ABSTRACT
This chapter presents a general overview of the in situ hybridization technique and its application to study of the functional anatomy of the central nervous system (CNS). It provides a conceptual overview of the basic principles, allowing implementation and interpretation of in situ experiments, from both a theoretical and practical perspective. Because of the potential power of this method as a quantitative tool, the chapter focuses on quantitative analysis schemes and protocols. The in situ hybridization method represents essentially the application of a molecular biochemical method toward solving problems of brain chemistry. The theoretical framework around which the in situ hybridization method is built is borrowed extensively from the dissociation-reassociation kinetics of DNA and RNA in solution. In situ hybridization protocols have become almost as numerous as the laboratories using them. One should initially start with one or two well-described techniques, which can then be tailored to the individual investigator's needs.
