Comparative anatomy of PACAP-immunoreactive structures in the ventral nerve cord ganglia of lumbricid oligochaetes.

ABSTRACT

By means of a whole mount immunocytochemical approach, the distribution patterns of pituitary adenylate cyclase-activating polypeptide (PACAP)-27 and PACAP-38 were identified in the ventral nerve cord (VNC) ganglia of the earthworms Eisenia fetida and Lumbricus terrestris. Each PACAP form appears to occur in a distinct neuron population. Positions of these populations, as well as numbers and sizes of the constituting neurons do not essentially differ between the two species. The data suggest that in Lumbricid Oligochaetes, PACAP-27 and PACAP-38 neuron populations may mediate distinct physiological processes.