Calcium-mediated inactivation of calcium current inParamecium
نویسندگان
چکیده
منابع مشابه
Inactivation of calcium channel current in the calf cardiac Purkinje fiber. Evidence for voltage- and calcium-mediated mechanisms
We have studied the influence of divalent cations on Ca channel current in the calf cardiac Purkinje fiber to determine whether this current inactivates by voltage- or Ca-mediated mechanisms, or by a combination of the two. We measured the reversal (or zero current) potential of the current when Ba, Sr, or Ca were the permeant divalent cations and determined that depletion of charge carrier doe...
متن کاملCalcium-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-dependent inactivation of calcium current in synaptic terminals of retinal bipolar neurons.
Giant synaptic terminals (approximately 10 micrometer diameter) of bipolar neurons from goldfish retina were used to directly investigate calcium-dependent inactivation of presynaptic calcium current. During sustained depolarization, calcium current was initially constant for a period lasting up to several hundred milliseconds and then it declined exponentially. The duration of the initial dela...
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 کاملInactivation of N-type calcium current in chick sensory neurons: calcium and voltage dependence
We have studied the inactivation of high-voltage-activated (HVA), omega-conotoxin-sensitive, N-type Ca2+ current in embryonic chick dorsal root ganglion (DRG) neurons. Voltage steps from -80 to 0 mV produced inward Ca2+ currents that inactivated in a biphasic manner and were fit well with the sum of two exponentials (with time constants of approximately 100 ms and > 1 s). As reported previously...
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: The Journal of Physiology
سال: 1980
ISSN: 0022-3751
DOI: 10.1113/jphysiol.1980.sp013391