A. Cepedabenito et St. Tiffany, MORPHINE AS A CUE IN ASSOCIATIVE TOLERANCE TO MORPHINES ANALGESIC EFFECTS, Pharmacology, biochemistry and behavior, 46(1), 1993, pp. 149-152
This study examined the extent to which low doses of morphine paired e
xplicitly with high doses would gain associative control over toleranc
e development in rats. Tolerance development was assessed by evaluatin
g dose-response curves to the analgesic effects of morphine on the tai
l-flick test. The results indicated that tolerance development was not
influenced by the pairing of low doses with high doses.