Immunohistochemical studies on the poll gland of the dromedary camel (Camelus dromedarius) during the rutting season

The poll glands are subcutaneous exocrine glands located on the back of the neck behind the ears in male camels. The function of poll glands is not well known, though they are thought to play a role during the rutting season. The presence, location and degree of immunolocalization of microfilaments and intermediate filament systems: actin and cytokeratins (Cks) and also S100 protein were studied in the poll glands in sexually mature one-humped camels during the rutting season. These proteins were variably expressed between the epithelia, perialveolar, interalveolar tissue and the periductal tissue. Strong α-smooth muscle actin (α-SMA) immunoreactivity (IR) was displayed by the perialveolar myoepithelial cells, periductal and vascular smooth muscle cells (SMCs), but not in the epithelial cells. Cytokeratin (Ck)-IR was strong in the epithelial lining of the secretory alveoli and excretory ducts, however, the apical blebs of the secretory cells were almost negative. Weak to moderate Ck-IR was observed in the perialveolar myoepithelial cells, but not in the interalveolar tissue or endothelial cells. S100 protein was expressed variably in the epithelial lining of the secretory alveoli. S100-IR was more obvious in the supranuclear region and the apical blebs. Variable reaction was observed in the perialveolar myoepithelial cells, periductal and interductal tissue and endothelial cells.