Cold storage (8 C) of islets of Langerhans in a high-potassium "intracellular medium": near-normal insulin release and morphology after one week.

Islets of Langerhans from ob/ob mice were microdissected and stored for one week at 8 C or 37 C in a high-potassium "intracellular medium" or in a traditional culture medium (RPMI 1640 +/- fetal calf serum). Subsequent glucose-stimulated insulin release and islet morphology were best preserved by 8 C-storage in the high-potassium "intracellular medium". This suggests that normal, adult, mammalian tissues which do not readily divide in vitro may be better preserved for short periods of time at refrigerator temperatures in a high-potassium medium than by conventional culture at 37 C in a tissue culture medium.