Histology demonstrated chromaffin cells in the head kidney and opisthonephros of the sea bass. Immunohistochemistry showed the catecholamine-synthesizing enzymes tyrosine hydroxylase and dopamine b-hydroxylase in these cells. Phenylethanolamine N-methyltransferase was detected in a fraction of the chromaffin cells in the head kidney (59%) and in the opisthonephros (54%). Distinct noradrenaline- and adrenaline-synthesizing cells are therefore suggested. Ultrastructural analysis confirmed the existence of two main chromaffin cell types, distinguished by different types of the secretory granules. Cells that contain vesicles with a round, electron-dense core were interpreted as noradrenaline cells, while cells with electron-lucent vesicles were identified as adrenaline cells. The ultrastructure of these chromaffin cell subtypes does not differ in the head kidney and opisthonephros. A minor population of chromaffin cells was identified, which typically show smaller vesicles with an electron-dense core. This population may account for a limited number of not fully differentiated chromaffin cells.
Immunocytochemical and ultrastructural evidence of adrenal chromaffin cell subtypes in sea bass Dicentrarchus labrax (L.).
ABELLI, Luigi;
1996
Abstract
Histology demonstrated chromaffin cells in the head kidney and opisthonephros of the sea bass. Immunohistochemistry showed the catecholamine-synthesizing enzymes tyrosine hydroxylase and dopamine b-hydroxylase in these cells. Phenylethanolamine N-methyltransferase was detected in a fraction of the chromaffin cells in the head kidney (59%) and in the opisthonephros (54%). Distinct noradrenaline- and adrenaline-synthesizing cells are therefore suggested. Ultrastructural analysis confirmed the existence of two main chromaffin cell types, distinguished by different types of the secretory granules. Cells that contain vesicles with a round, electron-dense core were interpreted as noradrenaline cells, while cells with electron-lucent vesicles were identified as adrenaline cells. The ultrastructure of these chromaffin cell subtypes does not differ in the head kidney and opisthonephros. A minor population of chromaffin cells was identified, which typically show smaller vesicles with an electron-dense core. This population may account for a limited number of not fully differentiated chromaffin cells.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.