Differences in the pharmacokinetics of cocaine in naive and cocaine-experienced rats

J Neurochem. 1991 Apr;56(4):1299-306. doi: 10.1111/j.1471-4159.1991.tb11425.x.


Enhanced cocaine concentrations in brain and blood observed after an intraperitoneal challenge dose in rats exposed to cocaine for 10 days by subcutaneous administration are traced to a change in the absorption process from the site of an intraperitoneal injection to general circulation. This conclusion is reached by three sets of corroborating results: (a) Adipose tissue of rats treated for 10 days with repeat subcutaneous injections of cocaine did not reveal a buildup of cocaine in sufficient concentrations to account for the twofold increase in brain and blood concentrations seen during intraperitoneal administration; (b) administration of the drug by an intravenous route after 10-day cocaine treatment did not show a significant difference between treatment and control groups; (c) nonlinear regression on the intravenous and intraperitoneal data sets using a two-compartment open model indicated a difference in the absorption process but not in the metabolic and blood-brain transfer processes.

Publication types

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

MeSH terms

  • Absorption
  • Adipose Tissue / metabolism
  • Animals
  • Cocaine / pharmacokinetics*
  • Drug Tolerance
  • Injections, Intraperitoneal
  • Injections, Intravenous
  • Male
  • Models, Biological
  • Rats
  • Rats, Inbred Strains
  • Regression Analysis
  • Time Factors


  • Cocaine