Artificial cold exposure induced stroke in renovascular hypertensive rats and its association with cold-inducible RNA binding protein mRNA expression in brain tissue and blood pressure

BACKGROUND： High incidence of stroke at interchange period of autumn and winter was demonstrated by epidemiological survey, and the specific causes should be further investigated. OBJECTIVE： To investigate the influence of artificial cold exposure on the incidence of stroke in renovascular hypertensive rats （RHR）, and analyze the association with blood pressure and cold-inducible RNA binding protein （CIRP） mRNA expression in brain tissue. DESIGN： A completely randomized grouping design, a randomized control animal trial. SETTINGS： Lab of Neurology, the First Affiliated Hospital of Sun Yat-sen University; Department of Chemistry, Open laboratory of Chemical Biology, Institute of Molecular Technology for Drug Discovery and Synthesis, University of Hong Kong. MATERIALS： Male SD rats （n=460）, weighing 80 - 100 g were obtained from Guangdong Province Health Animal Unit. A modified RXZ-300A intelligent artificial climate cabinet （Ningbo Jiangnan Instrument Co. ,Ltd., China）. METHODS： The experiment were processed in the Lab of Neurology, the First Affiliated Hospital of Sun Yat-sen University and the Open Laboratory of Chemical Biology, Institute of Molecular Technology for Drug Discovery and Synthesis, University of Hong Kong from October 2004 to November 2005. Rats （n = 400） were operated to establish 2-kidney 2-clip RHR model as described previously. The sham-operated rats （n =60） served as normotensive controls. Eight weeks later, 300 of RHR were randomly selected according to their systolic blood pressure （SBP） and divided into 3 sub-groups （n =100 per group）： mild hypertensive group （SBP of 160 - 200 mm Hg）, moderate hypertensive group （SBP of 200 - 220 mm Hg） and severe hypertensive group （SBP 〉 220 mm Hg）. Each group was further divided into two groups （n =50） under ACE and non-ACE. Normal sham-operated SD rats （n =60）, SBP 〈 140 mm Hg, were randomly divided into two groups： Sham-operated control group （n =30） under ACE and non-ACE. To establish the ACE and non-ACE treatment, rats were housed individually in artificial climate cabinet, and ACE was designed as three cycles of 12-hour light of 22℃ （7 ： 00 - 19 ： 00） and 12-hour dark of 4℃（19 ： 00 - 7 ： 00）. The non-ACE group was kept at 22℃ throughout the experiment. MAIN OUTCOME MEASURES： Blood Pressure changes were measured and stroke symptom were observed; Expression of the CIRP were examined by reverse transcription-polymerase chain reaction. RESULTS： Finally 360 rats were involved in the analysis of results. ①Incidence of stroke： The incidence of stroke in 2k2c RHR was significantly higher after a three-day intermittent （12-hour） ACE （29.3%） as compared with that in non-ACE （17.3%） （P 〈 0.05）. Furthermore, the severe hypertensive 2k2c RHR （BP 〉 220 mm Hg） was found to have much higher incidence of stroke （66%, 33/50） than the mild （8%, 4/50） and moderate （18%） hypertensive 2k2c RHR. ②CIRP mRNA in brain tissue： ACE treatment stimulated the mRNA expression of CIRP in non-stroke 2k2c RHR but not in stroke 2k2c RHR （P 〈 0.05）. CONCLUSION： High blood pressure and low expression of CIRP are associated with ACE induced stroke.

Effects of cervical low-frequency electrical stimulation with various waveforms and densities on body mass,liver and kidney function,and death rate in ischemic stroke rats

Low-frequency electrical stimulation has resulted in favorable effects in the treatment of post-stroke dysphagia. However, the safety of cervical low-frequency electrical stimulation remains unclear because of numerous nerves and blood vessels in the neck. In the present study, rats with ischemic stroke underwent low-frequency electrical stimulation, and systemic and local effects of electrical stimulation at different densities and waveforms were investigated. Electrical stimulation resulted in no significant effects on body mass, liver or kidney function, or mortality rate. In addition, no significant adverse reaction was observed, despite overly high intensity of low-frequency electrical stimulation, which induced laryngismus, results from the present study suggested that it is safe to stimulate the neck with a low-frequency electricity under certain intensities.

