<b>SCANNING SPECTROPHOTOMETRY FOR DYNAMIC STUDY OF THE ORGAN OXIDATIVE </b><b>METABOLISM </b>

Abstract

Because mitochondrial metabolic control mechanisms have been studied largely under in vitro conditions, there is little experimental knowledge of how energy metabolism supports physiologically functioning cells in viva. To elucidate the metabolic correlation, studies of intact organs with their integral structure and function are required. The present study was undertaken to construct a measurement system that permits non-destructive monitoring of the dynamics of oxidation-reduction responses of the mitochondrial respiratory enzymes and coenzymes in sin: in living organs. This was attained by developing a. special spectrophotometer capable of recording in three dimensions--wavelength, optical density, and time. It consists mainly of a vibrating grating for monochromatic illumination and repeated scanning in the near-ultraviolet to visible region, two photomultipliers with a pair of light guides for conduction and detection of light, and a microprocessor for data processing. Evidence is presented that the instrument actually works satisfactorily in perfused rat liver. The evidence also indicated the presence of a risk in conventional dualwavelength spectrophotometry when applied to organs in vivo.