[Techniques for isolating hair cells from guinea pig cochlea].

Isolated live hair cells are important models for studying the electrophysiology, pathology and pharmacology of the hair cell. Using mechanical isolation method after papain treatment 70 +/- 27 hair cells, including 0 to 4 inner hair cells, could be obtained from each cochlea of 4 guinea pigs. The criteria for a good viability of isolated cochlear hair cells were: 1. a smooth hair cell membrane; 2. hair cells not swollen; 3. the nucleus in the normal position; 4. the cytoplasm in a state of semitransparency with a halo at the periphery (birefringence) and 5. no Brownian movement of the organelles within the cytoplasm. With short-term culturing at room temperature, approximately 90% of the isolated hair cells retained a good viability at the end of two hours. Subsequently the hair cells gradually degenerated but still, at the end of five hours, about 40% of them appeared intact. The degeneration patterns have been carefully observed and described.