title: The effects of amphetamine and chlorpromazine on independent ingestion of milk in preweanling rats.
abstract: To assess the effects of catecholaminergic drugs on independent feeding during development, preweanling rats were administered amphetamine (AMPH) or chlorpromazine (CPZ) and were allowed to ingest milk through anteriorly located intra-oral cannulas. In 1-hr milk-deprived rat pups, AMPH stimulated milk intake at 3, 7 and 10 days of age and suppressed intake at 15 days. In 22-hr-deprived pups, AMPH had no effect at 3, 7 and 10 days, but reliably suppressed intake at 15 days. CPZ stimulated intake in 3-, 10- and 15-day-old milk-satiated pups. In 22-hr-deprived pups, CPZ had no effect at 3 and 10 days, but stimulated intake at 15 days. While AMPH produced pronounced nonappetitive behavioral activation in conjunction with enhanced intake in 1-hr-deprived pups, AMPH-induced activation occurred without enhanced intake in 22-hr-derived pups. Thus, there was a dissociation between AMPH's effect on milk intake and AMPH-induced nonappetitive behavioral activation. Collectively, the present results support the following conclusions. First, a catecholaminergic system(s) that enhances independent feeding is present very early in postnatal development of the rat. Second, level of food deprivation is an important state-dependent variable when assessing the effects of AMPH and CPZ on independent feeding in preweanling rats.
authors.affiliation: Department of Psychology, Fairleigh Dickinson University, Rutherford, NJ 07070.
authors.forename: C A
authors.initials: CA
authors.lastname: Capuano
authors.forename: G A
authors.initials: GA
authors.lastname: Barr
authors.forename: S F
authors.initials: SF
authors.lastname: Leibowitz
mesh_terms: D000367:Age Factors; D000661:Amphetamine / Q000494:pharmacology*; D000818:Animals; D000833:Animals, Suckling / Q000254:growth & development*; D002746:Chlorpromazine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005247:Feeding Behavior / Q000187:drug effects*; D005260:Female; D005508:Food Deprivation / Q000502:physiology; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D051381:Rats; D013997:Time Factors
chemical_list: D000661:Amphetamine; D002746:Chlorpromazine