Fig. 2
Comparison of contractile function in response to different dose of berberine (50, 100 and 200 mg/kg/day) at 60 mM KCl (a) and 10−6 M 5-hydroxytryptamine (5-HT, b) in middle cerebral artery isolated from CON, CON + berberine, Diabetic, and diabetic + berberine rats, respectively. Chronic administration of 50 mg/kg/day berberine had no obvious effects on contractile responsiveness to KCl (a) and 5-HT (b) in CON and diabetic rats, respectively. However, chronic administration of 100 mg/kg/day berberine did not change the contractile responsiveness in CON rats, whereas significantly inhibited the augmented contractile responsiveness to KCl (a) and 5-HT (b) in diabetic rats, respectively. In addition, chronic administration of 200 mg/kg/day berberine significantly inhibited the contractile responsiveness to KCl (a) and 5-HT (b) in both CON and diabetic rats, respectively. CON control rats, CON + berberine control rats administrated with different dose of berberine, Diabetic diabetic rats, diabetic + berberine: diabetic rats administrated with different dose of berberine. Values are expressed as mean ± SEM and n = 8 animals in each group. *P < 0.05 vs. CON rats and # P < 0.05 vs. diabetic rats