Quantitative assessment of early experimental diabetes in rats using dynamic contrast-enhanced computed tomography.
OBJECTIVE
To quantitatively assess the time course of changes of the renal volume and function in the early phase of streptozotocin (STZ)-induced diabetes in rats using dynamic contrast-enhanced computed tomography (DCE-CT).


METHODS
The DCE-CT studies were performed in 24 male Sprague-Dawley rats (n=6 for control and n=18 for STZ-treated group) on days 0, 4, 7, 11, and 14 using a multi-detector row CT. The rats of an STZ-treated group were given intraperitoneally 65mg/kg body weight of STZ on day 0, and were divided into two groups based on the blood glucose concentration on day 4 being less than 300mg/dL [STZ-treated group (L), n=8] or greater than 300mg/dL [STZ-treated group (G), n=10]. The contrast clearance per unit renal volume (K(1)) was estimated from the DCE-CT data using the Patlak model. The renal volume (V(CT)) was calculated by manually delineating the kidney on the contrast-enhanced CT image. The contrast clearance of the entire kidney (K) was obtained by K(1)xV(CT).


RESULTS
V(CT) in the STZ-treated group was significantly enlarged on day 4 compared to that on day 0 and continued until day 14. Although there were no significant changes in the time course of K(1) in all groups, K in the STZ-treated groups (L) and (G) significantly increased on days 7 and 4, respectively, and continued until day 14, suggesting that hyperfiltration occurs in parallel with renal volume enlargement.


CONCLUSIONS
The present method appears useful for quantitatively evaluating the time course of STZ-induced diabetes in rats, because it allows repeated and simultaneous evaluation of renal morphology and function.
Department of Medical Physics and Engineering, Division of Medical Technology and Science, Faculty of Health Science, Graduate School of Medicine, Osaka University, 1-7 Yamadaoka, Suita, Osaka 565-0871, Japan. murase@sahs.med.osaka-u.ac.jp
Kenya
K
Murase
Akihiro
A
Kitamura
Atsushi
A
Tachibana
Yoshinori
Y
Kusakabe
Risa
R
Matsuura
Shohei
S
Miyazaki
D000818:Animals; D003287:Contrast Media; D003921:Diabetes Mellitus, Experimental; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis* / Q000503:physiopathology; D007668:Kidney / Q000473:pathology; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D051437:Renal Insufficiency; D013997:Time Factors; D014057:Tomography, X-Ray Computed
D003287:Contrast Media