Neutering fats produces fat cats

[Guest guest]

Hi All,

The below not PDF of Medline available seems to say: Neutering fats produces

fat cats. CR reduces sex hormones too, but not body fat. Do we express

variation in our bodies when we have the same level of CR and different

levels of sex hormones?

Cheers, Al.

J. Nutr. 133:1866-1874, June 2003

Weight Gain in Gonadectomized Normal and Lipoprotein Lipase–Deficient Male

Domestic Cats Results from Increased Food Intake and Not Decreased Energy

Expenditure

Marc L. Kanchuk, C. Backus3, C. Calvert*, G.

and Quinton R.

Gonadectomy predisposes domestic cats to undesired body weight gain and

obesity. The disturbance responsible for this disregulation of energy

balance has not been clearly identified. Energy intake and expenditure, body

composition and plasma concentrations of leptin, insulin, glucose and

triacylglycerol were determined during a 36-wk period in adult male (2–5 y)

gonadectomized (n = 8) and intact (n = 8) normal cats and gonadectomized (n

= 8) and intact (n = 8) lipoprotein lipase (LPL)–deficient cats. Cats were

housed individually in temperature- and light-controlled rooms and

continuously provided a commercial dry-type diet. In normal and

LPL-deficient cats, body weight increased (P < 0.05) after gonadectomy by 27

to 29%, mostly as a result of fat accretion. There was a rapid increase (P <

0.05) in food intake of 12% after gonadectomy of normal and LPL-deficient

cats. The metabolic rate (kJ·kg-1·d-1), determined in normal intact (319 ±

20, n = 5) and gonadectomized (332 ± 36, n = 5) cats, did not differ after

gonadectomy. After gonadectomy, plasma concentrations of glucose and

triacylglycerol did not change, whereas plasma insulin and leptin

concentrations increased (P < 0.05), but not coincidentally with body weight

gain. A stair-step increase in energy intake, and not decreased energy

expenditure, appears to drive the weight gain associated with gonadectomy.

Body fat mass appears to increase until the energy intake supports no

further expansion. Adiposity signaling through insulin or leptin does not

appear to mediate the energy intake effect. LPL deficiency did not preclude

development of the overweight body condition. Therefore, gonadectomy-induced

weight gain in cats is not a result of changed adipose LPL activity, as

previously suggested.

Alan Pater, Ph.D.; Faculty of Medicine; Memorial University; St. 's, NL

A1B 3V6 Canada; Tel. No.: (709) 777-6488; Fax No.: (709) 777-7010; email:

apater@...