Striatal G-proteins: effects of unilateral 6-hydroxydopamine lesions

To investigate the molecular mechanisms of denervation-induced dopamine receptor supersensitivity, levels of striatal G-proteins were examined in 6-hydroxydopamine (6-OHDA)-lesioned rats. Increased levels of the alpha-subunits of Gs and G(olf), as measured by immunoblotting, were observed 8 days postlesion and remained elevated up to day 28 (25-45% over the time course). G(i) levels were significantly increased only on day 8 (20%) and G(o) levels remained unaltered. These results suggest that stimulatory G-proteins may be involved in the long-term maintenance of dopamine receptor supersensitivity following denervation.