CRYOPRESERVATION OF ISOLATED TROUT HEPATOCYTES - VIABILITY AND FUNCTION IN PRIMARY CULTURE

Isolated trout hepatocytes were frozen using a programmable freezer an d stored in liquid nitrogen. Satisfactory viability were obtained in c ryopreserved hepatocytes (CP) as judged by trypan blue exclusion (TB). The viability of primary cultures of CP hepatocytes, was compared wit h fresh cells using attachment efficiency (using TB), the rate of neut ral red uptake (NRU), metabolism of the tetrazolium salt (MTT), and me asurement of intracellular lactate dehydrogenase content (LDH). These results show that the activities of CP cells was lower than in fresh c ultures, but remained constant over 72 hr of culture (similar to 70%). The CP cultures retain the aspects of liver-specific function as show n by the induction of cytochrome P-4501A1 (CYP1A1) by 3-methylcholantr ene (3-MC) and Benzo[a]pyrene (B[a]P) exposure.