No abstract

The distribution of succinic dehydrogenase (SDH) activity and the changes of SDH activity after injection of gentamicin (GM) were observed in the organ of Corti using non-decalcified frozen sections of the guinea pig's cochlea. The distribution of SDH activity was found to increase from the apex to the basal turn. At each turn, SDH activity of the inner hair cells, the inner supporting cells and the nerve endings surrounding the supporting cell and on the hair cells presented a greater activity than that found in the outer hair cells, adjacent Deiter's cells and associated nerve endings. It was further observed that GM had a greater effect on SDH activity in the basal turn than the other turns. At each turn, a more sensitive area of response to GM was found on the nerve endings one each hair cell, especially on the outer hair cells of the basal turn.

No abstract

We have developed a technique for sectioning temporal bones and have studied non-decalcified frozen guinea pig cochleas to localize succinic dehydrogenases. The technique is simple and practicable. The 6-microns sections used preserve both fine cochlear structure and satisfactory histochemical localization for identifying the succinic dehydrogenases. The technique can also be extended to immunological test, detecting transmitters and investigating enzymes in the cochlea.