Calcium-dependent inactivation of the calcium current activated upon hyperpolarization of Paramecium tetraurelia.
نویسندگان
چکیده
منابع مشابه
Calcium-dependent inactivation of the calcium current activated upon hyperpolarization of Paramecium tetraurelia
The Ca2+ current activated upon hyperpolarization of Paramecium tetraurelia decays over a period of 150-200 ms during sustained steps under voltage clamp. At membrane potentials between -70 and approximately -100 mV, the time course of this inactivation is described by a single exponential function. Steps negative to approximately -100 mV elicit currents that decay biexponentially, however. Thr...
متن کاملCalcium current activated upon hyperpolarization of Paramecium tetraurelia
Hyperpolarization of Paramecium tetraurelia under conditions where K+ currents are suppressed elicits an inward current that activates rapidly toward a peak at 25-80 ms and decays thereafter. This peak current (Ihyp) is not affected by removing Cl ions from the microelectrodes used to clamp membrane potential, or by changing extracellular Cl- concentration, but is lost upon removing extracellul...
متن کاملCalcium-induced inactivation of calcium current causes the inter-burst hyperpolarization of Aplysia bursting neurones.
A triphasic series of tail currents which follow depolarizing voltage-clamp pulses in Aplysia neurones L2-L6 was described in the preceding paper (Kramer & Zucker, 1985). In this paper, we examine the nature of the late outward component of the tail current (phase III) which generates the inter-burst hyperpolarization in unclamped cells. The phase III tail current does not reverse between -30 a...
متن کاملCalcium regulation in the protozoan model, Paramecium tetraurelia.
Early in eukaryotic evolution, the cell has evolved a considerable inventory of proteins engaged in the regulation of intracellular Ca(2+) concentrations, not only to avoid toxic effects but beyond that to exploit the signaling capacity of Ca(2+) by small changes in local concentration. Among protozoa, the ciliate Paramecium may now be one of the best analyzed models. Ciliary activity and exo-/...
متن کاملRapid inactivation of depletion-activated calcium current (ICRAC) due to local calcium feedback
Rapid inactivation of Ca2+ release-activated Ca2+ (CRAC) channels was studied in Jurkat leukemic T lymphocytes using whole-cell patch clamp recording and [Ca2+]i measurement techniques. In the presence of 22 mM extracellular Ca2+, the Ca2+ current declined with a biexponential time course (time constants of 8-30 ms and 50-150 ms) during hyperpolarizing pulses to potentials more negative than -4...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of General Physiology
سال: 1992
ISSN: 0022-1295,1540-7748
DOI: 10.1085/jgp.100.2.253