ROLE OF INTESTINAL ALKLINE PHOSHPATASE IN FAT TRANSPORT

Abstract

Digestion Absorption and intestinal transport of intraduodenally infused lipids were studied sequentially in the rat to define the mechanism responsible for marked increase in intestinal alkaline phosphatase in lymph following fat ingestion. Following infusion of lipids and fatty acids of various chain lengths, we found that the increase in intestinal alkaline phosphatase output in lymph was (1) not related to intraluminal fat digestion (2) not related to transport of long or short chain fatty acids cross mucosal brush borders; (3)not a structural part of lipoprotein particles in lymph but was (4) either related to triglyceride or lipoprotein synthesis in the endocytoplasmic recticulum or (5)closely involved with transport of lipoprotein through the cell and its passage cross plasma membranes into the interstitial space by reverse pinocytosis.