Immunocytochemical localisation of prolactin and growth hormone in the perinatal sheep pituitary: a morphological and quantitative study.

The proxidase anti-peroxidase immunocytochemical staining technique has been used to identify prolactin and growth hormone cells in pituitaries from fetal and neonatal sheep. The size of the secretory granules in these cell types has been measured using the image analysing computer Quantimet 720. The area size distributions of the fetal prolactin and growth hormone granules were compared with those in the neonate and the adult. It appears that the gestional age of the fetus may influence the size range of prolactin secretory granules.