Angiotensin II stimulates PGF(2 alpha)release in cultured neonatal rat ventricular myocytes via L-type calcium channels.
Angiotensin II (Ang II) has been shown to cause Prostaglandin F(2 alpha)(PGF(2 alpha)) release in neonatal rat ventricular myocytes and smooth muscle cells. In these cells, Ang II has also been shown to regulate growth. We used neonatal rat ventricular myocytes to investigate the role of calcium in maintenance of Ang II-induced PGF(2 alpha)release. The amount of PGF(2 alpha)produced was determined by radioimmunoassay. Ang II-induced PGF(2 alpha)release. Pretreatment of neonatal rat ventricular myocytes with different doses (10(-8)M, 10(-7)M, 10(-6)M and 10(-5)M) of diltiazm (voltage-sensitive L-type calcium channel blocker) produced significant inhibition in Ang II-induced PGF(2 alpha)release. Inhibition was first noted at 10(-8)M and was complete at 10(-6)M. Conversely, pretreatment of neonatal rat ventricular myocytes with different doses (10(-8)M, 10(-7)M, 10(-6)M and 10(-5)M) of calcium channel blockers (conotoxin; voltage-sensitive N-type calcium channel blocker or thapsigargin; intracellular calcium channel blocker) produced no changes in Ang II-induced PGF(2 alpha)release. These results strongly suggest that Ang II-induced PGF(2 alpha)release in neonatal rat ventricular myocytes is maintained, at least in part, via increase in extracellular calcium influx.
Oriji
G K
GK
Department of Biology, College of Science and Health, Wayne, NJ 07470, USA. orijig@wpunj.edu
D000804:Angiotensin II / Q000378:metabolism* / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology; D015220:Calcium Channels / Q000378:metabolism; D020746:Calcium Channels, L-Type / Q000378:metabolism*; D002478:Cells, Cultured; D020916:Conotoxins / Q000494:pharmacology; D015237:Dinoprost / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D006352:Heart Ventricles / Q000166:cytology*; D009206:Myocardium / Q000166:cytology*; D011493:Protein Kinase C / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D015398:Signal Transduction; D019284:Thapsigargin / Q000494:pharmacology
D002121:Calcium Channel Blockers; D015220:Calcium Channels; D020746:Calcium Channels, L-Type; D020916:Conotoxins; D000804:Angiotensin II; D019284:Thapsigargin; D015237:Dinoprost; D011493:Protein Kinase C; D002118:Calcium