EFFECT OF MILK-BORNE EPIDERMAL GROWTH-FACTOR ON THE HEPATIC MICROCIRCULATION AND KUPFFER CELL-FUNCTION IN SUCKLING RATS

Epidermal growth factor (EGF) is contained in breast milk, is transpor ted intact across the gastrointestinal mucosa during the suckling peri od, retains its biological activity, and affects hepatic growth. Wheth er or not EGF also influences postnatal hepatic development by affecti ng nonparenchymal cells or by modifying intrahepatic blood is not clea r, As a result, the effect of EGF on the hepatic microvasculature was studied in suckling rats fed rat milk substitute (RMS) with and withou t EGF (100 ng/ml, i.e. twice the normal intake in breast milk) between days 11 and 14 and compared to pups breast-fed for 14 days. The liver s of anesthetized pups were examined by in vivo microscopy to determin e the numbers of sinusoids with flow (SCF) in each of 10 microscopic f ields and the numbers of phagocytic Kupffer cells (KC) in the same fie lds followig an intraportal injection of fluorescent 1-mu m latex part icles, Phagocytic activity was expressed as the ratio KC/SCF. In pups fed RMS without EGF, SCF and KC/SCF was 75 and 45 %, respectively, of that in breast-fed animals, The addition of EGF to the RMS restored SC F and KC/SCF nearly to the levels measured in breast-fed pups, Thus, t he results suggest that milk-borne EGF plays a role in the development of KC phagocytic function and affects the amount of blood that perfus es the sinusoidal bed in the suckling.