Middle cerebral artery occlusion methods in rat versus mouse model of transient focal cerebral ischemic stroke

Experimental stroke research commonly employs focal cerebral ischemic rat models （Bederson et al., 1986a; Longa et al., 1989）. In human patients, ischemic stroke typically results from thrombotic or embolic occlusion of a major cerebral artery, usually the mid- dle cerebral artery （MCA）. Experimental focal cerebral ischemia models have been employed to mimic human stroke （Durukan and Tatlisumak, 2007）. Rodent models of focal cerebral ischemia that do not require craniotomy have been developed using intraluminal suture occlusion of the MCA （MCA occlusion, MCAO） （Rosamond et al., 2008）. Furthermore, mouse MCAO models have been wide- ly used and extended to genetic studies of cell death or recovery mechanisms （Liu and McCullough, 2011）. Genetically engineered mouse stroke models are particularly useful for evaluation of isch- emic pathophysiology and the design of new prophylactic, neuro- protective, and therapeutic agents and interventions （Armstead et al., 2010）. During the past two decades, MCAO surgical techniques have been developed that do not reveal surgical techniques for mouse MCAO model engineering. Therefore, we compared MCAO surgical methods in rats and mice.

Effects of genetic and environmental factors and gene-environment interaction on expression variations of genes related to stroke in rat brain

To determine if genetic and environmental (dietary) factors and gene-environment interaction impact on the expression variation of genes related to stroke, we conducted microarray experiments using two homozygous rat strains SHRSR and SHRSP fed with high and low dietary salt levels. We obtained expression data of 8,779 genes and performed the ranking analysis of microarray data. The results show that the genetic difference for stroke in rat brain has a strong effect on expression variations of genes. At false discovery rate (FDR) ≤ 5%, 534 genes were found to be differentially expressed between the genotypes resistant and prone to stroke, among which 304 genes were up-regulated in the resistant genotype and down-regulated in the prone genotype and 230 were down-regulated in the former and up-regulated in the latter. In addition, 365 were functional genes for transcription and translation, receptors (in particular, neurotransmitter receptor), channels of ions, transportation, metabolism and enzymes, and functional and structural proteins. Some of these genes are pivotal genes that cause stroke. However, dietary salt levels and GE interaction do not strongly impact on the expression variations of these genes detected on arrays.

POTENT HYPOTENSIVE EFFECTS OF ORPHANIN FQ IN CONSCIOUS STROKE-PRONE SPONTANEOUSLY HYPERTENSIVE RATS

Orphanin FQ（OFQ） or nociceptin is a novel neuropeptide consisting of 17 amino acids. This peptide has a primary structure reminiscent of that of opioid peptide but exhibits an opposite effect to make animals hyperreactive. The effect of this new peptide on cardiovascular function are not completely known. The present study was conducted to investigate the effect of intravenous bolus injection of orphanin FQ on mean arterial blood presure （MABP） in conscious stroke-prone spontaneously hypertensive rats (SHRsp). Adult male SHRsp and Wistar normotensive rats （250～300 g body weight, 2. 5～3 months old） were used in this study. The MABP was measured in the conscious state by a tail-cuff method. In SHRsp model, intravenous bolus injection of orphanin FQ or Tyr1-orphanin FQ （0. 5 mg/kg） induced a prolonged and marked reduc- tion in MABP. The maximum changes in MABP were -30. 2±4. 2 mmHg by orphanin FQ and -28. 2± 4. 7 mmHg by Tyr1-orphanin FQ at 10 min after administration,and this effect lasted over 30 min. The Phe1→Tyr substitution in orphanin FQ was found to retain almost fully hypotensive activity. Pretreatment of SHRsp with naloxone-HCI（60 μg/kg）, 5 min before the injection of orphanin FQ, did not block the hy- potensive effect of orphanin FQ. Therefore, opioid receptors could not account for the hypotensive effect of orphanin FQ in SHRsp. In Wistar rats, intravenous bolus injection of the same dose of orphanin FQ did not cause a change in MABP. These observations suggest that orphanin FQ is a novel hypotensive peptide and may have some role in the regulation of blood pressure in SHRsp, rather than in normotensive rats. The ex-act underlying mechanisms are waiting to be clarified.

