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ISSN 2522-9028 (Print)
ISSN 2522-9036 (Online)
DOI: https://doi.org/10.15407/fz

Fiziologichnyi Zhurnal

is a scientific journal issued by the

Bogomoletz Institute of Physiology
National Academy of Sciences of Ukraine

Editor-in-chief: V.F. Sagach

The journal was founded in 1955 as
1955 – 1977 "Fiziolohichnyi zhurnal" (ISSN 0015 – 3311)
1978 – 1993 "Fiziologicheskii zhurnal" (ISSN 0201 – 8489)
1994 – 2016 "Fiziolohichnyi zhurnal" (ISSN 0201 – 8489)
2017 – "Fiziolohichnyi zhurnal" (ISSN 2522-9028)

Fiziol. Zh. 2000; 46(6): 12-21


Transmembrane ionic currents in smooth musclecells of rat tail artery

V.L. Reznikov, M.F. Shuba

    A.A.Bogomoletz Institute of PhysiologyNational Academy of Science of Ukraine, Kiev


Abstract

Wholl–cell currents in single smooth muscle cells freshly isolated from the rat tail artery have been studied using patch-clamp recordings techniques. Outward current evoked by depolarizing steps from –70mV consisted of the initial fast and subsequent sustained components. The former was inhibited by 10mM nifedipine and Ca2+-free solution application whereas the latter decreased by only 16% under these conditions. Caffeine at 4mM abolished the fast component and only slightly reduced the sustained component. Both component were inhibited by 1mM TEA+. Adding 10mM EGTA to the pipette solution abolished the fast outward current. In the presence of 10mM TEA+ and 4mM 4-AP an inward current was unmasked. These results suggest that the outward current in these cells is carried mainly via delayed rectifier and Ca2+-activated K+-channels. 4-AP inhibited the sustained component and had no effect on the initial fast outward current, thus A-current is apparently absent.

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