Laser photosensitization and metabolic inhibition of tissue culture cells treated with quinacrine hydrochloride.

LASER PHOTOSENSITIZATION AND METABOLIC INHIBITION OF TISSUE CULTURE CELLS TREATED WITH QUINACRINE HYDROCHLORIDE M. W . Berns, S . E1-Kadi, R . S . Olson and D. E . Rounds Department of Zoology, University of Michigan Ann Arbor, Michigan and The Pasadena Foundation for Medical Research Pasadena, California (Received 1 June 1970; in final form 27 July 1970) In a preliminary report (1) it was suggested that nucleolur function could be probed by treatment of tissue culture cells with quinacrine hydrochloride followed by laser microirradiation . Apparently the quinacrine associates selec tively with the nucleolus, thus making this organelle susceptile to selective damage by laser microirradiation . If the laser technique is to be useful for studying nucleolur function, the metabolic effects of the photosensitizing agent (quinacrine) must be elucidated . In addition, since previous studies have suggested shifts ïn absorption characteristics of other amino acridines (2) when bound in vitro, it is important to determine if such shifts occur with quinacrine . This is particularly important in selecting the appropriate wavelengths for microirradiation . In this manuscript we will present data : (a) indicating the quinacrine hydrochloride has only a temporary effect on nucleolur function ; (b) on the in vitro absorption spectrum of quinacrine hydrochloride .