9809-1122 Liszka
Liszka TG, Dellon AL, Im M, Angel MF, Plotnick L.
Effect of lipectomy on growth and development of hyperinsulinemia and hyperlipidemia in the Zucker rat.
Plast Reconstr Surg. 1998 Sep;102(4):1122-7. PMID: 9734431
Division of Plastic Surgery at the University of North Carolina, Charlotte, USA.
The Zucker fat rat inherits obesity and hyperinsulinemia, exhibits insulin
resistance, and is, therefore, a model of adult onset, or type II, diabetes. The
purpose of this study was to determine if excision of fat depots from the infant
Zucker (fa+/fa+) rat would affect growth, fat cell number, hyperinsulinism, and
hyperlipidemia. In the experimental design, 10 percent of the total body weight
(inguinal and interscapular depots) was excised at 6 weeks of age from 18 fat
and 18 lean (fa+/fa-) litter mates, with 18 fat and 18 lean rats serving as
nonoperated controls. At intervals, serum glucose, insulin, cholesterol, and
triglycerides were measured. Initially, the operated fat group was significantly
(p < 0.01) lighter than the nonoperated group. By 9 weeks postoperatively, the
operated fat rat group had regained weight and continued to grow at the same
rate as the nonoperated fat rats because of intra-abdominal fat depots.
Lipectomy had no effect on growth rate of the lean rat group. Although lipectomy
caused no consistent change in serum glucose or insulin levels, it caused a
significant decrease in lipid levels. For example, the operated fat rats had a
reduction in cholesterol from 876 to 171 mg/dl by 15 weeks postoperatively, and
serum cholesterol persisted at about 50 percent of the nonoperated group
throughout the rest of the study (38 weeks postoperatively). Even a greater
reduction in triglyceride levels occurred, for example, from 7415 to 1082 mg/dl
at 24 weeks postoperatively. Lipectomy did not cause a change in lipid levels in
the lean group. It is concluded that the lipectomy in the Zucker fat group is an
excellent model to evaluate the effects of changes in fat cell number on lipid
metabolism.
|
