[Aging and ovariectomy cause a decrease in brain glucose consumption in vivo in Wistar rats].

INTRODUCTION

The life expectancy of the population has been increased steadily over the twentieth century in both genders. The survival of women has always been higher compared to men and these differences in longevity are reproduced in other animal species such as rats. There must be some biological basis to support the differences in longevity between males and females. Differences can be explained by the effects of estrogens because ovariectomy cancels out the benefits shown in females compared to males.

AIM

Our aims were to study the cerebral glucose consumption in vivo in young and old female Wistar rats and evaluate the effect of ovariectomy on the brain glucose uptake.

MATERIAL AND METHODS

We used female Wistar rats, divided into young (4-7 months), young control (Sham) and ovariectomized (3 or 6 weeks) and old (22-24 months) groups. After intravenous administration of 18F-fluorodeoxyglucose (FDG) the cerebral glucose uptake was measured in vivo by Positron Emission Tomography (PET).

RESULTS

There was a significant decrease in cerebral glucose consumption in old rats compared with young rats. Similar results were found in glucose uptake when comparing control rats with ovariectomized rats, i.e., ovariectomy significantly reduces the brain glucose consumption.

CONCLUSIONS

Aging causes a decrease in cerebral glucose metabolism. Ovariectomy reduces cerebral glucose consumption significantly compared to control rats and is similar to the old group.