MICROWAVE APPLICATIONS IN CLASSICAL STAINING METHODS IN FORMALIN-FIXED HUMAN BRAIN-TISSUE - A COMPARISON BETWEEN HEATING WITH MICROWAVE ANDCONVENTIONAL OVENS

The quality of microwave adaptations of three classical neuroanatomica l staining methods (the Nissl, Kluver-Barrera and Haggqvist stains) wa s tested on frozen serial sections from human brain specimens which ha d been stored for up to 10 years in 10% formalin. The conclusion was t hat the use of microwave irradiation reduces processing time and/or co ncentrations of the chemicals used, whereas the light microscopical qu ality of the stains considered is equal or improved as compared to the ir original counterparts. Next, a comparison was made between microwav e adapted stains and classical procedures, which, except for the use o f a conventional oven as heat source together with pre-heated solution s, were entirely identical. It appeared, that at light microscopical l evel no difference can be appreciated between the effect of internally (using microwave irradiation) and externally (using a conventional ov en) supplied heat on the staining result.