Observation on the changes of cerebral venules wall matrix in spontaneous hypertensive rat with high-salt diet / 中国脑血管病杂志

ABSTRACT

Objective To investigate the changes of wall matrix of the cerebral venules in the high-salt fed spontaneously hypertensive (SHR) rats. Methods Six SI1R and six Wistar Kyoto (WKY) male rats at the age of 10 weeks were experimented. Rats in the SHR group were given high-salt diet ( 1% sodium chloride drinking water and 4% high-salt) for 10 months,and rats in the WKY group were given normal drinking water and fed for 10months,The rats were all raised in the Institute of Neurology,Huashan Hospital, Fudan University. The feeding conditions were kept at a constant temperature of 22-24 and constant humidity of 55 ±5% ,with artificial light and shade for 12 h each. Morphological changes of cerebral small vessels were observed by hcmatoxylin-eosin (HE) staining. Venules were differentiated from arterioles through the presence of ot-smooth muscle actin. Immunofluorescence was performed to observe the expression of collagen I (COL I ) .collagen IV ( COLIV) ,fibronectin (FN) and laminin (LN) in cerebral venules. The brain tissue was divided into cortex,deep gray matter and hippocampus regions. The collagen deposition and expression of related extracellular matrix of venules in these regions were compared. Results ( 1) HE staining showed vascular remodeling of arterioles in high-salt fed SHR, which was consistent with the pathological characteristics of arteriosclerotic cerebral small vessel disease. ( 2) Compared with the WKY group,the high-salt fed SHR group showed obviously increased cerebral venules COL I deposition and LN expression (153 ± 12 ts. 106 ±8,/=3. 253 =0. 004; 135 ±11 vs. 99 ±9,1 = 2. 575,/' =0. 017); COLIV deposition had an increasing trend,but without statistically significant difference (118 ± 12 vs. 99 ± 4,t = 1. 508,/' = 0. 142). There was no significant difference in FN expression ( 104 ±4 vs. 101 ±3,/= 0.664,P =0.512). (3) Compared with the group,the SHR group had significantly increased deposition of COLlin cortex and deep gray matter venules (159 ± 15 vs. 108 ±7,/=3.075,/'=0.007; 139 ± 12 i5.96±9,/= 2. 868, P =0. 009); No statistically significant difference was found bftween the two groups in hippocampus region ( 169 ± 16 133 ±9 ,i = 1. 926,P =0.072) ;No statistical significance was found between the high-salt diet SHR group and the WKY group in COLIV and fibronectin deposi.ion of venules in these regions (P > 0.05);Compared with the group,the L\ expression of deep gray matter venules in the SHR group after high-salt diet was significantly increased (125 ± 12 vs. TJ ±5,1 =3.767,/J = 0.002) ,and there was no statistically significant difference in both cortical and hippocampal regions (138 ±18 vs. 109 ±7,/= l.460,/>=0. 174; 153 ± 16 m. 133 ± 13,/= 0.960, P = 0. 359) . Conclusions Tic expression of COL I and LN of cerebral venules wall was increased in the high-salt fed SHR. The COL 1 deposition was most significant in cortex and deep gray matter,and the LN deposition was mainly in deep gray matter.