Effect of Triton WR-1339 on lecithin-cholesterol acyltransferase in the rat

The effect of Triton WR-1339 on activity of lecithin-cholesterol acyltransferase was measured in rat serum following addition of Triton to the serum in vitro or after intravenous injection of the detergent. The inhibitory effect of Triton WR-1339 on activity of lecithin-cholesterol acyltransferase when the detergent was added in vitro was dose dependent and appeared to result from a direct action on the enzyme rather than from a physical modification of the substrate by the detergent. The serum half-life ($\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$) of Triton WR-1339 injected intravenously in the rat was 23.1 ± 1.0 h. The inhibitory effect of Triton on serum LCAT activity when the detergent was given intravenously was also dose dependent and was reversed when the serum concentration of Triton decreased; under specific conditions, LCAT activity reached values higher than control. This behavior after treatment of the animal may be explained by increased concentration of the enzyme in the plasma, by stimulation of LCAT activity by the very low density lipoprotein or metabolites accumulating in the plasma of rats treated with Triton WR-1339, or by a combination of these factors.