A method for restraining awake rats using head immobilization

A method for restraining awake rats using head implant immobilization is described. In order to reduce stress to the individual animal, rats were restrained side by side in pairs during the adaptation and experimental periods. This technique was used in studies of central regulation of cardiovascular function. In particular, microdialysis probes were placed stereotaxically in deep nuclei of the cerebellum while mean arterial pressure and heart rate were monitored in the awake rat. After initial habituation, normal levels of heart rate and blood pressure obtained during restraint indicated that this is essentially a nonstressful procedure. This technique could also be used for a variety of other experimental conditions where head movement is not desirable, such as during oculomotor or vestibular experiments.