[Long-term effects of insulin on the adipocyte conversion of Ob17-line cells]

The Ob17 cell line was established from the epididymal fat pad of ob/ob mice. Chronic exposure to physiological concentrations of insulin led to a net increase in lipogenic enzyme activities (EC50 = 1 to 3 nM). Proinsulin exerted the same effects at higher concentrations (EC50 = 10 to 30 nM). The mitogenic effects of both hormones appeared only at supraphysiological concentrations (EC50 = 300 nM). We conclude this was a net dissociation between the lipogenic and mitogenic effects of insulin during differentiation of the Ob17 cells.