Development and use of a nonrestraining waveguide chamber for rapid microwave radiation killing of the mouse and neonate rat

The use of microwave energy for rapid killing of small rodents such as the mouse or rat has become a standard pharmacologic technique since approximately 1975. This method allows investigation of rapidly modulated neurochemical indices, neuromodulatory substances, and some neurotransmitters to be determined at basal concentrations in brain regions and microregions. Previously described devices for use with microwave generators have relied on total body restraining holders in order to properly position rodents and neonates within a closed waveguide during microwave energy exposures. The present information describes two alternate chamber designs which do not require restraint of the rodent. A positioning device is described which must be used with the waveguide chambers. The animal chambers are designed to be used with 2450 MHz energy.