PT  - JOURNAL ARTICLE
AU  - C E Lau
AU  - A Imam
AU  - F Ma
AU  - J L Falk
TI  - Acute effects of cocaine on spontaneous and discriminative motor functions: relation to route of administration and pharmacokinetics.
DP  - 1991 Apr 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 444--456
VI  - 257
IP  - 1
4099  - http://jpet.aspetjournals.org/content/257/1/444.short
4100  - http://jpet.aspetjournals.org/content/257/1/444.full
SO  - J Pharmacol Exp Ther1991 Apr 01; 257
AB  - Rats administered cocaine i.p. and p.o. (7.5-30 mg/kg) showed dose-related increases in locomotor (LM) and small-movement activities, with LM rates decreasing over the 2-hr session, except at the largest i.p. dose, for which rates were greater in the 2nd hr. Lidocaine p.o. (15-30 mg/kg) did not increase activity. Relating the area under the curve measures for serum cocaine (concentration-time) and LM activity (LM activity-time) for 2 hr postadministration indicated that cocaine was about twice as potent i.p., compared to p.o., in increasing LM activity. Cocaine (i.p. and p.o.) produced dose-related decrements in both discriminative motor control performance and in task work rate, whereas lidocaine p.o. did not. The motor control decrements produced by cocaine were approximately comparable by i.p. and p.o. routes, whereas effects on LM rates were much greater by i.p. than by p.o. administration. The effects of cocaine by both routes on LM rates were proportionally much greater than its effect on motor control performance. Changes in LM rates and motor control performance over the postadministration period were related to the pharmacokinetic features (maximum serum concentration, time to maximum serum concentration and elimination half-life) of cocaine observed for the routes explored (i.p., p.o. and s.c.). Tail-tip serum samples, although yielding conservative estimates of cocaine concentration, correlated well with trunk serum and brain cocaine levels.