Effect of 2-Selenium Bridged β-Cyclodextrin,Glutathione Peroxidase Mimic on Stroke of Stroke-prone Spontaneously Hypertensive Rats

To investigate the treatment effect of 2-selenium bridged β -cyclodextrin(2-SeCD),a GPX mimic,on the stroke of stroke-prone spontaneously hypertensive rats(SHRSP),fifty-two SHRSP of 8-week old were randomly divided into four groups A,B,C and control group D. The rats of groups A,B,C and D were given 1.0%-1.5% NaCl mass fraction as drinking fluid. After onset of stroke,groups A,B and C were given \{orally\} 16.05,160.5 and 1605 mg·kg -1 ·day -1 of 2-SeCD,respectively,and group D was given water for \{2 weeks.\} The clinical score of stroke,systolic blood pressure(SBP),survival time of rats were recorded and the histopathologic examinations of their brain and carotid artery were made after decapitation. The clinical scores of stroke after treatment with 160.5 mg·kg -1 ·day -1 (Group B) and 1605 mg·kg -1 ·day -1 (Group C) of 2-SeCD are 2.55±0.98 and 1.98±0.79,respectively,those are obviously lower than that of group D(3.41±0.83,p<0.01). The survival days in group B(10.0±8.6) and group C(14.4±7.9) are longer than that for group D(4.7±2.9,p<0.01). The electron microscope study showed that the endothelium of carotid artery was near to normal in group B and group C,while it was seriously injured in control group D and mildly injured in group A. 2-SeCD may effectively be used to treat the stroke for SHRSP.

Protective Effects of Nobiletin on Hypertension and Cerebral Thrombosis in Stroke-Prone Spontaneously Hypertensive Rats (SHRSP)

Some citrus flavonoids have been reported to possess antioxidant activities that moderate endothelial dysfunction and show protective effects on cardiovascular disease. We have investigated the protective effects of nobiletin (5,6,7,8,3’,4’-hexamethoxy flavone) derived from the peel of Citrus depressa Hayata (Shiikuwasha), a citrus fruit produced in Okinawa prefecture in Japan on hypertension and thrombogenicity in cerebral vessels of stroke-prone spontaneously hypertensive rats (SHRSP). Nobiletin was added to the diet of male SHRSP (7 weeks old) for 4 weeks. The age-related increase in systolic blood pressure usually observed in SHRSP was significantly suppressed in the treated animals. Thrombogenesis in pial blood vessels, determined using a He-Ne laser technique, and antioxidant activity, assessed by measuring urinary 8-hydroxy-2’-deoxyguanosine (8-OHdG), were significantly reduced after treatment. Urinary nitric oxide (NO) metabolites and acetylcholine-induced endothelial relaxation were increased after dietary intervention. These results strongly suggested that antihypertensive and antithrombotic effects of nobiletin may be related to an increase in bioavailable NO, possibly mediated by the scavenging of reactive oxygen species (ROS).

Dietary <i>γ</i>-Aminobutyric Acid Shortens the Life Span of Stroke-Prone Spontaneously Hypertensive Rats

Dietary γ-amino butyric acid (GABA) has been suggested to decrease systolic blood pressure. This study aimed to ex-amine the effects of dietary GABA on the life span of stroke-prone spontaneously hypertensive rats (SHRSPs). In this study, life span was determined for SHRSPs provided 1% NaCl solution or 0.01% GABA in 1% NaCl solution as drinking water. The life span of the GABA-fed group (76.3 ± 1.65 days) was significantly shorter than that of the control group (81.6 ± 0.88 days). The results of this study may not be applicable to humans. Future studies will be necessary to elucidate the mechanism underlying this phenomenon.

