Upregulation of L‐type Ca v 1 channels in the development of psychological dependence

Although L‐type voltage‐dependent Ca 2+ channels regulate activity‐dependent processes including synaptic plasticity and synapse formation, there are few data on the changes of Ca v 1 channel expression in psychological dependence. This study investigated the role of L‐type Ca v 1 channel expression in the brain of mouse that was psychologically dependent on methamphetamine (2 mg/kg, subcutaneous injection [s.c.]), cocaine (10 mg/kg, s.c.), and morphine (5 mg/kg, s.c.) with the conditioned place preference paradigm. Intracerebroventricular administration of nifedipine (3, 10, and 30 nmol/mouse) dose‐dependently reduced the development of methamphetamine‐, cocaine‐, and morphine‐induced rewarding effect. Under such conditions, protein levels of both Ca v 1.2 and Ca v 1.3 in the frontal cortex and the limbic forebrain were significantly increased on methamphetamine‐, cocaine‐, and morphine‐induced psychologically dependent mice. These findings suggest that the upregulation of Ca v 1.2 and Ca v 1.3 participated in the development of psychological dependence. Synapse 64:440–444, 2010. © 2010 Wiley‐Liss, Inc.