SIGNIFICANCE OF WITHDRAWAL JUMPING RESPONSE IN PREDICTING PHYSICAL DEPENDENCE IN MICE

Abstract

The significance of the naloxone-induced jumping response in predicting the physical dependence capacity of morphine-like analgesics was investigated in mice treated with morphine, morphine-6-glucuronide and pentazocine. The jumping response was induced by naloxone in mice chronically treated with morphine and morphine-6-glucuronide, but its development is not necessarily related to the number or frequency of drug injections, and it was also observed even after a single dose of the drugs. The jumping was not precipitated in mice chronically treated with pentazocine. The naloxone-induced jumping response in mice treated with morphine was not masked by morphine, but was markedly suppressed by chlordiazepoxide, diazepam, methamphetamine, delta-9-tetrahydrocannabinol and diphenylhydantoin. It is concluded that the naloxone-induced jumping response is not a specific abstinence phenomenon in mice treated with morphine-like analgesics, although it may be used for a first screening test to estimate a physical dependence capacity.