Fine structure of the functional mesonephros in the eight-day chick embryo

摘要: An electron microscopic study of the functional mesonephros in 8-day chick embryo revealed following features nephron: Proximal tubule cells. Nuclei are spherical and basally oriented. Mitochondri round or elongate with clear-cut cristae. Intramitochondrial granules occur sporadically. The Golgi complex, lying adjacent to nucleus apical cytoplasm, consists flattened lamellae associated secretion droplets. cytoplasm is filled ribosomes which occasionally spiral arrangement. Characteristic microvilli project from end Basal regions cells bounded by a homogeneous basement membrane. Adjacent epithelial separated at their base wide intercellular spaces. Interdigitating processes between common this area. At apices, joined junctional complexes. Distal centrally located. Microvilli sparse usually absent. When present, they short blunt. Cells closely allied tightly apices. not as prevalent proximal tubules. Infoldings plasma membrane prominent compartmentalize mitochondria. Glomerulus. Endothelial elongate, bordering capillary lumen, membranes contain definite slit-pores. Epithelial pedicels extend cell body, intergiditate each other rest on latter three layers resembling those adults. The similarity fine structural characteristics adult metanepros corroborates holonephric theory vertebrate kidney evolution.