Prolactin in the Cestodes, Taenia solium and Taenia hydatigena: an immunocytochemical study

The demonstration of prolactin in cestodes, Taenia solium and Taenia hydatigena, was investigated by using immunocytochemical method. PRL immunoreactivity was widely distributed in the CNS and PNS in the worms. In the scolex PRL-IR perikarya occurred in the cerebral ganglia, around the basic area of the sucker and the rostral border region between the rostellum and the suckers with strong immunoreaction, distinctly in Taenia solium. A number of PRL-IR nerve fibres were observed in the main nerve cords, and a few fibres in the transverse nerve commissure. The holdfast musculature of the scolex was innervated by the PRL-IR fibres. A large number of PRL positive cells with processes and nerve plexuses were seen in the ootype/Mehlis' gland complex, oviduct, the duct of uterum, seminal receptacle and its associated duct, conspicuously in Taenia hydatigena. PRL-IR was evident in the wall of vas efferens of tests and vas deferens. A few PRL positive cells occurred in the medullary parenchyma amongst testes and sent their varicose processes to terminate to the testes. On the wall of the main excretory duct a few PRL-IR cells and fibres were seen.