PERIPHERAL TISSUE DISTRIBUTION OF ORPHANIN FQ PRECUSOR mRNA IN STROKE-PRONE SPONTANEOUSLY HYPERTENSIVE RATS

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苦参碱对缺血性脑卒中大鼠神经炎症的影响

目的探究苦参碱调节高迁移率族蛋白B1(HMGB1)-晚期糖基化终末产物受体(RAGE)信号通路对缺血性脑卒中(IS)大鼠神经炎症的影响。方法将75只SD大鼠随机分为模型组、苦参碱低剂量组(10 mg/kg)、苦参碱高剂量组(20 mg/kg)、苦参碱高剂量+晚期糖基化终末产物(AGE)血清蛋白组(20 mg/kg苦参碱+100 mg/kg AGE血清蛋白)和假手术组,每组15只。采用线栓法构建大鼠大脑中动脉闭塞模型。用Longa评分评估大鼠神经功能缺损;氯化三苯四氮唑染色检测脑梗死情况;苏木精-伊红染色观察海马组织病理变化;酶联免疫吸附测定海马组织白细胞介素(IL)1β、IL-6、肿瘤坏死因子α(TNF-α)水平。Western blot检测海马组织HMGB1、RAGE蛋白表达。结果苦参碱高剂量组Longa评分、脑梗死面积、IL-1β、IL-6、TNF-α、HMGB1和RAGE蛋白表达明显低于模型组和苦参碱低剂量组(P<0.05)。苦参碱高剂量+AGE血清蛋白组Longa评分、脑梗死面积、IL-1β、IL-6、TNF-α、RAGE蛋白表达明显高于苦参碱高剂量组[(2.93±0.30)分vs(1.10±0.12)分,(38.18±4.04)%vs(15.52±1.74)%,(78.57±8.33)pg/ml vs(39.27±4.76)pg/ml,(203.14±24.39)pg/ml vs(92.45±11.23)pg/ml,(243.53±26.81)pg/ml vs(150.49±18.79)pg/ml,0.73±0.07 vs 0.44±0.04,P<0.05]。结论苦参碱可能通过抑制HMGB1-RAGE信号通路减轻IS大鼠的神经炎症。

探究电针廉泉穴对脑卒中后吞咽困难大鼠神经功能缺损的影响

目的探讨电针廉泉穴对脑卒中后吞咽困难(PSD)大鼠神经功能缺损的影响及潜在对瞬时受体电位香草酸亚型1(TRPV1)信号通路的调节机制作用。方法选用SPF级SD雄性大鼠60只,随机分为正常组12只(仅浅插栓线,未导致脑内动脉闭塞),余48只制作PSD模型,将造模成功的36只大鼠随机分为模型组、治疗组和治疗+咖啡酸组,每组12只。记录大鼠吞咽潜伏期和吞咽次数,生物信号采集器检测舌下神经放电、舌肌阈强度和收缩幅度,酶联免疫吸附测定血清P物质含量,甲苯胺蓝染色检测舌下神经核尼氏体数目,免疫组织化学检测舌下神经核TRPV1、五羟色胺(5-HT)、磷酸化p38、神经元型一氧化氮合酶(nNOS)蛋白表达水平。结果与正常组比较,模型组大鼠吞咽潜伏期、吞咽次数、舌下神经放电积分面积、舌肌收缩幅度、血清P物质含量、舌下神经核尼氏体数目、TRPV1及5-HT蛋白表达水平下降,舌肌阈强度和舌下神经核磷酸化p38、nNOS蛋白表达水平增加(P<0.05);与模型组比较,治疗组大鼠舌肌单收缩幅度、舌肌强直收缩幅度、血清P物质含量、舌下神经核尼氏体数目、TRPV1及5-HT蛋白表达水平增加[2.36±0.26 vs 1.77±0.22、3.46±0.36 vs 2.15±0.18、(3.92±0.38)ng/ml vs(1.69±0.17)ng/ml、(33.60±3.65)个vs(24.60±2.34)个、(19.85±2.11)%vs(9.79±1.07)%、(22.43±2.34)%vs(10.85±1.13)%,P<0.05]。结论电针廉泉穴可能通过激活TRPV1信号通路改善PSD大鼠神经功能缺损。

间充质干细胞外泌体对缺血性脑卒中大鼠神经功能恢复的影响

目的探讨间充质干细胞外泌体(MSCs-EXO)对缺血性脑卒中大鼠神经功能恢复的影响。方法大鼠骨髓间充质干细胞原代培养,超速离心法提取其MSCs-EXO,大脑中动脉夹闭模型(MCAO)法制作大鼠缺血性脑卒中模型,MSCs-EXO经鼻给药,设为MSCs-EXO组,通过改良神经功能缺损评分(mNSS)和错步试验评估其神经功能恢复情况,并与未治疗模型组(MCAO组)做对比。PKH26标记MSCs-EXO并结合免疫荧光染色观察其在缺血半暗带(IP)中的分布,荧光定量PCR及Western blot检测IP区域脑组织中PTEN的表达水平,并与正常大鼠及MCAO组大鼠进行对比。结果MSCs-EXO治疗组的神经功能恢复高于MCAO组,差异有统计学意义(P<0.05)。免疫荧光染色显示标记外泌体可以进入IP区域神经细胞,荧光定量PCR及Western blot检测显示MSCs-EXO治疗组及MCAO组中PTEN水平均较正常升高,但MSCs-EXO治疗组的PTEN水平低于MCAO组,差异有统计学意义(P<0.05)。结论MSCs-EXO能够促进缺血性脑卒中大鼠的神经功能恢复,这可能与其下调IP区域PTEN表达水平相关。

