Objective      To explore the hypoglycemic effect and mechanism of NNC 55-0396 on db/db mice.       Methods      Twelve wild-type non-diabetic mice and 12 db/db mice were respectively separated into 4 groups by the stochastic indicator method including a wild-type control therapy group

a wild-type NNC group

a db/db control group and a db/db NNC group (6 mice per group). The mice of both NNC groups were given intraperitoneal injection of NNC 55-0396 at a dose of 30 mg/(kg·d) for 7 d

while those of both control groups were given intraperitoneal injec

tion of saline in an identical manner. Changes of  plasma glucose

body weight

basal insulin and total cholesterol were compared after drug administration. Protein expression levels of T-type calcium channel subunits Cav3.1 and Cav3.2 were also eamined by immunohistochemistry and Western blotting.       Results      (1) Compared with the db/db control mice

the level of fasting blood glucose of diabetic db/db mice was significantly lowered (

P

0.01) after NNC 55-0396 treatment. No statistical difference was observed between the two wild type groups. (2) Compared with the db/db control mice

body weight and the levels of insulin and cholesterol of diabetic db/db mice were significantly lowered (

P

0.05) after NNC 55-0396 treatment. (3) NNC 55-0396 significantly decreased the protein expression of Cav3.1 and Cav3.2 in the liver and brain of db/db mice.       Conclusion      NNC 55-0396 lowers blood glucose by adjusting the level of Ca

2+

in vivo

providing a new mechanism for the treatment of diabetes.