Catecholamine-containing neurons in Remak's ganglion: a developmental and tissue culture study

Summary

Development and maturation of the catecholamine-containing neurons of the embryonic chick and quail Remak's ganglion were studied, using the glyoxylic acid method. Fluorescent neurons were detected in the pararectal segment of the ganglion from its earliestin vivo formation, and along the whole ganglionic chain in later developmental stages. In tissue culture, a large number of catecholamine-containing neurons matured in expiants of both early and more developed ganglia, producing an extensive network of outgrowing fluorescent nerve processes. Pararectal ganglia, culturedin vitro for up to 4 days, gave rise, whatever the developmental stage examined, to fluorescent migratory neurons distributed either in ganglion-like clusters or singly in a large area surrounding the expiant. Many non-fluorescent neurons were intermingled with the fluorescent ones in the expiants, as well as in the outgrowth. Ganglia from segments adjacent to the small intestine did not give rise to migratory neurons whatever the developmental stage. Regional differences in the development of migratory neurons may be correlated to the mechanism of thein vivo organization of the ganglionic chain. The present observations indicate that catecholamine-containing neurons in Remak's ganglion exhibit the same histochemical features as adrenergic sympathetic neurons and differentiate in short-term cultures.