caa a22 4500 475836219 CHVBK 20180406123853.0 cr unu---uuuuu 170329e20000701xx s 000 0 eng 10.1023/A:1005208208786 doi (NATIONALLICENCE)springer-10.1023/A:1005208208786 Characteristics of L-Type Ca2+ Channels in the Membrane of Mesenteric Artery Myocytes from Genetically Hypertensive Rats [Elektronische Daten] [M. Harhun, A. Belevich, Ya. Tsytsuyra, I. Filyppov, M. Shuba] Using the standard voltage-clamp technique in the whole-cell mode, we studied the characteristics of barium currents (I Ba; Ba2+ concentration in the external solution was 5 mM) carried through L-type Ca2+ channels in the membrane of myocytes of the resistive mesenteric artery from normotensive and genetically hypertensive rats (NR and GHR, respectively). To perforate the membrane, we used amphotericin B. The arbitrary density of I Ba through the plasma membrane of GHR myocytes significantly exceeded this parameter in the NR group. For both animal groups, activation curves plotted as the dependence of the membrane conductance (G Ba) on the membrane potential were not significantly different: the membrane potential for half activation (V 0.5) of I Ba in the NR myocytes was equal to 1.0 ± 0.3 mV with slope factor k = 6.3 ± 0.4 mV, whereas in the GHR myocytes V 0.5 = -1.6 ± 0.2 mV and k = 6.2 ± 0.5 mV. The stationary inactivation curves for I Ba differed significantly: in the NR myocytes, V 0.5 = -24.2 ± 0.4 mV and k = 8.3 ± 0.2 mV, whereas in the GHR myocytes such parameters were, respectively, -21.4 ± 0.4 and 8.7 ± 0.3 mV. The pattern of intersection of stationary activation and stationary inactivation curves for I Ba was indicative of the existence of a "window current,” i.e., the non-inactivating component of I Ba within the -40 to ±20 mV range; the phenomenon was clearly pronounced in the GHR myocytes. Differences in the arbitrary density of integral I Ba and window current were observed. These differences can cause an increased tone of the blood vessels in hypertensive animals. Plenum Publishing Corporation, 2000 myocyte nationallicence mesenteric artery nationallicence patch clamp nationallicence L-type Ca2+ channels nationallicence hypertension nationallicence Harhun M. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut Belevich A. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut Tsytsuyra Ya Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut Filyppov I. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut Shuba M. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut Neurophysiology Kluwer Academic Publishers-Plenum Publishers 32/4(2000-07-01), 260-265 0090-2977 32:4<260 2000 32 11062 https://doi.org/10.1023/A:1005208208786 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1005208208786 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Harhun M. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut NATIONALLICENCE 700 1- Belevich A. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut NATIONALLICENCE 700 1- Tsytsuyra Ya Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut NATIONALLICENCE 700 1- Filyppov I. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut NATIONALLICENCE 700 1- Shuba M. Bogomolets Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine aut NATIONALLICENCE 773 0- Neurophysiology Kluwer Academic Publishers-Plenum Publishers 32/4(2000-07-01), 260-265 0090-2977 32:4<260 2000 32 11062 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer