We report the presence of four hemorphin peptides in extracts of normal adrenal tissue and in pheochromocytoma tumors. The hemorphins were quantified and structurally characterized using mass spectrometry. High concentrations of hemorphins were found in all samples, comparable with the levels reported in the literature for pituitary and brain tissue. The ultrastructure of adrenal medullar pheochromocytoma cells has no specific features, although these cells are characterized by morphological signs of high functional activity. Secretory granules of pheochromocytoma cells have variable morphology and electron density.
Granule content is released from cells by diffusion or exocytosis.
The structure of adrenocytes and noradrenocytes has features which allow to distinguish cell types from each other. Pheochromocytomas and extra-adrenal paragangliomas are tumors of the paraganglia with similar histological characteristics. The allelic deletions in chromosomes 1p and 3p appear to be separate events. Severe hemodynamic instability may occur during surgery for removal of pheochromocytoma, unless there is preoperative pharmacological treatment. The percentage of patients not requiring pressors or phentolamine during the intraoperative period as well as the perioperative peak systolic pressures and peak heart rates were estimated in each group.