RETRIEVAL OF ESTRADIOL-RECEPTOR IN PARAFFIN SECTIONS OF RESTING PORCINE UTERI BY MICROWAVE TREATMENT - IMMUNOSTAINING PATTERNS OBTAINED WITH DIFFERENT PRIMARY ANTIBODIES

The unmasking of estradiol receptor in paraffin sections of Bouin's-fi xed uterine tissue from ovariectomized gilts was attained with microwa ve treatment. Immunocytochemistry of the receptor was performed using a polyclonal or five monoclonal antibodies, two of which are commercia lly available, reacting with different domains of the protein and an a mplified-peroxidase system for detection. With five of the antibodies, a predominance of nuclear staining was observed in cells of endometri al glands, while one monoclonal antibody (13H2), reacting with the rec eptor's domain E, showed a preference for the cytoplasmic receptor. In stroma, all antibodies detected more receptor in nuclei than in cytop lasm. In epithelium, the commercially available antibody H222, our mon oclonals 13H2 and HT65, and the polyclonal antibody 402 demonstrated m ore receptor in cytoplasmic than in nuclear areas. In myometrium, the nuclei from longitudinal and ring muscles were definitely stained with the antibodies. We conclude that the accessibilities of the antibody epitopes of the receptor differ according to the functional uterine ce ll type.