Abstract
Despite the commonly held view that tolerance does not develop to the pupillary effects of narcotics, recent studies have demonstrated tolerance to heroin-induced miosis in humans and to morphine-induced mydriasis in the mouse. Previous studies in this laboratory have shown that morphine produces a dose-related mydriasis and fluctuation (large amplitude, irregular oscillations in pupil diameter) in the rat pupil; the present study was designed to determine if tolerance develops to these effects following subcutaneous implantation of morphine pellets. We found that there is, indeed, tolerance to the morphine-induced mydriasis, but it is not complete. Furthermore, statistically significant tolerance does not develop to morphine-induced fluctuations in the rat pupil.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 2469-2475 |
| Number of pages | 7 |
| Journal | Life Sciences |
| Volume | 28 |
| Issue number | 22 |
| DOIs | |
| State | Published - Jun 1 1981 |
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Pharmacology, Toxicology and Pharmaceutics(all)