Diurnal differences in toluene induced reward-seeking behavior between melatonin-proficient (C3H) and melatonin-deficient (C57) mice [Melatonin Yeterli (C3H) ve melatonin eksik (C57) farelerde toluen ile oluşan ödül arama davrani{dotless}şi{dotless}nda diurnal farkli{dotless}li{dotless}k]

Objectives: abuse of organic volatile substances (inhalants) has become a social health problem that is increasing in the recent years. toluene as a prototype of inhalants can be use via inhalation,intraperitoneal or intravenous for experimental research on rodents. a conditioning paradigm of toluene inhalation was developed the rewarding effect in mice and rats. aim of this research,investigation of toluene induced reward-seeking behavior at day and night order in melatonin proficient (c3h) and deficient (c57) mice. materials and methods: we were used a shuttle box as divided two compartment for conditioning place preferences. one side of box was white color smooth texture and other side black color. toluene was injected to c3h and c57 for conditioning place preferences test at day and night time points. toluene was injected every two day as 200,400,800 mg/kg and than placed to the white side of shuttle box for 30 min. other days,which was not given toluene,olive oil was injected and than placed to the black side of box for 30 min. totally,injections was 8 pairs. before and after injections conditioning test was applied for 15 min and analyzed from video records. results: in this work,we found reward seeking behavior in 800 mg/kg toluene injected c57 mice at day and night. on the other side,c3h mice were shown 800 mg/kg toluene induced reward seeking behavior at day but not night. reward seeking behavior did not developed with 200 and 400 mg/kg toluene injections in c57 or c3h mice neither day,nor night. conclusion: differences of toluene induced reward seeking behavior in c3h mice at night may be related to the rhythmic melatonin release and circadian gene expression.