Effect of Hypertension on Hearing Function,LDH and ChE of the Cochlea in Older Rats

The relationship between the hypertension and the aging process of hearing organ was investigated Twenty Wistar 3-month old rats and 20 Wistar 12-month old rats, 20 spontaneously hypertensive rat stroke-prone (SHRSP) 3-month old rats and 20 SHRSP 12-month old rats free of middle ear infections as observed under otomicroscopy, with normal tympanic membrane and auricle reflex, were selected to be divided into two experimental groups and two control groups respectively The tail artery blood pressure was measured non-invasively The threshold of auditory brainstem response (ABR) was measured by Spirit TM evoked potential meter The LDH and ChE staining in the inner ear was performed and the optical density was analyzed by the HPIAS analysis system The results showed that there was no difference in the ABR thresholds, the activities of LDH and ChE between Wistar 3-month old group and SHRSP 3-month old group ( P >0 05) The mean value of ABR threshold and the activities of LDH and ChE in the Wistar 12-month old group at relevant sections were significantly greater than those in the two 3-month old groups ( P< 0 05), whereas the mean value of ABR threshold and the activities of LDH and ChE in the SHRSP 12-month old group at relevant sections were significantly higher than those in the 3-month old control group ( P< 0 01) It was concluded that presbycusis existed in the Wistar 12-month old group rats The glycogenosis and the abnormal secretion of neural transmitter were discerned after hypertension All the above factors may worsen the aging of the hearing system

石墨相氮化碳二维纳米片载洋川芎内酯Ⅰ应用于缺血性脑卒中大鼠的治疗研究

目的:探讨石墨相氮化碳(g-C_(3)N_(4))二维纳米片负载洋川芎内酯I(SEI)对缺血性脑卒中大鼠的治疗作用。方法:利用三聚氰胺通过热相反应生成层状g-C_(3)N_(4),热剥酸剥后得到薄层g-C_(3)N_(4)纳米片并进行表征;将SEI负载到g-C_(3)N_(4)纳米片上,通过紫外可见吸收光谱测定上清中的SEI,计算g-C_(3)N_(4)负载SEI质量比,测定SEI-g-C_(3)N_(4)复合纳米片在1 h、3 h、6 h、12 h、24 h和48 h的药物释放情况;SD大鼠大脑中动脉闭塞(MCAO)造模前48 h通过脑立体定位注射SEI-g-C_(3)N_(4)复合纳米片,造模后24 h进行神经行为学评分,评分结束后取材分别进行TTC染色、TUNEL染色和HE染色。结果:通过表征实验,制备的g-C_(3)N_(4)纳米片尺寸小(约100 nm)、比表面积大、分散性好、表面带正电荷(33.3 mV);紫外可见吸收光谱测定结果显示,g-C_(3)N_(4)已成功负载SEI,且SEI/g-C_(3)N_(4)质量比为15.06;药物释放结果显示,24 h时SEI的释放率接近50%;与sham组相比,MCAO组神经功能缺失评分显著升高(P<0.0001),表明造模成功;与MCAO组相比,MCAO+SEI组神经功能缺失评分减少(P>0.05),MCAO+SEI-g-C_(3)N_(4)组神经功能缺失评分减少(P<0.001);与MCAO+SEI组相比,MCAO+SEI-g-C_(3)N_(4)组神经功能缺失评分减少(P<0.01);TTC染色结果表明,与sham组相比,MCAO组的脑梗死面积显著增加(P<0.0001);与MCAO组相比,MCAO+SEI组梗死面积减少(P<0.0001),MCAO+SEI-g-C_(3)N_(4)组脑梗死面积显著减少(P<0.0001);与MCAO+SEI组相比,MCAO+SEI-g-C_(3)N_(4)组脑梗死面积减少(P<0.001);TUNEL染色结果表明,与sham组相比,MCAO组的凋亡率升高(P<0.0001),表明造模成功;与sham组相比,MCAO+SEI-g-C_(3)N_(4)组凋亡率升高(P>0.05);与MCAO组相比,MCAO+SEI-g-C_(3)N_(4)组凋亡率减少(P<0.001);体内生物安全性实验结果表明,与sham组相比,SEI组、SEI-g-C_(3)N_(4)组大鼠体重无统计学差异,且皮层脑组织结构和细胞形态无明显病理性变化。结论:成功制备了生物安全性较好的SEI-g-C_(3)N_(4)复合纳米片,且其能够减少MCAO大鼠的脑梗死面积,抑制细胞凋亡,减轻脑组织病理性变化,并且能改善大鼠的神经行为功能,表明SEI-g-C_(3)N_(4)复合纳米片可用于治疗缺血性脑卒中大鼠。

