Js. Shumsky et al., EFFECTS OF DIET ON SENSITIZATION TO COCAINE-INDUCED STEREOTYPY IN FEMALE RATS, Pharmacology, biochemistry and behavior, 58(3), 1997, pp. 683-688
The progressive increase in cocaine-induced stereotyped behavior that
accompanies repeated cocaine injections (sensitization) was examined i
n rats consuming different diets. Adult female Sprague-Dawley rats wer
e fed one of three diets: low protein (6% casein), adequate protein (2
5% casein), or a standard chow diet. Following 1 week of adaptation to
the diets, the rats were injected every 3-4 days with either cocaine
(30 mg/kg, IF) or saline, and the total amount of stereotypy was measu
red over a 90-min interval following each of four injections. Cocaine-
induced stereotypy peaked at 40-50 min following each injection, alter
which it declined for all diet groups. With repeated injections, the
total amount of stereotypy increased in all diet groups, By the fourth
injection, the low protein diet group (6% casein) exhibited a slower
onset and a possibly prolonged duration of cocaine-induced stereotypy
when compared with the two adequate protein diet groups (25% casein an
d chow). Interestingly, the rats in the two pu rifled diet groups (6%
casein and 25% casein) exhibited significantly more stereotypy across
injections than those in the chow diet group. Weight differences did n
ot explain the differences in stereotypy present among the diet groups
, This study concludes that diet significantly alters the pattern of c
ocaine-induced stereotypy in female rats, especially after repeated ex
posure. (C) 1997 Elsevier Science Inc.