抄録
In these several years, histological studies at cellular level have been growing as the result of development in fluorometric technique. It is, however, rather difficult to carry out comparative, quantitative fluorometry for the sake of data processing largely relying upon photographic and biochemical analyses.
In this paper, 2 types of methods, the ideal filter method and the correlation method, are discussed with special reference to overcoming the difficulty involved in measurement of a very weak fluorescent light in the tissue. As the theoretical consequence the correlation method is shown to be effective in measuring a very weak fluorescence of a sample under microscope. The principle of the correlation method is as follows : The fluorescent light emanating from the sample being chopped, the chopped signal is detected and amplified by a photomultiplier. On the other hand, the reference signal with the same frequency is generated synchronously. The amplified signal is multiplied by the reference signal continuously. The multiplied output is integrated. Finally the intensity of the fluorescence is read on an ammeter or voltmeter. On the basis of the principle described above the authors devised an electrical fluorophotometer, which has been proved to function effectively through several experiments.
The present series of experiments has clarified that the difference in intensity of fluorescence in tissue is determined corresponding to the difference in serotonin (5-HT) concentration, and that the fluorescence in the tissue is composed of 2 components, the autofluorescence and the singular fluorescence that decays exponentially when the sample is continuously exposed to ultraviolet ray. It has been also made clear that the time constant of the decreasing fluorescence depends upon the nature of the substance.
This photometer possesses the aperture of 0.7 mm, and is set up on the position of the microscope camera.
