Multiple conductance levels in rat heart inner mitochondrial membranes studied by patch clamping.
The behavior of the mitochondrial inner membrane multiple conductance channel (MCC) which has a peak conductance of 1-1.5 nS has been examined in rat heart mitochondria. MCC can display several unique characteristics: (a) prolonged open and closed times on the order of seconds to minutes, (b) a voltage dependence in which MCC opens (negative potential) or closes (positive potential) generally in steps, (c) a response to inhibitors such as amiodarone in steps corresponding at least approximately to those in (b), (d) a 'free-running mode' in which the current level rapidly fluctuates between a minimum of nine conductance levels but with a preferred occupation of the 0.5-0.7 nS levels, and (e) very large transitions (1-1.5 nS) resolved at 4 kHz bandwidth as single events with variable mean open time.
Zorov
D B
DB
Department of Biological Sciences, State University of New York, Albany 12222.
Kinnally
K W
KW
Perini
S
S
Tedeschi
H
H
D000818:Animals; D004553:Electric Conductivity; D066298:In Vitro Techniques; D007425:Intracellular Membranes / Q000502:physiology*; D008564:Membrane Potentials; D008929:Mitochondria, Heart / Q000502:physiology* / Q000648:ultrastructure; D051381:Rats; D011919:Rats, Inbred Strains