a1 Department of Biochemistry, University of Tasmania, Box 252C, GPO Hobart, Tasmania 7001
a2 Commonwealth Scientific and Industrial Research Organization, Division of Human Nutrition, Kintore Avenue, Adelaide, South Australia 5000, Australia
1. Energy intakes, body-weights, body fat index, total body fat and interscapular brown adipose tissue (IBAT) were examined in adult male, spontaneously hypertensive, stroke-prone (SHR-SP) rats and normotensive Wistar/Kyoto (WKY) controls given one of four diets for 33 d: (a) a starch diet, (b) a starch diet and a sucrose solution drinking option, (c) an 80xenergy from fat (F80) diet, (d) the F80 diet and a sucrose drinking option.
2. The SHR-SP rats showed a complete resistance to obesity on all four diets. For the high-fat diet the WKY animals became markedly obese with approximately two-fold increases in body-weight gain and body fat index when compared with the SHR-SP rats. The gain in total body fat was also significantly greater. IBAT as a percentage of total body-weight did not differ between the WKY and SHR-SP groups.
3. Compared with the WKY animals, the SHR-SP rats showed a reduced food intake but had the same potential to gain weight from the high-fat diet.
4. It is concluded that the resistance to obesity by the hypertensive animals is the result of a diminished energy intake.
(Received November 12 1985)
(Accepted February 03 1986)