My summer project intends to shed some light upon a prospective animal model of schizophrenia in sprague-dawley, rats which is based upon the administration of the neurotoxin domoic acid during the second week of the animal’s life. I accomplish this through the assessment of chemical changes within the brain that occur following domoic acid treatment using immunohistochemical procedures. The pathways of the brain that I am specifically investigating are those which use the neurotransmitter dopamine. To assess the changes occurring within these pathways, I am using immunohistochemistry to assess the levels of tyrosine hydroxylase and the D2 receptor for dopamine within the brains of these animals.  Tyrosine hydroxylase is the enzyme utilized in the rate determining step of the synthesis of dopamine, and the D2 receptor is an abundant receptor found within the brain. To have a better idea of when changes within this system occurs, I have adopted a timeline approach which consists of utilizing these immunohistochemical procedures at different stages of subject development. These times are: Postnatal Day(PD) 21, which is the time at which subjects are weened; PD36, a time defined as early adolescence in human; PD60, approximately corresponding to late adolescence/early adulthood; and PD90, approximately corresponding to adulthood.

 Current research in the Ryan/Doucette lab has been in the investigation of a prospective animal model of schizophrenia. This model is based on the administration of the neurotoxin domoic acid to rat pups during their second week of life. Previous research in the lab has shown that in adolescence and adulthood pups that have been administered domoic acid show symptoms that are found within the human clinical population of schizophrenics. However, it is unknown what exactly happens over the course of the rat’s development following domoic acid administration that cause the manifestation of these symptoms. Through my summer project there is hope that we may be able to uncover what exactly happens, and when it happens during development that causes these behavioural changes that are observed at adulthood.

 My most exciting thing that I have done thus far this summer has been the testing of a immunohistochemical procedure for the D2 receptor that I have developed myself from existing protocols found within the literature.