[Effect of angiotensin and taurine on arrhythmia in cultured neonatal rat hypertrophic heart myocytes].
Angiotensin (Ang) II (1, 10, 100 and 1000 nmol.L-1) was found to increase spontaneous contractile frequency dose-dependently in neonatal rat cardiac myocytes cultured for 3 d. After exposure to Ang II (100 nmol.L-1) for 7 d, neonatal rat heart cells became hypertrophy with increased frequency, elevated APA, prolonged ADP50 and ADP90, and shortened SCL. Addition of ouabian (Oua) 50 nmol.L-1 to the hypertrophic myocytes caused more frequent arrhythmia. Taurine (20 mmol.L-1) was shown to inhibit these changes induced by Ang II. These results suggest that Ang II can increase autorhythmicity as well as sensibility to Oua in cultured cardiac myocytes. These effects might be related to the promotion of Ca2+ influx.
Tao
L
L
Department of Cardiovascular Pharmacology, Nanjing Medical University.
Wang
H X
HX
Rao
M R
MR
D000200:Action Potentials / Q000187:drug effects; D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D000831:Animals, Newborn; D006332:Cardiomegaly / Q000473:pathology*; D002478:Cells, Cultured; D009200:Myocardial Contraction / Q000187:drug effects; D009206:Myocardium / Q000473:pathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013654:Taurine / Q000494:pharmacology*
D000804:Angiotensin II; D013654:Taurine