This line was established from a primary culture of Syrian hamster islet cells which were transformed with SV40.The cells secrete up to 24ng of insulin in per 10 exp6 cells per 24 hours(passage 60).Insulin in secretion is stimulated by glucose and glucagon, and is suppressed by somatostatin and glucocorticoids.Insulin synthesis decreases with length of time in culture.Tumorigenecity:Isoenzyme:Histopathology:Subculture:Remove medium, add fresh 0.25 % trypsin (enough to cover the monolayer) and let stand at room temperature until the cells detach. Add fresh medium, aspirate and dispense into new flasks at about 1.3 X exp5 cells per sq.cm.Split ratio:Media change:Reverse transcritase:Productioninsulin