Effects of acute treatment with dexamethasone on hemodynamic and histopathological changes in rats

We assessed the time-dependent effects of intraperitoneal (i.p.) and intravenous (i.v.) application of dexamethasone (Dexa) on the mean arterial blood pressure (MAP), heart rate (HR) and total blood volume (TBV). We evaluated also the relation between the effects and immunoreactivities of transforming growth factor-beta (TGF-β), epithelial nitric oxide synthase (eNOS), interleukin-1 beta (IL1-β) and vascular endothelial growth factor (VEGF) in rat brain, lung and kidney tissues. Rats were anesthetized and while still breathing spontaneously, a tracheotomy and femoral vein and artery catheterizations were performed. To determine TBV using the hemodilution method, 2 ml albumin-electrolyte solutions were applied by i.v. injection. Group 1 (control group) received a 1 ml bolus injection of physiologic saline, Group 2 received 15 mg/kg and Group 3 received 75 mg/kg Dexa i.p. The hematocrit was measured at 10, 20, 60 and 120 min. For each animal, the values of MAP, HR and TBV were measured within 2 h. For immunohistochemical evaluation, anti-TGF-β, anti-eNOS, anti-IL1-β and anti-VEGF primary antibodies were tested using the avidin-biotin-peroxidase method. TBV was decreased in Group 1 and the increase in MAP was statistically significant. HR values increased slightly. None of the values changed significantly in Group 2. Although TBV was unchanged in Group 3, the decrease in MAP was statistically significant. HR values increased, but the increase was not statistically significant. Mild IL1-β immunoreactivity and moderate TGF-β, eNOS and VEGF immunoreactivities were observed in the brain, lung and kidney samples in Group 1. Increased eNOS immunoreactivity in the kidney samples were observed in Group 2. eNOS immunoreactivity was as strong in the brain and the kidney samples in Group 3. Decreased VEGF immunoreactivity was observed in the lung and kidney tissues in Group 3. Significantly decreased TGF-β immunoreactivity was observed in all tissue samples in Group 3. The decreased MAP values in Group 3 differed from those in Groups 1 and 2. Despite increased eNOS immunoreactivity, especially in brain and kidney, the decrease in VEGF immunoreactivity in Group 3, especially lung and kidney, were consistent with a drop in blood pressure.     

Effects of acute treatment with dexamethasone on hemodynamic and histopathological changes in rats

Abstract

We assessed the time-dependent effects of intraperitoneal (i.p.) and intravenous (i.v.) application of dexamethasone (Dexa) on the mean arterial blood pressure (MAP), heart rate (HR) and total blood volume (TBV). We evaluated also the relation between the effects and immunoreactivities of transforming growth factor-beta (TGF-β), epithelial nitric oxide synthase (eNOS), interleukin-1 beta (IL1-β) and vascular endothelial growth factor (VEGF) in rat brain, lung and kidney tissues. Rats were anesthetized and while still breathing spontaneously, a tracheotomy and femoral vein and artery catheterizations were performed. To determine TBV using the hemodilution method, 2 ml albumin-electrolyte solutions were applied by i.v. injection. Group 1 (control group) received a 1 ml bolus injection of physiologic saline, Group 2 received 15 mg/kg and Group 3 received 75 mg/kg Dexa i.p. The hematocrit was measured at 10, 20, 60 and 120 min. For each animal, the values of MAP, HR and TBV were measured within 2 h. For immunohistochemical evaluation, anti-TGF-β, anti-eNOS, anti-IL1-β and anti-VEGF primary antibodies were tested using the avidin-biotin-peroxidase method. TBV was decreased in Group 1 and the increase in MAP was statistically significant. HR values increased slightly. None of the values changed significantly in Group 2. Although TBV was unchanged in Group 3, the decrease in MAP was statistically significant. HR values increased, but the increase was not statistically significant. Mild IL1-β immunoreactivity and moderate TGF-β, eNOS and VEGF immunoreactivities were observed in the brain, lung and kidney samples in Group 1. Increased eNOS immunoreactivity in the kidney samples were observed in Group 2. eNOS immunoreactivity was as strong in the brain and the kidney samples in Group 3. Decreased VEGF immunoreactivity was observed in the lung and kidney tissues in Group 3. Significantly decreased TGF-β immunoreactivity was observed in all tissue samples in Group 3. The decreased MAP values in Group 3 differed from those in Groups 1 and 2. Despite increased eNOS immunoreactivity, especially in brain and kidney, the decrease in VEGF immunoreactivity in Group 3, especially lung and kidney, were consistent with a drop in blood pressure.     

