Original article
Insulin and hepatic
cholestasis during the early post-embryonic development of gilt-head sea
bream, Sparus aurata
J.-P. Diaz, E. Guyot, L. Mani-Ponset, R. Connes-2002
Aquatic Living Resources, 15(5): 283-292
Abstract:
This work is aimed at demonstrating the influence of
insulin in the triggering of hepatic cholestasis in young gilt-head sea
bream larvae reared under experimental conditions. The results are based on
an immunological assay of insulin and an ultrastructural study of the yolk
syncytial layer and the liver. Compared to fed larvae, fasting gilt-head sea
bream larvae displayed a substantial increase in insulin level correlated
with dysfunction of the yolk syncytial layer and hepatic histopathology.
This correlation was verified in larvae reared in sea water containing
insulin. Ultrastructural observations suggested that insulin affects
lipoprotein secretion by the yolk syncytial layer. The failure of plasmatic
lipoproteins would then cause dysfunction of the biliary lipid secretion
mechanisms and, hence, trigger hepatic cholestasis. These results in
gilt-head sea bream show for the first time the influence of insulin in the
triggering of hepatic cholestasis during the early development of a
vertebrate.