[Withdrawal symptoms of ethanol are ameliorated by thymopentin in mice].

Objective: To explore the effect of thymopentin (TP5) on the choice of ethanol and ameliorating withdrawal symptoms (anxiety) of ethanol in mice.

Methods: Mice were administered ethanol (v/v) in schedular fashion: 5% (1 week), 10% (1 week) and 15% (4 weeks), followed with the free choice between ethanol and water. Ethanol/(ethanol+water)x100% [E/(E+W)x100%] was measured as an index of ethanol selection. Light-dark box test and elevated plus maze test were chosen for the assessment of anxiety pre-drug and post-drug. After TP5 [0.2 mg/(kgxd), 0.4 mg/(kgxd)], i.p. or saline (vehicle control), i.p. for 14 days, the procedure was repeated.

Result: (1) E/(E+W)x100%: the post-drug values of TP5 (0.2 mg/kg, 0.4 mg/kg) were lower significantly than the pre-drug values. (2) Light-dark box test: the post-drug values of number of entries and time spent in the light chamber of TP5 (0.2 mg/kg, 0.4 mg/kg) were more than the pre-drug values themselves and the post-drug value of saline. (3) Elevated plus maze test: the post-drug values of time spent on open arms of TP5 (0.2 mg/kg, 0.4 mg/kg) were more than the pre-drug values themselves and the post-drug value of salineìand the post-drug values of time spent on close arms of TP5 were less than the pre-drug values.

Conclusion: TP5 could decrease the uptake of ethanol and ameliorate anxious behavior associated with ethanol withdrawal in mice.