caa a22 4500 469078510 CHVBK 20180323132942.0 cr unu---uuuuu 170328e19921101xx s 000 0 eng 10.1007/BF00169006 doi (NATIONALLICENCE)springer-10.1007/BF00169006 Effects of calcitonin gene-related peptide (CGRP) on Ca2+-channel current of isolated smooth muscle cells from rat vas deferens [Elektronische Daten] [Ken Nakazawa, Hiroshi Saito, Norio Matsuki] Summary: Effects of calcitonin gene-related peptide (CGRP), a putative non-adrenergic non-cholinergic neutrotransmitter on the electrical properties of the cell membrane, were investigated in enzymically dispersed smooth muscle cells from rat vas deferens. Under current clamp conditions, CGRP (up to 10−7 M) did not induce significant changes in membrane potentials or input resistance in the resting state. The configurations of action potentials elicited by depolarizing current pulses were also unaffected, except that a prolongation of the duration of the action potentials by a high dose (10−7 M) of CGRP was observed in some of the cells. Under whole cell voltage clamp conditions, the transient and sustained K+ currents, activated by depolarizing voltage-steps, were apparently decreased in the presence of 10−9 to 10−7 M CGRP. The peptide increased the voltage-gated Ca2+ current in cells loaded with 145 mM Cs+ solution in order to block the K+ currents. The voltage-dependency of the peak Ca2+ current was not changed by CGRP. Ba2+ (10.8 mM) was used as a charge carrier for the Ca2+-channel current to clarify further the effects of CGRP on the properties of the current. CGRP (10−8 M) delayed the inactivation time course of the Ca2+-channel current and slowed the recovery from inactivation. The peptide did not affect the steady-state inactivation measured by changing the holding potential. The Ca2+-channel current in the presence of CGRP was suppressed by nicardipine (10−6 M) to the same extent as the current under control conditions. The results suggest that CGRP modifies the L-type Ca2+ channel in smooth muscle cells. Springer-Verlag, 1992 Calcitonin gene-related peptide nationallicence Smooth muscle cells nationallicence Vas deferens - Membrane currents nationallicence Ca2+ channel nationallicence Nakazawa Ken Department of Chemical Pharmacology, Faculty of Pharmaceutical Sciences, The University of Tokyo, 113, Tokyo, Japan aut Saito Hiroshi Department of Chemical Pharmacology, Faculty of Pharmaceutical Sciences, The University of Tokyo, 113, Tokyo, Japan aut Matsuki Norio Department of Chemical Pharmacology, Faculty of Pharmaceutical Sciences, The University of Tokyo, 113, Tokyo, Japan aut Naunyn-Schmiedeberg's Archives of Pharmacology Springer-Verlag 346/5(1992-11-01), 515-522 0028-1298 346:5<515 1992 346 210 https://doi.org/10.1007/BF00169006 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00169006 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Nakazawa Ken Department of Chemical Pharmacology, Faculty of Pharmaceutical Sciences, The University of Tokyo, 113, Tokyo, Japan aut NATIONALLICENCE 700 1- Saito Hiroshi Department of Chemical Pharmacology, Faculty of Pharmaceutical Sciences, The University of Tokyo, 113, Tokyo, Japan aut NATIONALLICENCE 700 1- Matsuki Norio Department of Chemical Pharmacology, Faculty of Pharmaceutical Sciences, The University of Tokyo, 113, Tokyo, Japan aut NATIONALLICENCE 773 0- Naunyn-Schmiedeberg's Archives of Pharmacology Springer-Verlag 346/5(1992-11-01), 515-522 0028-1298 346:5<515 1992 346 210 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer