Mixed cocaine agonist/antagonist properties of (+)-methyl 4beta-(4-chlorophenyl)-1-methylpiperidine-3alpha-carboxylate, a piperidine-based analog of cocaine

J Pharmacol Exp Ther. 2003 Apr;305(1):143-50. doi: 10.1124/jpet.102.046318.

Abstract

The present study investigated the pharmacological properties of a piperidine-based novel cocaine analog, namely, (+)-methyl 4beta-(4-chlorophenyl)-1-methylpiperidine-3alpha-carboxylic acid [(+)-CPCA]. Like cocaine, (+)-CPCA inhibited rat synaptosomal dopamine and norepinephrine uptake with high affinity, but was 33-fold less potent than cocaine in inhibiting serotonin uptake. Like cocaine, (+)-CPCA is a locomotor stimulant, although it was less potent and efficacious than cocaine. Importantly, pretreatment with (+)-CPCA dose dependently blocked the locomotor stimulant effects of cocaine in rats. (+)-CPCA completely substituted for cocaine in drug discrimination tests, although it was about 3 times less potent than cocaine. It was also self-administered by rats. Unexpectedly, (+)-CPCA did not enhance cocaine-induced convulsions in mice. As expected from rodent studies, rhesus monkeys readily self-administered (+)-CPCA. However, compared with cocaine, (+)-CPCA showed limited reinforcing properties in rats as assessed by both fixed and progressive ratio intravenous drug self-administration tests. These results collectively suggest that (+)-CPCA has an atypical pharmacological profile having both cocaine-like "agonist" and some cocaine "antagonist" properties. These properties of (+)-CPCA suggest that it may have utility in the treatment of cocaine craving and dependence.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cocaine / agonists*
  • Cocaine / analogs & derivatives
  • Cocaine / antagonists & inhibitors*
  • Discrimination Learning / drug effects*
  • Humans
  • Infusions, Intravenous
  • Macaca mulatta
  • Mice
  • Motor Activity / drug effects*
  • Piperidines / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Self Administration

Substances

  • Piperidines
  • methyl 4-(4-chlorophenyl)-1-methylpiperidine-3-carboxylate
  • Cocaine