C. Cioni et al., MORPHOLOGY AND IMMUNOHISTOCHEMISTRY OF THE CAUDAL NEUROSECRETORY-SYSTEM OF A MARINE EURYHALINE FISH, DICENTRARCHUS-LABRAX, ACCLIMATED TO LOW-SALINITY, Italian journal of zoology, 63(1), 1996, pp. 13-22
The morphology and the immunohistochemistry of the caudal neurosecreto
ry system of Dicentrarchus labrax were analysed after the fish acclima
tation to fresh water. Two different sized neurosecretory cells have b
een identified in seawater-acclimated fish and denoted as anterior and
posterior cells. The two types of cells share similar patterns and in
tensities of immunoreactivity with urotensin I and urotensin II antise
ra. Posterior neurosecretory cells decreased in size in freshwater-acc
limated specimens, whereas anterior cells did not show changes. Urophy
ses of seawater- and freshwater-acclimated fish reacted with both anti
sera. Immunohistochemistry of the urophysis did not provide evidence f
or a significant difference in the activity of the caudal neurosecreto
ry system between seawater- and freshwater-acclimated fish. Ho Never,
on a morphological basis it was possible to suggest that the caudal ne
urosecretory system of the sea bass is involved in the hyperosmoregula
tion.