G-CSF介导的小胶质细胞自噬活性降低在大鼠酒精使用障碍脑卒中中的脑保护作用研究

目的探讨大鼠酒精使用障碍(AUD)脑卒中后粒细胞集落刺激因子(G-CSF)治疗对小胶质细胞自噬活性的影响及其神经保护作用。方法将54只SD雄性大鼠按照随机数字表法分为AUD组、AUD+大脑中动脉栓塞(MCAO)组、AUD+MCAO+G-CSF组,每组各18只。AUD组用20%酒精双瓶法构建AUD大鼠模型,AUD+MCAO组、AUD+MCAO+G-CSF组均在AUD模型基础上制作MCAO局部脑缺血模型,AUD+MCAO+G-CSF组大鼠缺血再灌注损伤1 h后腹腔注射G-CSF 50μg/kg治疗。每天记录所有大鼠的酒精摄入量及偏好。观察各组大鼠脑缺血再灌注损伤24 h后检测脑梗死面积和神经功能评分。采用免疫荧光染色及蛋白质印迹法检测各组大鼠缺血侧大脑皮层小胶质细胞特异性标志物TMEM119、自噬标记物LC-3的表达水平。结果到末次饮酒28 d时酒精摄入量已达到稳定水平,酒精偏好明显增加。与AUD组比较,AUD+MCAO组的脑梗死面积显著升高,神经功能评分显著减少,差异均有统计学意义(P<0.05);与AUD+MCAO组比较,AUD+MCAO+G-CSF组的脑梗死面积明显减少,神经功能评分明显升高,差异均有统计学意义(P<0.05)。免疫荧光染色结果显示:与AUD组比较,AUD+MCAO组TMEM119和LC-3蛋白表达荧光强度明显增强,差异均有统计学意义(P<0.05);与AUD+MCAO组比较,AUD+MCAO+G-CSF组TMEM119和LC-3蛋白表达荧光强度均明显减弱,差异均有统计学意义(P<0.05)。此外,免疫荧光显示TMEM119和LC-3二者有明显共定位。蛋白质印迹法结果显示,TMEM119和LC-3在AUD组表达微弱,与AUD组比较,AUD+MCAO组TMEM119和LC-3蛋白表达均明显升高,差异均有统计学意义(P<0.05);与AUD+MCAO组比较,AUD+MCAO+G-CSF组TMEM119和LC-3蛋白表达明显降低,差异均有统计学意义(P<0.05)。结论G-CSF通过降低小胶质细胞的自噬活性,在AUD脑损伤中发挥重要的脑保护作用。

