Fig. 8.

Effects of vinpocetine on mitochondrial ATP synthesis (a) and ATPase activity (b). The rate of ATP synthesis in glutamate plus malate (G + M) supported mitochondria (0.5 mg/ml mitochondrial protein was measured in standard medium supplemented with the inhibitor of adenylate kinase, ADP (2 mM) in the presence (hatched bars on (a) and dotted line on the inset) or absence (white bars on (a), solid line on the inset) of vinpocetine. At 200 s G + M initiated oxidative substrate-dependent ATP synthesis. Oligomycin (oligo; 5 μM) inhibited oxidative phosphorylation. ATPase activity (b) was measured on the basis of hydrolysis of exogenous ATP given to mitochondria. ATP hydrolysis was measured under resting conditions (buffer), in the presence of uncoupler FCCP (250 nM) and in the presence of alamethicin, a pore-forming antibiotics. Vinpocetine (vinpo; 30 μM; gray bars). * indicates significant difference (p < 0.05, n > 4) from the corresponding vinpocetine-free controls (white bars)