Pb2+ blocks calcium currents of cultured dorsal root ganglion cells. Academic Article uri icon

Overview

abstract

  • The divalent cation lead (Pb2+) blocks sustained and transient voltage sensitive calcium channel currents of cultured rat dorsal root ganglion cells. The IC50 for inhibition of the total peak current evoked by a step depolarization from -80 to 0 mV was 0.6 microM, compared to an IC50 of 2.2 microM for Cd2+. The current activated by a depolarization from -40 to 0 mV was inhibited by 50% by 1.0 microM Pb2+. Low threshold currents activated by a step from -100 to -30 mV were blocked by Pb2+ at higher concentrations (IC50 = 6 microM). The block progressed in the absence of channel activation and showed little voltage dependence. Peak sodium current was reduced by 6.6% at 1 microM Pb2+ while at 20 microM the peak current was reduced by 40% with marked slowing of the time course of activation. The potassium rectifier current was reduced by 4.1% at 1 microM Pb2+. Thus, Pb2+ selectively blocks calcium currents at concentrations in the range of those causing toxicity in man.

publication date

  • August 5, 1991

Research

keywords

  • Calcium Channels
  • Lead
  • omega-Conotoxins

Identity

Scopus Document Identifier

  • 0025923292

Digital Object Identifier (DOI)

  • 10.1016/0304-3940(91)90730-h

PubMed ID

  • 1656334

Additional Document Info

volume

  • 129

issue

  • 1