PLASMA TRANSPORT OF LIPIDS AND LIPOPROTEIN PROTEINS IN DOGS TREATED WITH TRITON WR-1339*

Abstract

Dogs on a regular diet were given 250 mg of Triton WR-1339 (a non-ionic surface active agent) IV every 4th day. During the stage of sustained hyperlipemia (3rd to 4th week), the animals were injected with one of the following materials - lipoproteins labeled with either cholesterol-4-C14 or P-32phospholipids, Cl4-labeled chylomicron triglycerides, Il31-Triolein, albumin-palmitate-1-C14, I131-Triton, or lipoprotein labeled in the protein moiety with I131. Normal dogs served as controls. The results obtained concerning the time course of plasma disappearance and plasma distribution of the injected labeled materials tend to support the following conclusions (1) Triton administration slows markedly the egress of triglycerides from plasma, (2) in Triton-treated dogs, plasma accumulation of cholesterol and phospholipids is likely to secondary to an increase of their rate of production in liver or extra-hepatic tissues, (3) Triton affects the plasma partition of plasma turnover, (4) lipoprotein protein metabolism of Triton-treated dogs is within normal limits. It is suggested that Triton acts primarily on the lipoprotein lipids transforming them into foreign bodies taken up preferentially by the RES, in turn leading to an increased mobilization of fats from the peripheral tissues. This may furnish an explanation as why dogs after prolonged treatment with Triton develop lipidosis and depletion of fat stores (Scanu, A. et al., Jour. Exptl. Med. 114: 279, 1961).