Eroglu L, Tuna R, Caglayan B
Istanbul University, Istanbul Medical Faculty, Department of Pharmacology and Clinical Pharmacology, Capa, Turkey.
Pharmacol Res. 1996 Feb;33(2):141-4. doi: 10.1006/phrs.1996.0021.
Possible interaction between adenosine and L type Ca2+ channel in the locomotor activity of rats was investigated. R-PIA (0.05 mg kg-1), an adenosine analogue, and caffeine (20 mg kg-1), an adenosine receptor antagonist, significantly decreased and increased locomotor activity, respectively. Ca2+ channel blocker nifedipine (5 mg kg-1) and the channel activator Bay K 8644 (0.5 mg kg-1) did not alter the locomotor activity. However, both drugs significantly potentiated the inhibitory effect of R-PIA on the locomotor activity. Additionally, caffeine induced increase in the locomotor activity was significantly blocked by nifedipine and Bay K 8644. This interaction might be due to the inhibitory effects of nifedipine and Bay K 8644 on the uptake of adenosine by rat brain.
