The Biochemistry Core Laboratory provides analytical support for the individual projects described in this Program grant application. The majority of the analytes required by the investigations described here are measured by manual radioimmunoassay (RIA). By having all the samples generated by individual investigators analyzed by staff with long experience with RiA techniques, in laboratories equipped with suitable instruments ,data can be obtained in a more uniform manner, with the strictest possible quality control and minimum of reagent expense. Samples from several investigators can be analyzed within one assay run, thus preventing the wastage which would be incurred by separate investigators analyzing small numbers of samples. Additionally, work can be scheduled more efficiently so that the technologists time is utilized with maximum efficiency resulting in almost no slack time. The projects of several investigators are worked on at the same time, thus reducing reagent costs, waste of labor and providing more uniform results.