Ultrastructrual and Cytocchemical Studies of Melanogenesis in Melanocytes of Normal Human Hair Matrix

Abstract

Combined ultrastructural and cytochemical studies were made to elucidate the origin and the mode of formation of pigment granules in the melanocytes of normal human hair matrix. The present study suggested the following processes of pigment granule formation. The proteinaceous material, rich in tyrosinase and synthesized at the ribosomes, are aggregated and concentrated in the peripheral part of cisternae of Golgi apparatus. They are then packaged into the amorphous or lamellarstructures and secreted into the cytoplasm by budding off from the dilated cisternae. The earliest premelanosomes in the melanocyte of normal human hair matrix are recognizable not as small vesicles but as large spherical vacuoles in the Golgi region.