Structure and function of the glandular vas deferens in Ascaris suum (Nematoda).

The glandular vas deferens in the linearly arranged male reproductive tract in Ascaris suum produces substances which cause marked morphological and physiological changes in the spermatozoa. The glandular secretions, presumably formed by the rough endoplasmic reticulum and Golgi saccules, are extruded from the cells and coalesce to form homogeneous masses in the gland lumen. In sexually inactive worms the secretory material is separated from the spermatozoa by a sphincter comprised of neuro-muscular-like cells. During copulation the sphincter lumen enlarges and the spermatozoa and sperm-activating glandular material are mixed and simultaneously transferred to the female worm.