RT Journal Article
SR Electronic
T1 Ketamine self-administration by the rhesus monkey.
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 303
OP 309
VO 203
IS 2
A1 Moreton, J E
A1 Meisch, R A
A1 Stark, L
A1 Thompson, T
YR 1977
UL http://jpet.aspetjournals.org/content/203/2/303.abstract
AB Intravenously administered ketamine served as a reinforcer of self-administration behavior in rhesus monkeys during daily 2-hour sessions. When the dose of ketamine was varied over a wide range at fixed-ratio schedules of reinforcement of 1, 8 and 64, the response rate was an inverted U-shaped function of the dose. Maximal response rates occurred at progressively higher doses as the fixed-ratio size was increased; drug intake per session was positively related to the dose. When the ketamine dose was held constant and the fixed-ratio was increased in a geometric series, the response rate increased as the fixed-ratio was increased to FR 128 or FR 256; additional increases in fixed-ratio size produced abrupt decreases in response rates. Since the response rate increased linearly as the fixed-ratio was increased geometrically, drug intake was a decreasing function of the response requirement. With respect to magnitude of reinforcement and fixed-ratio response requirement, the data show that ketamine maintains self-administration behavior in a manner similar to that of a number of other drugs and conventional reinforcers.