The central nervous system of Grillotia erinaceus (Cestoda: Trypanorhyncha) as revealed by immunocytochemistry and neural tracing.

Immunofluorescent labeling and neural tracing techniques were employed in conjunction with confocal scanning laser microscopy to study the intact neuroanatomy of the central nervous system of the trypanorhynch tapeworm Grillotia erinaceus. Immunocytochemical labeling for the general nerve fibre marker PGP 9.5 showed a pattern of extensive labeling that paralleled findings obtained with the neural tracer DiI. In contrast, immunocytochemical labeling for 5-hydroxytryptamine (5-HT) was localised to cell bodies lying on the periphery of the ganglion, with fine immunoreactive fibres radiating out towards the bothridia. Following the retrograde transport of the fluorescent molecule DiI through axotomised nerve cords, it successfully labeled both the cerebral ganglion and associated nerve fibres within the scolex. The cerebral ganglion was shown to give rise to posterior nerve cords, an array of radial fibres that pass out to the bothridia, and to contain a centrally disposed group of cell bodies thought to be involved in efferent functions.