Fish liver is constituted of hepatocyte cords pervaded by a network of sinusoids. In fish liver, macrophages tend to give rise to melano-macrophage centres (MMCs). The aim of this study was to: a) characterize histochemically Atlantic bluefin tuna (Thynnus thynnus L.) (ABFT) MMCs; b) evaluate the use of MMCs as indicator of health status. Liver samples were taken from: a) wild adult males captured by traditional traps in Sardinia and Morocco; b) captive adult males experimentally reared in sea cages in Spain; c) captive juvenile males commercially reared in Croatia. The samples were fixed in 10% formalin, dehydrated in ethanol and embedded in paraffin wax. Sections were stained with: haematoxylin-eosin, α-naphtyl acetate esterase (ANAE) for macrophages; Mallory's method for lipofuscin/ ceroid, Perl’s stain for hemosiderin; antibodies against vitellogenin (VTG) and cytocrome 450P1A (CYP1A) mono-ossigenase. MMCs showed lysosomial activity and contained lipofuscins/ ceroids and hemosiderin. MMCs density was higher in the Croatian group in comparison to the other two fish groups. Moreover, individuals with hepatocytes immunopositive to VTG and CYP1A were found only in the Croatian group, thus indicating the exposure of these fish to environmental pollutants. This study indicates a role of MMCs as metabolic dumps and confirmed their utility as biomarker of fish health state
Melanomacrophage centres as indicator of Atlantic bluefin tuna (Thynnus thynnus L.) “health state”
PASSANTINO, Letizia;Zupa R;Pousis C;JIRILLO, Emilio;CORRIERO, Aldo
2011-01-01
Abstract
Fish liver is constituted of hepatocyte cords pervaded by a network of sinusoids. In fish liver, macrophages tend to give rise to melano-macrophage centres (MMCs). The aim of this study was to: a) characterize histochemically Atlantic bluefin tuna (Thynnus thynnus L.) (ABFT) MMCs; b) evaluate the use of MMCs as indicator of health status. Liver samples were taken from: a) wild adult males captured by traditional traps in Sardinia and Morocco; b) captive adult males experimentally reared in sea cages in Spain; c) captive juvenile males commercially reared in Croatia. The samples were fixed in 10% formalin, dehydrated in ethanol and embedded in paraffin wax. Sections were stained with: haematoxylin-eosin, α-naphtyl acetate esterase (ANAE) for macrophages; Mallory's method for lipofuscin/ ceroid, Perl’s stain for hemosiderin; antibodies against vitellogenin (VTG) and cytocrome 450P1A (CYP1A) mono-ossigenase. MMCs showed lysosomial activity and contained lipofuscins/ ceroids and hemosiderin. MMCs density was higher in the Croatian group in comparison to the other two fish groups. Moreover, individuals with hepatocytes immunopositive to VTG and CYP1A were found only in the Croatian group, thus indicating the exposure of these fish to environmental pollutants. This study indicates a role of MMCs as metabolic dumps and confirmed their utility as biomarker of fish health stateI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
