caa a22 4500 469078561 CHVBK 20180323132942.0 cr unu---uuuuu 170328e19921101xx s 000 0 eng 10.1007/BF00169008 doi (NATIONALLICENCE)springer-10.1007/BF00169008 KCl-induced insulin secretion from RINm5F cells is mediated through Ca2+ influx along L-type Ca2+ channels [Elektronische Daten] [M. Roenfeldt, H. Safayhi, H.P.T. Ammon] Summary: In order to characterize the voltage-dependent Ca2+ channels of insulin secretory RINm 5F cells, we have studied the binding of the dihydropyridine (DHP) type Ca2+ antagonist PN 200-110 and its effect on insulin release. In the membrane preparation from RINm 5F cells [3H]-(+)-PN 200-110 bound to a high affinity binding site in a stereoselective manner (KD: 7.0 nM, Bmax: 858 fmol/mg protein). The benzothiazepine type Ca2+ antagonist D-cis-diltiazem increased the binding of [3H]-(+)-PN 200-110 in a temperature-dependent manner. The phenylalkylamine-type Ca2+ antagonist verapamil decreased PN binding with an IC50 of 100 μM. (+)-PN 200-110 inhibited KCl-(25 mM)-induced insulin release (IC50 = 10 nM), Effects on binding and hormone release occurred over comparable concentration ranges: 1 μM PN 200-110 produced 100% displacement and totally abolished depolarization-mediated insulin release. The N-type Ca2+-antagonist ω-conotoxin showed no effect on KCl-induced insulin release. The data suggest that in RINm 5 F cells only l-type Ca2+ channels are involved in the mechanism of depolarization-mediated insulin release. Springer-Verlag, 1992 PN 200-110 nationallicence Insulin release nationallicence Calcium channel nationallicence diltiazem nationallicence Rat insulinoma cell nationallicence Roenfeldt M. Department of Pharmacology, Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, W-7400, Tübingen, Federal Republic of Germany aut Safayhi H. Department of Pharmacology, Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, W-7400, Tübingen, Federal Republic of Germany aut Ammon H.P.T. Department of Pharmacology, Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, W-7400, Tübingen, Federal Republic of Germany aut Naunyn-Schmiedeberg's Archives of Pharmacology Springer-Verlag 346/5(1992-11-01), 527-531 0028-1298 346:5<527 1992 346 210 https://doi.org/10.1007/BF00169008 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00169008 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Roenfeldt M. Department of Pharmacology, Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, W-7400, Tübingen, Federal Republic of Germany aut NATIONALLICENCE 700 1- Safayhi H. Department of Pharmacology, Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, W-7400, Tübingen, Federal Republic of Germany aut NATIONALLICENCE 700 1- Ammon H.P.T. Department of Pharmacology, Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, W-7400, Tübingen, Federal Republic of Germany aut NATIONALLICENCE 773 0- Naunyn-Schmiedeberg's Archives of Pharmacology Springer-Verlag 346/5(1992-11-01), 527-531 0028-1298 346:5<527 1992 346 210 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer