title: Experimental and clinical studies on plasma leptin in obese dogs.
abstract: Leptin is a protein synthesized and secreted primarily by adipocytes, and the circulating leptin concentration is elevated in obese humans and rodents. Recently, we have established a sandwich enzyme-linked immunosorbent assay for canine leptin. In the present study, plasma leptin concentrations were measured in experimentally developed obese beagles and in clinically obese dogs. When 5 male beagles were given a high-energy diet for 3 months, all of them became obese and the plasma leptin concentration significantly increased from 2.4+/-1.2 to 4.9+/-0.9 ng/ml, positively correlating with body fat content estimated by the deuterium oxide dilution method (r=0.87). The leptin concentrations of plasma samples collected from 59 dogs in veterinary practices were compared with their body condition scores (BCS). The plasma leptin concentrations of obese dogs were 9.7+/-0.7 and 12.3+/-1.5 ng/ml at BCS=4 and BCS=5, respectively, which were significantly higher than those of optimal (BCS=3) dogs (2.7+/-0.3 ng/ml). There was no significant effect of sex and breed. A weak positive correlation (r=0.37) was found between the plasma leptin concentration and age, probably due to the lesser content of visceral fat in puppies younger than 1 year old. These results indicate that plasma leptin is a good index of adiposity in dogs regardless of breed, age and sex, and may be useful for quantitative assessment of obesity in small animal practice.
authors.affiliation: Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
authors.forename: Katsumi
authors.initials: K
authors.lastname: Ishioka
authors.forename: Mohamed M
authors.initials: MM
authors.lastname: Soliman
authors.forename: Mayumi
authors.initials: M
authors.lastname: Sagawa
authors.forename: Fumio
authors.initials: F
authors.lastname: Nakadomo
authors.forename: Haruki
authors.initials: H
authors.lastname: Shibata
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Honjoh
authors.forename: Akira
authors.initials: A
authors.lastname: Hashimoto
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kitamura
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kimura
authors.forename: Masayuki
authors.initials: M
authors.lastname: Saito
mesh_terms: D000818:Animals; D001835:Body Weight; D004283:Dog Diseases / Q000097:blood*; D004285:Dogs; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D020738:Leptin / Q000097:blood* / Q000378:metabolism; D008297:Male; D009765:Obesity / Q000097:blood / Q000662:veterinary*; D012044:Regression Analysis
chemical_list: D020738:Leptin