Disruption of COX-2 and eNOS does not confer protection from cardiovascular failure in lipopolysaccharide-treated conscious mice and isolated vascular rings

It was hypothesized that a serial stimulation of vascular cyclooxygenase-2 (COX-2) with subsequent activation of endothelial nitric oxide synthase (eNOS) is responsible for decrease in blood pressure, cardiac performance, and vascular reactivity in endotoxemia caused by LPS. The hypothesis was tested in catheterized, conscious, freely moving, wild-type mice and mice (C57BL/6J background) with targeted deletion of COX-2 and eNOS that were given an intravenous LPS bolus (2 mg/kg, 055:B5). In vitro studies were performed on murine aorta rings. LPS caused a concomitant decrease in mean arterial blood pressure (MAP) and heart rate (HR) that was significant after 3 h and was sustained throughout the experiment (8 h). The LPS-induced changes in MAP and HR were not different from control in COX-2(-/-) and eNOS(-/-) mice. A prostacyclin receptor antagonist (BR5064) blocked the hypotensive effect of a prostacyclin agonist (beraprost), but did not attenuate the LPS-induced decrease in MAP and HR. LPS decreased eNOS and neuronal NOS mRNA abundances in several organs, while inducible NOS mRNA was enhanced. In aortic rings, LPS suppressed α(1)-adrenoceptor-mediated vascular tone. Inhibition of COX-2 activity (NS 398), disruption of COX-2, endothelium removal, or eNOS deletion (eNOS(-/-)) did not improve vascular reactivity after LPS, while the NO synthase blockers 1400W and N(G)-nitro-l-arginine methyl ester prevented loss of tone. COX-2 and eNOS activities are not necessary for LPS-induced decreases in blood pressure, heart rate, and vascular reactivity. Inducible NOS activity appears crucial. COX-2 and eNOS are not obvious therapeutic targets for cardiovascular rescue during gram-negative endotoxemic shock.     

Editor's note

Dibutryl (DB) adenosine 3′,5′-cyclic monophosphate (cAMP) is an important modulator of physiological functions. To determine the protective effects of DBcAMP on heart tissue, we evaluated changes in immunoreactivity of endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS) and transforming growth factor-beta (TGF-β) in left cervical vagotomized rats treated with DBcAMP. Male rats were divided into four groups. In Group 1, animals were subjected to a left cervical vagotomy. Group 2 received a 1 ml bolus injection of 15 ml/kg DBcAMP in addition to the left vagotomy. DBcAMP alone was given to Group 3 and Group 4 was the control group. For each animal, mean arterial pressure (MAP) and heart rate (HR) were measured. For indirect immunohistochemistry, anti-eNOS, anti-iNOS, and anti-TGF-β primary antibodies were used. In Group 1, MAP and HR values decreased slightly. In Groups 2 and 3, DBcAMP induced a statistically significant drop in HR and MAP. In Group 1, strong eNOS, iNOS, and TGF-β immunoreactivities were observed. Immunostaining intensities decreased in Groups 2 and 3. The results of the study reported here suggest that increased immunoreactivities of eNOS, iNOS, and TGF-β might contribute to the effects on the heart tissue after left vagotomy and imply that DBcAMP acts on heart tissue via nitric oxide.     

