Repeated cocaine administration increases voltage-sensitive calcium currents in response to membrane depolarization in medial prefrontal cortex pyramidal neurons

NASIF, FERNANDO J.

JOURNAL OF NEUROSCIENCE

SOC NEUROSCIENCE

Año: 2005 vol. 25 p. 3674 - 3674

0270-6474

he medial prefrontal cortex (mPFC) plays a critical role in cocaine addiction. However, evidence to elucidate how the mPFC is functionally involved in cocaine addiction remains incomplete. Recent studies have revealed that repeated cocaine administration induces various neuroadaptations in pyramidal mPFC neurons, including a reduction in voltage-gated K+ currents (VGKCs) and a possible increase in voltage-sensitive Ca2+ currents (ICa). Here, we performed both current-clamp recordings in brain slices and voltage-clamp recordings in freshly dissociated cells to determine whether ICa is altered in mPFC pyramidal neurons after chronic cocaine treatment with a short-term or long-term withdrawal. In addition, a critical role of VGKCs in regulating the generation of Ca2+ plateau potential was also studied in mPFC neurons. Repeated cocaine administration significantly prolonged the duration of evoked Ca2+ plateau potentials and increased the whole-cell ICa in mPFC neurons after a 3 d withdraw