The cytochemical localization of succinic dehydrogenase in the sperm mitochondria of the gastropod Biomphalaria glabrata. A comparison of two methods

The mitochondrial derivative of the sperm of the gastropod pulmonate Biomphalaria glabrata was studies to ascertain succinic dehydrogenase localization cytochemically. Two techniques were compared. One technique depends on a tetrazolium salt that yields an osmiophilic formazan upon reduction. The other technique is dependent on the reduction of copper ferricyanide. The effects of several electron transport inhibitors were studied. The reaction product observed in the matrix of the mitochondrial derivative using the former technique is sensitive to rotenone and is believed to be nicotinamide adenine dinucleotide-dependent. The reaction product observed in the intracristal spaces using the copper ferricyanide method is insensitive to rotenone and is believed to cytochemically demonstrate succinic dehydrogenase in this material.