an increase in intracellular Ca 2+ concentration ([Ca 2+] i) in the endothelial cells, but had no significant effect on Ca 2+ transient in electrical-field stimulated ventricular myocytes. In the presence of cultured endothelial cells, the amplitude of Ca 2+ transient induced by electrical stimulation in ventricular myocytes was decreased. BK and ATP further reduced the amplitude of Ca 2+ transient induced by electrical stimulation in ventricular myocytes. These data show that BK and ATP have endothelium-dependent depressing effects on ventricular myocytes and indicate that substances released from endothelial cells in response to BK and ATP stimulation can modulate ventricular myocytes excitation-contraction coupling. However, identification of the cardioactive mediators produced by the endothelial cells requires further study.