Investigation of aquaporin-1 expression and diffusion weighted imaging with multiple b values in adrenal gland in a rat model of diabetes mellitus
10.3760/cma.j.issn.1005-1201.2017.08.012
- VernacularTitle:糖尿病大鼠肾上腺水通道蛋白1表达特征以及多b值扩散加权成像评估肾上腺损伤的价值
- Author:
Yu WANG
;
Heng ZHANG
;
Ruzhi ZHANG
;
Ziqian XU
;
Lei WANG
;
Rongbo LIU
;
Fabao GAO
- Keywords:
Diabetes mellitus;
Magnetic resonance imaging;
Adrenal gland
- From:
Chinese Journal of Radiology
2017;51(8):616-620
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the character of aquaporin-1(AQP-1)expression in adrenal gland in diabetes mellitus and evaluate adrenal gland damage and function alterations by DWI with multiple b values. Methods Twenty male Sprague-Dawley rats were randomly selected by computer and randomized into 2 groups:untreated controls(n=10)and diabetes(DM)(n=10). Rats in diabetes group were fed with high-sucrose and high-fat diet, controls were fed with common diet. After fed with high-sucrose and high-fat diet for 4 weeks, rats in diabetes group were injected with streptozotocin(STZ). Forty days after diabetes induction with streptozotocin(STZ), MR imaging was performed in a 7.0 T scanner. Venous blood from the tails was collected before MRI scan to measure blood glucose, blood glucose more than 16.7 mmol/L wasregarded as diabetic status. All the rats underwent DWI with 18 b values(0 to 4500 s/mm2). Maps of pure diffusion coefficients(D), pseudo-diffusion coefficients(D*)and ultra-high ADC(ADCuh)were acquired. Rats were sacrificed after MRI scan for adrenal gland histopathology, AQP-1 immunohistochemistry analysis and AQP-1 optical density(OD)measurements. Student t test was used to compare the difference of D*, D, ADCuh and OD of AQP-1 between two groups. Results Eight diabetic animals developed hyperglycemia(two rats died during the modeling process). MRI scan was performed in all of the 18 rats. Signal intensity of D*map, D map and ADCuh map decreased gradually. ADCuh increased significantly in DM animals(0.24 ± 0.06) × 10-3mm2/s compared with control animals(0.18 ± 0.07) × 10-3 mm2/s(P<0.05), whereas there was no significant difference found between the two groups in their respective D*and D values(P>0.05). There was a noticeable increase in the AQP-1 labeling in the adrenal cell membrane and cytoplasm in DM animals compared with control animals. DM rats showed an increased OD value of AQP-1 in adrenal gland compared with the control animals(P<0.05). Conclusions We found significantly higher AQP-1 expression in adrenal gland in DM animals compared with controls. Ultra-high b-Values DWI may work as a useful way for noninvasive evaluation the change of adrenal function in DM.
