Fast Fixation of Brain In Situ by High Intensity Microwave Irradiation:Application to Neurochemical Studies

Abstract

The levels of acetylcholine and choline were measured in various brain regions of the rat after fixation by microwave irradiation of the head and after decapitation and subsequent freezing in liquid nitrogen. Levels of acetylcholine were increased by approximately 50% after microwave irradiation, while choline levels were reduced. These biochemical findings were correlated with virtually complete loss of acetylcholinesterase and NA DH-diaphorase activity after 1 s exposure to micro- wave irradiation at a level of 5 kW.