Galanin n-terminal fragment (1-15) decreases the voluntary alcohol intake in rats

Abstract

Galanin (GAL) is involved in drug abuse and addiction including alcohol intake. In this work, we have analysed the role of the N-terminal GAL fragment (1-15) [GAL(1-15)] in voluntary ethanol consumption in rats using the two-bottle choice paradigm as well as compare the effects of GAL(1-15) with GAL. The two-bottle choice test was used to determine the voluntary ethanol consumption of rats (Castilla-Ortega et al., 2016). Three sets of experiments were conducted. In the first set of experiments, a dose-response curve of GAL(1-15) was performed. Groups of rats (n=7-9) received i.c.v. GAL(1-15) 1 nmol, 3 nmol or vehicle 2, 14 and 24 hours before the measures. In the second set of experiments, the effects in two-bottle choice test of GAL 3 nmol, and GAL(1-15) 3 nmol were compared. In the last set of experiments rats received i.c.v. GAL(1-15) 3nmol combined with GALR2 antagonist M871 3 nmol 2 hours before the measures. GAL(1-15) 3nmol significantly decreased the alcohol intake 2 (p<0.05), 14 (p<0.05) and 24 (p<0.05) hours after its administration. Moreover, 2 hours after i.c.v. GAL(1-15) 3nmol a significantly decreased by 90% in preference was observed (p<0.05). This effect was maintained 24hours. GAL(1-15) also significantly reduced the alcohol intake (p<0.05) and preference (p<0.05) compared with GAL. GALR2 antagonist M871 significantly blocked the decreased in the ethanol intake (p<0.05) and preference (p<0.05) induced by GAL(1-15) 2 hours after its administration. These results indicates that GAL(1-15) induces a strong reduction in preference and alcohol consumption in rat, showing a differential role than GAL. These results may give basis for the development of novel therapeutic strategies using GAL(1-15) for treatment of alcohol addiction.