Caffeine dependence in rats: effects of exposure duration and concentration.
Groups of rats were chronically exposed to a 1.0-g/L caffeine solution for 5, 10, 15 or 20 days. Upon removal of caffeine, rats were given brief exposure to a novel flavour CS (withdrawal CS) followed by 12 days of plain water and then brief exposure to a second flavour CS (neutral CS). Only rats exposed to 20 days of caffeine strongly preferred the neutral CS to the withdrawal CS in a 2-bottle test. In Experiment 2, groups of rats were chronically exposed to caffeine at one of four concentrations (1.0, 0.5, 0.25, or 0.125 g/L) for 21 days, after which withdrawal and neutral CSs were established. Only rats that drank the highest caffeine concentration, 1.0 g/L, preferred the neutral CS to the withdrawal CS. This suggests that long exposure to a strong caffeine solution is required in order to induce dependence in rats such that a CS associated with the withdrawal of caffeine becomes avoided.
Dingle
Rachel N
RN
Dalhousie University, Halifax, Nova Scotia, Canada B3H 2J1. rdingle@dal.ca
Dreumont-Boudreau
Sarah E
SE
Lolordo
Vincent M
VM
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D002110:Caffeine / Q000009:adverse effects*; D000697:Central Nervous System Stimulants / Q000009:adverse effects*; D003214:Conditioning, Classical / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D019966:Substance-Related Disorders / Q000209:etiology*; D013997:Time Factors
D000697:Central Nervous System Stimulants; D002110:Caffeine