par Franckson, Jean ;Ooms, Henri
Référence Postgraduate medical journal, 49, 7 sup., page (931-939)
Publication Publié, 1973
Article révisé par les pairs
Résumé : Anesthetized dogs were infused with graded amounts of crystalline and labeled insulins by the 'priming dose constant infusion' technique. Catheters were inserted into the aorta, the renal, portal and hepatic veins, the thoracic duct, the main bile duct and the bladder. Hepatic, portal and renal blood flows were estimated. Parameters studied included total, hepatic and renal metabolic clearances of cold and labeled insulins, urine, bile and lymph excretions, regional balances or radioiodine. Measurements were carried out in steady state; a range of insulinemia from 50μ U/ml to 6 U/ml was tested. The kinetics of insulin catabolism by the kidney was not significantly influenced by the increase in concentration and by the iodination of the hormone; the degradation of the molecule was rapid and complete leading to a release of free iodide balancing the uptake of labeled insulin. The hepatic rate of catabolism was rapidly altered by increasing the plasma level and by iodination. The labeled insulin taken up was only partially degraded to free iodide and partially remained trapped within hepatic tissues. The physiological role of both pathways which normally account for more than 90% of total catabolism is discussed with regard to their chemical characteristics.