Fig. 9

Acute application of berberine directly suppressed the hyperglycemia-induced Ca²⁺ releases from RyRs in cerebral VSMCs isolated from normal control rats. Typical transient increases of intracellular Ca²⁺ evoked by 10 mM caffeine were recorded when cerebral VSMCs exposed to the 20 mM d-glucose or the combination of 10 μM berberine and 20 mM d-glucose, respectively. At last, the cerebral VSMCs were washed with 20 mM d-glucose (a). Summarized data indicated the average changes of the resting intracellular Ca²⁺ and Ca²⁺ releases from RyRs before and after application of the 20 mM d-glucose and the combination of 10 μM berberine and 20 mM d-glucose, respectively (b). Values are mean ± SEM with the number of cells recorded in parentheses. *P < 0.05 vs. control condition and ^# P < 0.05 vs. high glucose condition