Comparison of fat storage between Fischer 344 and obesity-resistant Lou/C rats fed different diets.
OBJECTIVE
We aimed to characterize further the Lou/C (LOU) and Fischer 344 (F344) rat strains for nutritional traits to validate their use as contrasting strains for molecular genetic studies.


METHODS
Five batches of LOU and F344 rats were used to measure caloric intake, weight gain, and body composition when fed a chow diet, a self-selection diet (together with the study of preferences for macronutrients), hypercaloric diets, and a chow diet in a cold environment.


RESULTS
Despite a higher caloric intake when fed a chow diet, LOU rats showed a lower weight gain, final body weight, and percentage of fat tissue, together with a higher percentage of carcass weight, than F344 rats. When fed a self-selection diet, LOU males ingested less protein and more fat than F344 males, and the reverse was observed for females. In this condition, feed efficiency was reduced in LOU but increased in F344 rats compared with the chow diet. Diet-induced obesity was observed in F344 rats but not in LOU rats fed hypercaloric diets. In a cold environment, both LOU and F344 rats displayed an increased percentage of brown adipose tissue compared with control groups, together with a higher caloric intake.


CONCLUSIONS
The study shows robust nutritional differences between the LOU rat, a lean strain with a low feed efficiency and resistant to diet-induced obesity, and the contrasting F344 rat strain. It also shows the interest in these strains for studying the genetic components of resistance to obesity.
Héliès
Jean-Marie
JM
Laboratory for Neurogenetics and Stress, UMR 1243 INRA, Université Victor Segalen Bordeaux 2, Bordeaux cedex, France.
Diane
Abdoulaye
A
Langlois
Allan
A
Larue-Achagiotis
Christiane
C
Fromentin
Gilles
G
Tomé
Daniel
D
Mormède
Pierre
P
Marissal-Arvy
Nathalie
N
D000273:Adipose Tissue / Q000502:physiology; D002001:Adipose Tissue, Brown / Q000502:physiology; D000818:Animals; D001823:Body Composition / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D004041:Dietary Fats / Q000378:metabolism*; D004435:Eating / Q000502:physiology; D002149:Energy Intake / Q000502:physiology; D005260:Female; D008297:Male; D009765:Obesity / Q000378:metabolism*; D009929:Organ Size / Q000502:physiology; D051381:Rats; D011916:Rats, Inbred F344; D017208:Rats, Wistar
D004041:Dietary Fats