Immunolocalization of Parathyroid Hormone in Human Parathyroid Glands with Special References to Microwave Antigen Retrieval.

The subcellular localization of parathyroid hormone (PTH) in the normal human parathyroid glands with particular reference to microwave antigen retrieval was investigated using peroxidase-labeled PTH antibody, immunohistochemical, and immunoelectron microscopic methods. The results revealed that PTH granules existed mainly as pro-PTH on the trans side of Golgi and in the regions adjacent to Golgi apparatus. Only a small proportion of secretory granules were stored near the plasma membrane. Microwave irradiation was essential for the immunodetection of PTH. As the irradiative time extended from 1 to 30 min, the staining intensity increased, and the subcellular preservation decreased. Microwave irradiation for 15 mm (with the sections in citrate buffer) with a power output of 500 W is the most ideal for PTH antigen retrieval, as well as for subcellular preservation.