Prolactine cells of rat anterior pituitary gland were studied with the electron microscope in thin sections and freeze-etch replicas after treatment with norethisterone-oenanthate. A pathological secretory process is caused in this cell type in rats, when treated with this compound. Prolactine cells grow in number and volume of single cells. This is especially due to an enormous proliferation of the Golgi apparatus. In the same time, however, exocytosis of hormonal secretory granules is apparently reduced. Therefore, serum hormone level remains nearly normal.
PIP: Prolactin cells from the pituitary gland of female rats were studied under the electron microscope and by the freeze-etch method after treatment with norethisterone enanthate. Prolonged treatment caused a pathological secretory process in this type of cells. They increase greatly both in number and in volume, and particularly the Golgi apparatus proliferates. At the same time, however, exocytosis is reduced, and for this reason the serum prolactin level is also greatly reduced.