Forskolin inhibition of glucose transport in bone cell cultures through a cAMP-independent mechanism.

Studies are presented demonstrating inhibition of glucose transport by forskolin in human MG-63 osteosarcoma cells as well as osteoblast-like cells derived from normal human trabecular bone and chick calvaria. The cAMP-stimulators parathyroid hormone, prostaglandin E2, and isoproterenol did not influence glucose transport. Benzyl alcohol, a membrane lipid fluidity modulator, also provoked inhibition of the glucose uptake rate. Effects of forskolin and benzyl alcohol were not additive. It is suggested that cAMP is not a mediator of glucose transport in bone cells, and that forskolin inhibits glucose transport via a cAMP-independent mechanism.