Increased marble-burying behavior in ethanol-withdrawal state: Modulation by gonadotropin-releasing hormone agonist

Abstract

A characteristic behavior in alcohol abstinence state indicates the possibility of obsessive–compulsive behavior in alcoholics. Ethanol is known to reduce hypothalamic synthesis, release, and mRNA expression of gonadotropin-releasing hormone (GnRH) that modulates serotonergic, dopaminergic, and glutamatergic systems, which experience adaptive changes on chronic exposure to ethanol. Such changes are also evident in obsessive–compulsive disorder. Therefore, it was proposed to investigate the effect of ethanol-withdrawal on marble-burying behavior in mice, particularly because it simulates some aspects of obsessive–compulsive behavior; further, the influence of GnRH agonist was studied on the same. Ethanol-withdrawal state was induced after its chronic administration, and marble-burying behavior was observed at 0, 6, 24, 48, and 96 h interval. Further, the influence of leuprolide—a GnRH agonist (50–600 μg/kg, s.c.) or fluoxetine (5–30 mg/kg, i.p.) was investigated on ethanol-withdrawal-induced changes in marble-burying behavior. The results indicated that ethanol-withdrawal led to a gradual increase in marble-burying behavior upto 48 h with peak at 24 h interval. Administration of leuprolide (100–600 μg/kg, s.c.), 30 min prior to 24 h interval, dose dependently reduced ethanol-withdrawal-induced increase in marble-burying behavior, and this effect was comparable to that of fluoxetine (15 and 30 mg/kg, i.p.). Further, twice daily administration of leuprolide (50 μg/kg, s.c), concomitant with ethanol, prevented the gradual increase in marble-burying behavior after ethanol-withdrawal and this effect was comparable to fluoxetine (5 mg/kg, i.p.). In conclusion, ethanol-withdrawal on chronic administration increases marble-burying behavior in mice; its development and expression is attenuated by leuprolide.