A transitional differentiation of glial cells of cultured corpus callosum caused by dibutyryl cyclic adenosine monophosphate

Abstract Fragments and dissociated cells of the corpus callosum of 12-day-old rats were cultured in Rose chambers in nutritient media. After addition of dibutyryl cyclic AMP (db-c-AMP) dissolved in media without calf serum, a temporary morphological differentiation of immature glial cells was observed. The first signs of differentiation were observed 30 min and ‘dedifferentiation’ to the original features 24–48 h after the addition of medium with db-c-AMP. If db-c-AMP was applied together with calf serum, no differentiation of glial cells was observed. Fourteen-day-old cultures, which were cultured for 3 days in the absence of serum did not exhibit improved differentiation of the glial cells. During early stages of cultivation in the medium without calf serum, however, diminished migration of cells and delayed maturation were observed. Repeated application of db-c-AMP after 24 h was without effect. Repeated addition of db-c-AMP after 6 days and even later resulted in a morphological differentiation of the glial cells again. Theophylline applied alone, or together with db-c-AMP had only a negligible effect on the differentiation of immature glial cells. The temporary morphological differentiation of immature glial cells caused by db-c-AMP was abolished by colchicine and vincristine but not by actinomycin D, cycloheximide and concanavalin A.