caa a22 4500 606163107 CHVBK 20210128100642.0 cr unu---uuuuu 210128e20150401xx s 000 0 eng 10.1007/s11062-015-9505-2 doi (NATIONALLICENCE)springer-10.1007/s11062-015-9505-2 Effects of Agonists of μ-Opioid Receptors on P-Type Calcium Channels in Rat Purkinje Neurons [Elektronische Daten] [O. Egorova, O. Fisyunov, O. Kryshtal] Calcium channels of the P-type play an important role in synaptic transmission in the CNS of mammals; the major part of calcium ions entering the presynaptic terminal comes precisely via these channels. Using the whole-cell patch-clamp technique, we studied the effects of μ-opioids on P-type calcium channels in freshly isolated Purkinje neurons of the rat cerebellum. A selective agonist of μ-opioid receptors, DAMGO (10 nM), caused stable moderate (10 ± 1%, on average) but significant (Р < 0.001; n = 27) potentiation of P-type current in most units. This effect of DAMGO was rather appreciable already at a concentration of 1 nM and reached saturation at 100 nM. The effect developed rapidly (in about 10 sec); it was voltage-dependent and completely reversible. An endogenous selective agonist of μ-opioid receptors, endorphin-1, evoked nearly the same effect (increment 8 ± 1%, n = 6, P < 0.01). DAMGO-caused increase in the amplitude of P-type currents was completely removed after application of an antagonist of opioid receptors, naloxone (100 nM). These data indicate that agonists of μ-opioid receptors, even in nanomolar concentrations, can evoke appreciable potentiation of P-type calcium current mediated by interaction with opioid receptors of the corresponding type. Springer Science+Business Media New York, 2015 μ-opioid receptors nationallicence potentiation nationallicence P-type calcium channels nationallicence Purkinje neurons nationallicence Egorova O. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut Fisyunov O. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut Kryshtal O. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut Neurophysiology Springer US; http://www.springer-ny.com 47/2(2015-04-01), 102-107 0090-2977 47:2<102 2015 47 11062 https://doi.org/10.1007/s11062-015-9505-2 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11062-015-9505-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Egorova O. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut NATIONALLICENCE 700 1- Fisyunov O. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut NATIONALLICENCE 700 1- Kryshtal O. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut NATIONALLICENCE 773 0- Neurophysiology Springer US; http://www.springer-ny.com 47/2(2015-04-01), 102-107 0090-2977 47:2<102 2015 47 11062