Photodynamic effects of vital staining with diazine green (Janus green) on living bull spermatozoa

Abstract

1. 1. The effects of diazine® green (Janus green), a specific vital stain for mitochondria, on the total number of bull spermatozoa moving normally and on their mean velocity and velocity distributions were studied, using the photo-electric equipment described by Rikmcnspoel [12] and by Rikmenspoel and Van Herpen [14]. 2. 2. In the absence of light diazine green has no measurable effect on living bull spermatozoa in concentrations up to 200 p.p.m. (4 × 10 −7 M). 3. 3. Under illumination, diazine green acts as a powerful photosensitizer, decreasing the total number of normally moving spermatozoa as well as their mean swimming velocity. Both effects may be attributed to one single site of attack. 4. 4. The photosensitizing effect is strictly proportional to the number of dye molecules adsorbed per unit of susceptible area. The quantitative relationships are in agreement with a simple adsorptive process, following the empirical Freundlich equation and also the theoretically founded Langmuir adsorption isotherm. 5. 5. The velocity frequency distributions are not only shifted to lower values, but their shape is altered too. The top value of the normalised frequency curves rises and the standard deviation of the distribution is significantly decreased.