Histological, histochemical and immunohistochemical study on the structure of meibomian gland of adult male albino rat

ABSTRACT

Meibomian gland function is critically important in maintaining the health and integrity of the ocular surface. This gland, through its production and secretion of lipids, promotes the stability and prevents the evaporation of the tear film. Few researches had been published concerning the histochemical and immunohistochemical structure of this tissue. This study was carried out to highlight the structural characteristics of meibomian gland of adult male albino rat using histological, histochemical and immunohistochemical methods. The present study was carried out on 15 adult male albino rats. The upper eye lids of both sides were dissected out and the specimens of one side were processed for paraffin sections and stained with haematoxylin and eosin, Mallory's triehrome, Periodic acid Schiff's PAS] and immunohistochemical staining. The lids of the other side were frozen, in optimal cutti;g temperature compound, sectioned with cryostat and stained with oil redO. Haematoxylin and eosin stained sections showed the meibomian gland consisted of numerous branched acini, each acinus consisted of a basal layer of flattened cells and a mass of rounded cells with vacuolated cytoplasm. Mallory's trichrome stained sections showed the tarsal plate within which the meibomian gland was located. PAS stained sections showed PAS+ve reaction on the basement membranes surrounding the acini, Oil red O stained sections showed the acinar cells of meibomian gland distended with lipid droplets of variable color density. In addition, the acini of meibomian gland showed positive staining for estrogen and androgen rcccptors. It could be concluded that meibomian gland had positive staining with antibodies for estrogen and androgen receptors. Also, the lipid contents of the meibomian gland had variable color density