The Cholinergic System and Nociception in the Primate: Interactions with Morphine.
Abstract
In experiment 1, the shock titration task was used to evaluate the antinociceptive properties of five different classes of cholinergic compounds in the Rhesus monkey. It was found that only scopolamine and high doses of physostigmine were effective in elevating the shock threshold. The apparent antinociceptive effect of physostigmine, however, was difficult to separate from its nonspecific behavioral depressant effect and was probably not related to an increase in cholinergic tone. Experiment 2 examined the interaction of morphine with arecoline, scopolamine, and physostigmine. Only scopolamine (0.05 and 0.1 mg/kg) and high doses of physostigmine (0.1 mg/kg) interacted with morphine in the shock titration paradigm. The multiplicative interaction of morphine with scopolamine was confirmed in experiment 3 over a wider range of doses. It was concluded that morphine and the cholinergic compounds produce antinociceptive effects through different mechanisms of the pain system.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1975
- Accession Number
- ADA010665
Entities
People
- Agu Pert