Schwann cell galactocerebroside induced by derivatives of adenosine 3′,5′-monophosphate

Indirect immunofluorescence was used to show the presence of galactocerebroside (galC), a lipid found in myelin, on the surface of about half of the Schwann cells isolated from neonatal rat sciatic nerves and cultured for 1 day without neurons. By day 4 in vitro, the Schwann cells had all lost their surface galC. Three days after beginning treatment with 10^-3 molar 8-bromo-adenosine 3′,5′-monophosphate (8-bromo cyclic AMP) or N ⁶,O²-dibutyryl adenosine 3′,5′-monophosphate (dibutyryl cyclic AMP), galC reappeared on the Schwann cells, and 2 days later 48 percent of the cultured Schwann cells showed surface galC. Tritium from tritiated D-galactose was incorporated into galC by the 8-bromo cyclic AMP-and dibutyryl cyclic AMP-treated cultures at a rate 15 times the control rate.