Upregulation of L-type Ca(v)1 channels in the development of psychological dependence.

Although L-type voltage-dependent Ca2+ 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.