Area of Study:
I have been working on cocaine self-administration in rats and investigated the effects of different pretreatments and environmental cues on their behavior (lever presses, response latencies, and locomotor activity) and dopamine levels in the brain using in vivo microdialysis. The influence of environmental cues on drug taking behavior is extremely important in the development of drug dependence. Objects, colors, sounds and other cues repeatedly present at the event of drug taking are eventually associated with the drug and its effect. Finally, this drug-conditioned cue can cause an effect on its own or alter the “normal” effect of the drug. Conditioned drug effects can go in opposing directions. While many animal studies have shown that cocaine causes drug sensitization, we find cocaine-induced conditioned tolerance under certain circumstances. This dichotomy to our findings is very challenging. However, one major difference between the majority of animal studies and ours is that most studies use experimenter-administered drug administration. This is a very important issue to address in the field of addiction research because drug dependent patients generally self-administer the drug of abuse and choose the amount of drug taken according to their “needs”. Many investigators using animal models do not factor in the influence of voluntary drug intake on behavioral and neurochemical responses. Therefore, I am currently working with two different groups of rats, of which one is allowed to self-administer cocaine while the second group is paired (yoked) with the first group and receives non-contingent infusions of cocaine under the same conditions. Additionally to conditioning and microdialysis, I am currently learning Golgi staining, a staining technique that will further allow me to look at cellular differences between the two groups of animals.