Effect of testosterone on atherogenesis in cholesterol-fed rabbits with similar plasma cholesterol levels.
The aim was to examine the effect of testosterone on atherogenesis in cholesterol-fed, castrated male rabbits not mediated via different plasma cholesterol levels. The rabbits in the testosterone group (n = 19) and in the placebo group (n = 17) were injected intramuscularly twice weekly for 17 weeks with 25 mg testosterone enantate and placebo, respectively, reaching plasma testosterone levels of 50-150 nmol/l in the testosterone group. No effect of testosterone on liver function or body weight was detected, but at week 15 mean blood pressure was 75 +/- 2 mmHg (mean +/- S.E.) in the testosterone group compared with 69 +/- 2 mmHg in the placebo group (P < 0.05). To reduce variation in plasma cholesterol between the two groups, the amount of cholesterol fed to each rabbit was adjusted on the basis of weekly determinations of plasma cholesterol; the mean plasma cholesterol levels during the 17 weeks were 20.9 +/- 1.0 and 20.4 +/- 0.9 mmol/l for the placebo and testosterone groups. In the intima-inner medias of the aortic arch, the thoracic and the abdominal aorta there were no consistent significant differences in aortic cholesterol content, expressed either as nmol/cm2 or nmol/mg protein, between the two groups. However, the aortic cholesterol content tended to be lower in the testosterone group than in the placebo group. These findings suggest that in cholesterol-fed, castrated male rabbits, testosterone does not promote atherogenesis by an effect directly on the arterial wall.
Larsen
B A
BA
Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Denmark.
Nordestgaard
B G
BG
Stender
S
S
Kjeldsen
K
K
D000818:Animals; D001011:Aorta / Q000378:metabolism*; D001161:Arteriosclerosis / Q000378:metabolism* / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight; D002784:Cholesterol / Q000097:blood* / Q000378:metabolism; D002791:Cholesterol, Dietary / Q000008:administration & dosage*; D008111:Liver Function Tests; D008297:Male; D011817:Rabbits; D013739:Testosterone / Q000097:blood / Q000494:pharmacology*
D002791:Cholesterol, Dietary; D013739:Testosterone; D002784:Cholesterol