Development of the liver in the chicken embryo. I. Hepatic cords and sinusoids
Date
1992
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
John Wiley & Sons, Inc.
Abstract
Hemopoiesis in the liver of the chicken embryo begins on
day 7 of incubation (Hamburger and Hamilton Stage 30) and peaks on day
14 (Stage 40). During this time frame, the differentiation of hepatic cells was
examined by light microscopy, transmission and scanning electron microscopy,
and morphometry. The avian liver is a closely packed mass of dendriform
cords and discontinuous sinusoids. Hepatocytes are pyramidal in
shape, and they ring the bile canaliculi which run through the centers of
the cords. Semithin sections, made possible by infiltration and embedding
in glycol methacrylate, were stained with hematoxylin and eosin to assess
the general architecture of the organ and the lipid content of the hepatocytes
and by the periodic acid-Schiff reaction and hematoxylin to visualize
the cytoplasmic stores of glycogen. The number of hepatocytes with demonstrable
glycogen fluctuates erratically in early hemopoiesis, and the
proportion of glycogen-containing cells progressively increases as hemopoiesis
climbs to a peak. Most differentiating hepatocytes are devoid of
lipid droplets until Stages 39 and 40. From Stage 30 to 35, hepatocyte volume
falls to its lowest value. Subsequently (Stages 36 to 40), cell volume
increases and hepatocytes achieve a relatively uniform size. Ultrastructural
changes in the differentiating hepatocytes, including alterations to
the mitochondria, endoplasmic reticulum, and Golgi apparatus, are documented.
These morphological and morphometric findings on the prehepatocyte
population and hepatic vasculature cover 2 of the 3 elements deemed
critical to hepatic hemopoiesis in many vertebrates. o 1992 Wiley-Liss, Inc.
Description
Copyright held by publisher
Keywords
Biology
Citation
GENE K. WONG AND MICHAEL J. CAVEY "Development of the Liver in the Chicken Embryo. I. HEPATIC CORDS AND SlNUSOlDS" THE ANATOMICAL RECORD 234555-567 (1992)