目的 探究微管骨架、水通道蛋白4(AQP4)和K+通道4.1(Kir4.1)在大鼠急性脊髓损伤后的时间变化规律。方法 90只成年雌性Sprague-Dawley大鼠,随机分组为假手术组(n=30)和损伤组(n=60),损伤组设6 h、1 d、3 d、5 d、7 d,每个亚组12只大鼠。用Allen打击法制备T10打击损伤模型。损伤后各时间点各组行脊髓含水量检测、脊髓HE染色,观察急性脊髓损伤后的病理变化;行微管蛋白、AQP4和Kir4.1免疫组织化学染色和Western blotting检测,观察急性损伤后三组蛋白的表达变化及相对灰度值分析。结果 损伤组各时间点脊髓含水量均高于假手术组(P<0.05),且5 d时最高。HE染色显示,损伤后6 h,灰质主要以出血为主;损伤后1 d,灰质出血严重,神经元肿胀加重;损伤后3 d,灰质坏死面积加大,水肿现象明显;损伤后5 d、7 d,灰质坏死更加明显,水肿现象更加严重。Western blotting和免疫组织化学染色结果显示,损伤后AQP4在灰质表达逐渐增高,且5 d表达为高峰,微管蛋白和Kir4.1表达趋势基本相同,为损伤后表达逐渐下降,5 d表达最低。结论 脊髓损伤后微管蛋白表达与Kir4.1表达趋势相似,与AQP4表达趋势相反,可能共同参与水肿形成。
陈铁戈
,
郭永强
,
王明
,
张东亮
,
夏亚一
,
汪静
,
伍亚民
,
党跃修
,
张海鸿
. 微管蛋白、水通道蛋白4和K+通道蛋白4.1在大鼠脊髓损伤后不同时间的表达变化[J]. 中国康复理论与实践, 2018
, 24(10)
: 1151
-1158
.
DOI: 10.3969/j.issn.1006-9771.2018.10.007
Objective To explore the expression and the changes of microtubule, aquaporin-4 (AQP4) and potassium ion channel 4.1 (Kir4.1) after spinal cord injury in rats.Methods Ninety female adult Sprague-Dawley rats were randomly divided into sham operation group (n=30) and injury group (n=60). The injury group was divided into six hours, one day, three days, five days and seven days subgroups, with twelve rats in each subgroup. Spinal cord injury at T10 was established with modified Allen's method (20 g×25 mm) in the injury group. The water content of spinal cord was measured at each time point after injury. Then, the pathology was observed with HE staining, the expression of α-Tubulin, AQP4 and Kir4.1 was detected and analyzed with immunohistochemical staining and Western blotting.Results The water content of the spinal cord was higher in the injured group than in the sham operation group (P<0.05), and was highest on the fifth day. HE staining showed that the gray matter hemorrhage at six hours after injury; one day after injury, the gray matter bled seriously, and neuron swelling was aggravated; three days after injury, the area of gray matter necrosis increased, and the edema phenomenon was obvious; five days and seven days after injury, the gray matter necrosis and the edema phenomenon were more serious. Western blotting and immunohistochemistry showed that the expression of AQP4 gradually increased after injury, and raised at peak on the fifth day; the expression of α-Tubulin and Kir4.1 was similar, and the expression gradually decreased after injury, especially on the fifth day.Conclusion The expression of α-Tubulin and Kir4.1 is similar after spinal cord injury, and is contrary to the expression of AQP4. α-Tubulin, AQP4 and Kir4.1 may be related after injury and may participate in the formation of spinal cord edema.
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