Human and bovine HDL desensitize GC-B in GCB/3T3 cells. Human and bovine HDL preparations were added to GC-B/3T3 cells for 30 min and desensitization of GC-B was then determined as described under Methods. Fetal bovine serum (FBS) was diluted in PBS and cells treated as described for the HDL preparations. Results are the mean -/+ S.D. (n = 4).