EFFECT OF AMYLOMAIZE STARCH ON PLASMA-LIPOPROTEINS OF LEAN AND OBESE ZUCKER RATS

Male Zucker rats either genetically obese (fa/fa) or lean (Fa/-) were fed a semi-purified diet containing either cornstarch or amylomaize st arch (Eurylon 7R) rich in amylose (70%). Obese rats were hyperlipidemi c (cholesterol, 3.27+/-0.18; triglycerides, 2.11+/-0.12 g/liter), when compared with lean rats (cholesterol, 1.13+/-0.03; triglycerides, 0.7 5+/-0.05 g/liter). The amylomaize diet did not reduce the body weight of the Zucker rats. However, it decreased weight, esterified cholester ol, and triglyceride content of the liver in both lean and obese rats. The amylomaize diet decreased plasma cholesterol levels of obese rats (-42%) and lean rats (-30%), while plasma triglyceride levels were si gnificantly decreased only in the lean rats (-43%). The cholesterol co ntent of chylomicrons, VLDL, LDL1 (1.006-1.040), and LDL2 (1.040-1.063 , which contains apo E-rich HDL) was reduced by 40 to 50%, while that of HDL was reduced by only 20% (lean) or 23% (obese). Diet containing amylose-rich starch therefore constitutes a promising new way of nutri tional control of hyperlipidemias.