三七皂苷R1对脑缺血再灌注诱导焦亡的影响

目的:研究三七皂苷R1对大鼠脑缺血再灌注损伤的保护作用及其可能机制。方法:将70只SD大鼠随机分为对照组、假手术组、模型组、三七皂苷R1低剂量组、三七皂苷R1中剂量组、三七皂苷R1高剂量组及依达拉奉组,每组10只。三七皂苷R1低、中、高剂量组大鼠分别灌胃低[25 mg/(kg·d)]、中[50 mg/(kg·d)]、高[100 mg/(kg·d)]剂量三七皂苷R1混悬液,依达拉奉组大鼠腹腔注射依达拉奉[3 mg/(kg·d)]。连续给药7 d后,除对照组和假手术组外,其余各组大鼠构建大脑中动脉阻断(MCAO)模型,再灌注24 h后取材。采用Zea Longa法进行神经功能学评价;测定脑组织含水量;采用苏木精-伊红(HE)染色评价脑组织病理变化;采用酶联免疫吸附法(ELISA)法测定脑组织IL-18和IL-1β的含量;采用蛋白质印迹法检测脑组织NLRP3、GSDMD和Caspase-1蛋白的表达。结果:模型组大鼠神经功能损伤评分、脑含水量高于假手术组(P<0.01);模型组大鼠脑组织中IL-18和IL-1β的含量及NLRP3、Caspase-1、GSDMD蛋白相对表达量高于假手术组(P<0.01)。三七皂苷R1中、高剂量组及依达拉奉组大鼠神经功能损伤评分、脑组织含水量均低于模型组(P<0.05或P<0.01);三七皂苷R1中、高剂量组及依达拉奉组大鼠脑组织中IL-18和IL-1β水平及NLRP3、Caspase-1、GSDMD蛋白相对表达量均低于模型组(P<0.05或P<0.01)。结论:三七皂苷R1对大鼠脑缺血再灌注损伤有抑制作用,其作用机制可能与抑制缺血再灌注引起的焦亡有关。

基于数据非依赖型采集蛋白质组学分析劳力性热射病大鼠血浆蛋白的变化

目的采用数据非依赖型采集(DIA)蛋白质组学技术分析劳力性热射病(EHS)大鼠血浆蛋白表达的变化。方法取SPF级雄性SD大鼠10只,随机分为正常对照组(CON组,n=5)和EHS组(n=5),EHS组造模前1周完成温度遥测胶囊植入术,术毕恢复7 d后大鼠在人工气候舱内(温度40℃,相对湿度70%)跑步,监测核心温度达到42.5℃时视为发生EHS。停止跑步后采血进行DIA定量蛋白质组学分析。结果以表达倍数>1.5倍且P<0.05为筛选标准,共筛选出625个上调差异表达蛋白(DEPs)和8个下调DEPs。亚细胞定位注释表明,DEPs主要位于细胞外和细胞质;基因本体论(GO)注释显示,DEPs分子主要功能为蛋白质结合;京都基因与基因组百科全书(KEGG)注释显示,DEPs主要参与免疫反应、能量代谢等信号通路;同源蛋白簇(COG)注释显示,DEPs主要发挥翻译后修饰、蛋白质周转和伴侣功能。蛋白结构域富集分析显示,DEPs结构域主要集中在免疫球蛋白结构域、血小板反应蛋白1型结构域和补体Clr样EGF样结构域;GO富集分析显示,DEPs主要参与血液凝固和纤维蛋白凝块形成、纤溶酶原激活、急性炎症反应的调节等过程;KEGG富集分析显示,DEPs主要参与补体和凝血级联、免疫和细胞黏附分子等信号通路;Reactome通路富集分析显示,DEPs主要参与先天免疫系统、中性粒细胞脱颗粒和血小板活化等信号通路;蛋白互作网络分析发现,参与补体和凝血级联通路的蛋白网络互作较多,且以上调蛋白Fgg、Plg和Serpinc1为主。结论EHS明显改变大鼠血浆中蛋白表达谱,主要涉及免疫系统异常激活、炎症反应失控和凝血功能紊乱的信号通路。

补阳还五汤与黄芪甲苷治疗缺血性脑卒中大鼠的疗效比较研究

目的:比较补阳还五汤与黄芪甲苷治疗大鼠缺血性脑卒中的疗效。方法:将50只SD大鼠随机分组,分为假手术组(Sham组)、模型组(MCAO组)、补阳还五汤组(BYHWD组)、黄芪甲苷组(AS-IV组)与血塞通组(XueSaiTong组),每组各10只。建立大鼠大脑中动脉闭塞(middle cerebral arterial occlusion,MCAO)模型,利用Zea Longa法评估神经功能缺损程度,TTC染色检测脑梗死体积,HE染色观察神经细胞病理形态学改变,尼氏染色观察尼氏体变化,免疫组化染色、免疫荧光染色观察和比较神经元特异性核蛋白NeuN表达。结果:与MCAO组相比,BYHWD组、AS-IV组和XueSaiTong组大鼠神经功能缺损症状均减轻(P<0.05),脑梗死体积缩小(P<0.05),神经细胞形态规则,尼氏体数量增多(P<0.05),NeuN蛋白表达升高(P<0.05);与AS-IV组相比,BYHWD组神经功能缺损症状有所减轻,但差异无统计学意义(P>0.05),其余检测结果以BYHWD组疗效较好(P<0.05)。结论:补阳还五汤、黄芪甲苷二者均可起到减轻MCAO大鼠神经功能缺损的效果,发挥神经保护作用;其中补阳还五汤治疗效果更好。

