ISSN: 2161-1017
Atteyat Selim and Eman El Nahass
The immunocytochemical and the ultrastructure identification of the pituitary gland of many species of herbivorous mammals were few in Egypt and may be in the world, so the present study is carried out on some herbivorous mammals such as Oryctolagus cunniculus in order to elucidate the similarities and the differences of the pituitary cells in rabbits and some mammals of the world and those of Egypt. The results indicate that, the gland is pyramidal in shape and its apex is long, directed posterior and its base interiorly directed. The acidophilic and the basophilic cells distributed heterogeneous in the body of the gland. The identification of the cells based on specific morphological characterizes, staining reaction and immnuocytochemistry. (STH) Somatotropin: Numerous, the nucleus is central, irregular or lobed with chromatin granules. The secretary granules are very enormous and more denser. Luteotropic Hormone (LTH): The nucleus is eccentrically near the plasma membrane, the mitochondria are spherical or elongated. Rough ER is poor and the granules are light and mostly collected at the periphery of some cells. (ACTH) Adrenocorticotropic: These cells are found singly, round with eccentric nucleus. Secretary granules are small and spherical shaped, while the (TSH) Thyroid Stimulating Hormone: with very small secretary granules but the (FSH and LH) Follicle Stimulating Hormone and Luteinizing Hormone: are found singly, angular in shape with eccentric nucleus and the secretary granules are spherical or ovoid in shaped and exhibit variation in electron density than STH cells. We can differentiate between them by immune reactivity.