Succinate dehydrogenase activity in the wall of rabbit aorta. The histochemical use of PMS and exogenous coenzyme Q10 as intermediate carriers.

An investigation of succinate dehydrogenase activity in the wall of rabbit aorta was carried out. The level of succinate dehydrogenase per se in the smooth muscle cells was found to be fairly high, while the mitochondrial level of carrier CoQ was low. The latter may explain the low level or lack of activity of succinate dehydrogenase in these cells as noticed by previous authors. A reliable image of the actual level of succinate dehydrogenase was obtained only by adding CoQ10 to the incubation system. PMS should be avoided, as it induced a "Nothing dehydrogenase" reaction even at low concentrations.