Abstract
The temperature during microwave irradiation in the core of tissue blocks, either 1cm or 2cm cubes of rat kidney and liver, was measured by plunging a sensor into the tissue blocks. The temperature of the tissue blocks was much higher than the outer media, i.e., chemical fixatives. Thus, the temperature of the outer media did not reflect that in the tissue block to be fixed. The temperature of tissue reached 40°C within 5-10sec of irradiation. The highest temperature of tissuee block at 15-second irradiation, for example, was 92.5°C (1cm cube of kidney) and 98°C (2cm cube of liver), using 4% PFA with CaCl2 as a fixative. Microwave fixation is a practical tool for the preparation of tissue spections for either histology or cytology. However, it must be required that the irradiation is controlled so as not to produce high temperature within specimens.
