Effect of inhibition of carbohydrate-mediated endocytosis on catabolism of equine haptoglobin and its complex with haemoglobin in hen.

Equine haptoglobin (Hp) and haptoglobin-haemoglobin complex (Hp-Hb) are metabolised in the hen parenchymal cells of the liver in which endocytosis was inhibited by agalacto-orosomucoid (AGOR) or native orosomucoid (OR). The intravenous administration of AGOR or OR together with [125I]Hp slightly decreased clearance of Hp from circulation. This suggested that heterologous Hp could be catabolised by the alternative pathway following the uptake by the liver RES cells. Administration of the [125I]Hp-Hb complex and AGOR was of no effect on the clearance of the Hp-Hb complex.