Zhuravl'ova S. Characteristics of low-voltage activated Ca2+ channels of rat thalamic neurons

The dissertation is devoted to investigation of characteristics of two types low-voltage activated Са2+ channels in the enzymatically isolated thalamic neurons of the associative laterodorsal (LD) thalamic nucleus. Voltage-dependence, kinetics of inactivation, pharmacology and selectivity of the LVA current in the thalamic neurons from the animals older than 14 postnatal days were consistent with the existence of two, "fast" and "slow", subtypes of LVA Ca2+ channels. "Fast" Ca2+ channels were sensitive to nifedipine (Kd = 7.1 mM), flunarisine (0.89 mM) and La3+ (0.3 mM) whereas "slow" Ca2+ channels were sensitive to Ni2+ (10 mM) and amiloride (21 mM). Selectivity of the "fast" Ca2+ channels was similar to that found for LVA Ca2+ channels in other preparations, ICa : ISr :IBa = 1.0 : 1.23 : 0.94, while selectivity of the "slow" Ca2+ channels more resembled the selectivity of HVA Ca2+ channels, ICa : ISr :IBa = 1.0 : 2.5 : 3.4.