Presence of neuroendocrine cells in the vestibular glands of the cattle and pig genital tract

Abstract The presence of neuroendocrine (NE) cells producing biogenic amines and hormonal peptides has been investigated in the vestibular glands of the genital tracts of cows and pigs using immunohistochemistry. NE cells containing chromogranin A-, serotonin-, cholecystokinin- and somatostatin-immunoreactive material were found in both major and minor vestibular glands. Such cells were numerous, scattered in the acini and excretory duct epithelium, small in size and rounded, triangular or bipolar in shape. The function of the NE vestibular cells has been related to the secretory activity of the glands and to a sexual climax induction mechanism involving the stimulation of 5HT(3) receptors of vestibular nociceptor nerve fibers. The role of NE cells in small cell carcinomas of the vestibular glands is a topic for further investigation owing to possible parallelism between this type of tumor and the small cell carcinoma of the human prostate.