A multiple schedule model of limited access drinking in the cynomolgus macaque.
The present study reports on the development of a multiple schedule procedure of oral ethanol self-administration in cynomolgus macaques. Six adult cynomolgus macaques (four female, two male) were trained to self-administer ethanol and water under a 60 min, four-component multiple schedule of ethanol and water access with 1 g food pellets presented every 900 s (fixed-time 900 s). Water was available for the first and third 15 min components, ethanol in the second and fourth components. Total ethanol dose was stable at between 1-1.25 g/kg at ethanol concentration of 4%, 6% and 8%. Subsequently water was replaced with a sweetened drink (sugar-free Tang powder, General Foods). Ethanol and Tang were self-administered in similar volumes and both served as reinforcers compared with water. Acute pretreatment with 0.25 to 1.5 g/kg of intragastrically gavaged (i.g.) ethanol failed to alter ethanol or Tang self-administration significantly despite producing mean blood ethanol levels of up to 199 mg/dl when combined with self-administered ethanol. However, 1.0 g/kg i.g. ethanol administered for 15 consecutive days significantly decreased ethanol self-administration by 23%. The results suggest that ethanol self-administration under a multiple schedule is insensitive to alteration by acute ethanol pretreatment, but can be decreased by more prolonged chronic ethanol pretreatment.
Shelton
K L
KL
Department of Pharmacology and Toxicology, Virginia Commonwealth University, PO Box 980613, Richmond, VA 23298-0613, USA. klshelto@hsc.vcu.edu
Young
J E
JE
Grant
K A
KA
D000428:Alcohol Drinking / Q000523:psychology*; D000818:Animals; D002492:Central Nervous System Depressants / Q000097:blood / Q000494:pharmacology; D003216:Conditioning, Operant; D000431:Ethanol / Q000097:blood / Q000494:pharmacology; D005260:Female; D005502:Food; D007441:Intubation, Gastrointestinal; D008252:Macaca fascicularis; D008297:Male; D008960:Models, Psychological; D012055:Reinforcement Schedule; D012054:Reinforcement, Psychology; D014867:Water
D002492:Central Nervous System Depressants; D014867:Water; D000431:Ethanol