Experiments were performed in rats to evaluate the possible mechanisms responsible for the pharmacological cross-sensitization observed between repeated electroconvulsive shock (ECS) and chronic morphine administration. Repeated daily ECS for 9 days as well as chronic morphine pellet implantation resulted in a significant increase in the number of 3H-DADLE binding sites (Bmax values of 231 and 196 fmoles/mg protein, respectively). By contrast, single ECS, repeated sham ECS, and placebo pellet-treated rats all had significantly lower Bmax values (approx. 170 fmoles/mg protein). Affinities were not significantly altered by these treatments (Kd values between 3.1 and 4.0 nM). These data may link pharmacological cross-sensitization (repeated ECS and chronic morphine treatment) with a functional increase in the number of available opioid receptors.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Pharmacology, Toxicology and Pharmaceutics(all)