caa a22 4500 477074286 CHVBK 20180405111435.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF02262770 doi (NATIONALLICENCE)springer-10.1007/BF02262770 Serotonin-induced changes in the activity of single Ca2+ channels in Helix pomatia neurons [Elektronische Daten] [E. Lukyanetz, A. Sotkis] The influence of the neurotransmitter serotonin (5-hydroxytryptamine, 5-HT) on single Ca2+ channel activity was studied on unidentified neurons of the snailHelix pomatia. Only one type of Ca2+ channels with the unitary conductance of 5 pS was identified using 100 mM Ca2+ in the patch pippette under patch-clamp in a cell-attached configuration. The amplitude histogram showed only one peak with the mean value of 0.5 pA at the testing potential of −30 mV. The distribution of channel open times monotonically declined with the mean time constant of 0.2 msec. The distribution of channel closed times could be fitted by a double-exponential curve with time constants of 1 and 12 msec. The study of the effect of 5-HT on Ca2+ single channel activity showed that 5-HT influenced the channel molecule indirectly, as the transmitter could exert its effect by being added to the bath solution, which did not come into contact with the tested membrane fragment under the micropipette tip. 5-HT prolonged the mean channel open time (up to 0.3 msec) and proportionally decreased both channel closed time constants to 0.4 and 6.0 msec, respectively. A conclusion is made that enhancement of Ca2+ macrocurrent by 5-HT is determined by three factors: (i) changes in kinetics of aiready existing channels, (ii) an increase in the number of active channels of the same type, and (iii) an increase in probability of a channel being open. At the same time, the unitary channel conductance was not affected by the transmitter. Plenum Publishing Corporation, 1997 Lukyanetz E. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kiev, Ukraine aut Sotkis A. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kiev, Ukraine aut Neurophysiology Kluwer Academic Publishers-Plenum Publishers 28/2-3(1996-03-01), 103-110 0090-2977 28:2-3<103 1996 28 11062 https://doi.org/10.1007/BF02262770 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02262770 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lukyanetz E. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kiev, Ukraine aut NATIONALLICENCE 700 1- Sotkis A. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kiev, Ukraine aut NATIONALLICENCE 773 0- Neurophysiology Kluwer Academic Publishers-Plenum Publishers 28/2-3(1996-03-01), 103-110 0090-2977 28:2-3<103 1996 28 11062 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer