PRECLINICAL STUDY: Correlation between serum ghrelin levels and cocaine‐seeking behaviour triggered by cocaine‐associated conditioned stimuli in rats

• DOI: 10.1111/j.1369-1600.2007.00052.x
• Publication Date: 2007-02-27T00:07:11Z
• Authors: Michela Tessari; Antonio Catalano; Michele Pellitteri; Carla Di Francesco; Francesca Marini; Philip A. Gerrard; Christian A. Heid...; Sergio Melotto
• Keywords: Corticosterone; Self-administration

Ghrelin is a brain-gut peptide with growth hormone-releasing and appetite-inducing activities. A growing body of evidence suggests that ghrelin may affect the central reward system modulate activity mesolimbic system. Recent clinical studies also showed significant positive correlation between plasma levels craving in alcoholics. Accordingly, present study investigated potential role serum reinstatement cocaine-seeking behaviour triggered by cocaine-associated cues. In addition, corticosterone were determined light suggesting plays modulatory behaviour. Male Lister Hooded rats under restricted diet regime first trained to intravenously self-administer cocaine fixed ratio-1 schedule reinforcement. Conditioned stimuli (CS: tone cue-light on for 5 seconds) presented contingently delivery. Once stable baseline self-administration was observed, lever presses extinguished less than 30% rates removing both CS. Reinstatement responding then induced re-exposure Blood samples enzyme immunoassay determination radioimmunoassay collected 30 minutes before beginning sessions. Rats significantly reinstated their when exposed observed (r = 0.64; P < 0.05), but not 0.37; NS), increased active only animals These findings suggest modulation cue-triggered