Rats of the JCR:LA-cp strain, which are homozygous for the cp gene (cp/cp), are obese, insulin-resistant and hyperinsulinemic. They exhibit associated micro- and macro-vascular disease and end stage ischemic myocardial lesions, and are highly stress sensitive. We subjected male cp/cp rats to pair feeding (providing the rats each day the amount of food eaten by matched freely fed animals), a procedure which alters the diurnal feeding pattern, leading to a state of intermittent caloric restriction. Effects on insulin, glucose and lipid metabolism, response to restraint stress, aortic contractile/relaxant response and myocardial lesion frequency were investigated. Pair fed young (12 week old) cp/cp rats had lower insulin and glucose levels (basal and following restraint), consistent with increased insulin sensitivity, but a greater increase in plasma non-esterified fatty acids, in response to restraint. These effects were unrelated to lipolytic rates in adipose tissue, but may be related to reduced fatty acid oxidation in skeletal muscle. Older (24 week old) pair fed cp/cp rats had significantly reduced plasma triglyceride levels, improved micro and macro vascular function and reduced severity of ischemic myocardial lesions. These changes indicate a significant amelioration of end stage disease processes in this animal model and the complexity of metabolic/physiological responses in studies involving alterations in food intake. The effects illustrate the sensitivity of the JCR:LA-cp rat, an animal model for the Metabolic Syndrome and associated cardiovascular disease, to the environmental and experimental milieu. Similar stress-related mechanisms may play a role in metabolically induced cardiovascular disease in susceptible human beings.