Immunohistochemical Distribution of Prolactin Secreting Cells and Anti-S100 Cells in the Pituitary of the Rabbit Oryctolagus cuniculus and Guinea pig Cavia porcellus

The objective of the current study was to determine the immunohistochemical distribution and density of prolactin secreting cells and Anti-S100 cells of the pituitary gland in rabbit, Oryctolagus cuniculus and guinea pig, Cavia porcellus. The Immunohistochemical study indicated that prolactinsecreting cells were arranged in single, double or triple groups in the rabbit pituitary gland while they were mostly single cells in guinea pig. In both animals PRL-secreting cells were polymorphic in shape with centric or acentric nucleus. The Anti S-100 cells were scattered in pairs distalis. The S-100 positive cells sometimes had cytoplasmic processes between endocrine cells. Although PRL-secreting cells represent high percentage (44%) in the rabbit. There was no significant increase with t-value 1.11 and the probability was more than 0.05. Anti S-100 cells significally increased (54%) in guinea pig with t-value 2.46 as compared with the rabbit and the probability less than 0.05.