电针神庭、百会穴通过ARC/GluR2/NMDAR2B调节海马突触可塑性改善MCAO/R大鼠学习记忆的机制研究

目的观察电针神庭、百会穴对大脑中动脉闭塞再灌注(MCAO/R)大鼠学习记忆功能改善的作用机制。方法线栓法制备MCAO/R大鼠模型。24只雄性SD大鼠随机分为模型组(n=6)、电针组(n=6)、非穴组(n=6)和假手术组(n=6)。电针组大鼠选取百会、神庭穴,非穴组选取双侧胁下非经非穴,共电针7 d。ZeaLonga评分法对各组大鼠进行神经功能缺损评分,新物体识别评估大鼠的学习记忆能力,小动物磁共振T2WI系列扫描梗死面积,HE染色观察缺血侧海马病理形态,波谱(1HMRS)比较各组海马区N-乙酰天冬氨酸(NAA)、肌酸(Cr)和谷氨酸(Glu)代谢物含量,Western blotting检测缺血侧海马ARC/GluR2/NMDAR2B的表达情况。结果干预7 d后,与模型组及非穴组比较,电针组大鼠神经功能缺损评分显著降低(P<0.05),电针组大鼠新物体识别指数较模型及非穴组升高(P<0.05)。磁共振T2WI显示电针组的梗死面积较模型组、非穴组明显减小(P<0.05),波谱显示电针组较模型和非穴组海马区NAA/Cr比值明显增高(P<0.001),GLU/Cr降低(P<0.01)。Western blotting结果表明电针组大鼠缺血侧海马中NMDAR2B含量明显低于模型组和非穴组(P<0.01),ARC及GluR2含量高于模型及非穴组(P<0.05)。结论电针神庭、百会穴能够改善MCAO/R大鼠的神经缺损情况,提高学习记忆能力,降低缺血侧梗死面积,改善病理形态,提高神经元兴奋性,降低膜后谷氨酸累积,其机制可能与促进MCAO/R大鼠海马区ARC、GluR2,抑制NMDAR2B的表达,进而改善卒中后海马突触可塑性损伤有关。

巨刺阳陵泉穴对MCAO模型大鼠运动功能作用机制研究

目的:观察巨刺阳陵泉穴对大脑中动脉栓塞(MCAO)模型大鼠运动功能障碍的疗效和对胼胝体髓鞘碱性蛋白(MBP)的影响,探讨巨刺阳陵泉穴改善脑梗死运动障碍的机制。方法:将68只雄性SD大鼠随机分为假手术组、模型组、巨刺组和非经非穴组,每组17只。除假手术组外,其余三组均用线栓法制备右侧MCAO模型,术后第2天开始干预,巨刺组电针刺激右侧阳陵泉,非经非穴组电针刺激双侧胁下非经非穴位置,每天1次,每次20 min,连续14 d。测定大鼠抓力、神经功能缺损得分;2,3,5-三苯基氯化四氮唑(TTC)染色计算脑梗死体积百分比,苏木精-伊红染色法(HE)观察胼胝体组织形态,免疫组化、酶联免疫吸附测定(ELISA)法、蛋白质印迹(WB)法、反转录聚合酶链反应(RT-PCR)法分别检测右脑胼胝体MBP蛋白及mRNA表达水平。结果:与假手术组相比,模型组大鼠抓力下降,神经功能缺损得分增加,脑梗死体积百分比增加,胼胝体髓鞘结构崩解,右脑胼胝体MBP蛋白及mRNA表达水平降低,差异均有统计学意义(P<0.05)。与模型组、非经非穴组比,巨刺组大鼠抓力增大,神经功能缺损得分降低,脑梗死体积百分比降低,髓鞘结构较为完整,右脑胼胝体MBP蛋白及mRNA表达水平升高,差异均有统计学意义(P<0.05)。结论:巨刺阳陵泉穴可能通过提高胼胝体MBP蛋白表达水平促进MCAO大鼠运动功能康复。