右美托咪定对腹腔镜子宫切除术患者血流动力学及应激反应的影响

目的:探讨右美托咪定(Dex)对腹腔镜子宫切除术患者血流动力学及应激反应的影响。方法:选择2012年7月到2014年7月在我院行腹腔镜子宫切除术的36例患者,随机分为实验组和对照组各18例。实验组静脉注射Dex 1μg/kg直到手术结束,对照组同法给予生理盐水。于麻醉前15 min(T0)、插管后5 min(T1)、气腹后20 min(T2)、术后立刻(T3)和术后24 h(T4)四个时间点,分别监测其平均动脉压(MAP)、心率(HR),并测定血浆皮质醇(Cor)、去甲肾上腺素(NE)和白细胞介素6(IL-6)水平。结果:T0时两组患者的MAP和HR比较,无显著性差异(P0.05),对照组T1、T2、T3时明显升高(P0.05),实验组轻微升高,两组相比差异有显著性(P0.05)。T4时两组患者的MAP和HR均恢复至正常水平。T0时两组Cor、NE和IL-6比较,无显著性差异(P0.05),对照组T2、T3、T4时明显升高(P0.05),实验组轻微升高,两组相比差异有显著性(P0.05)。T4时除NE,其他指标均达到峰值。结论:Dex能维持围术期患者血流动力学稳定,降低术中的应激反应。     

以每搏量变异度为指导的目标导向液体治疗对肝癌手术患者血流动力学、应激反应及肝肾功能的影响

摘要 目的：观察以每搏量变异度（SVV）为指导的目标导向液体治疗对肝癌手术患者血流动力学、应激反应及肝肾功能的影响。方法：选择2019年4月~2022年1月期间我院收治的肝癌手术患者98例,根据随机数字表法分为对照组[控制性低中心静脉压（CLCVP）指导的目标导向液体治疗,49例]和研究组（SVV为指导的目标导向液体治疗,49例）。对比两组临床指标、血流动力学、肝肾功能指标、应激反应、并发症发生率。结果：研究组的输液量、围术期失血量、围术期输血量少于对照组（P<0.05）。两组术后1d、术后3d谷草转氨酶（AST）、总胆红素（DBIL）、谷丙转氨酶（ALT）、血尿素氮（BUN）、肌酐（Cr）均升高后下降,且研究组的变化程度小于对照组（P<0.05）。两组手术开始（T1）~术毕（T4）时间点心率（HR）、平均动脉压（MAP）下降后升高（P<0.05）,T1~T4时间点研究组HR、MAP高于对照组（P<0.05）。两组术后1 d、术后3 d皮质醇（Cor）、前列腺素E₂（PGE₂）均升高后下降,且研究组的变化程度小于对照组（P<0.05）。两组并发症发生率对比无差异（P>0.05）。结论：肝癌手术患者选用SVV为指导的目标导向液体治疗,可维持血流动力学稳定,减轻应激反应及肝肾功能损伤。     

Cyclooxygenase-2 Immunoreactivity and Protein Level in the Gerbil Hippocampus During Normal Aging

Cyclooxygenases-2 (COX-2) is not only related to inflammation but also plays critical roles in brain development and synaptic signaling. In the present study, we investigated age-related changes in COX-2 immunoreactivity and protein levels in the gerbil hippocampus. In the hippocampal CA1 region (CA1) and dentate gyrus (DG), weak COX-2 immunoreactivity was observed at postnatal month 1 (PM 1), and COX-2 immunoreactivity was markedly increased at PM 18 and 24. In the CA2/3, COX-2 immunoreactivity was strong at PM 1. COX-2 immunoreactivities in the PM 3, 6 and 12 groups were decreased compared to that in the PM 1 group, and it was increased at PM 18 and 24. In addition, age-related changes in COX-2 levels were similar with immunohistochemical results in the CA2/3. These results suggest that COX-2 immunoreactivity and levels were high in the hippocampus of aged gerbils.     

帕瑞昔布钠复合舒芬太尼对甲状腺手术患者术后镇痛镇静效果、血流动力学及炎症反应的影响

目的:探讨帕瑞昔布钠复合舒芬太尼对甲状腺手术患者术后镇痛镇静效果、血流动力学及炎症反应的影响.方法:选择2018年6月～2019年6月期间100例在我院择期行甲状腺手术患者,根据随机数字表法分为对照组(n=50,术后镇痛予以舒芬太尼)和研究组(n=50,术后镇痛予以帕瑞昔布钠复合舒芬太尼),比较两组患者术后镇痛镇静效果...     

Acute angiotensin-converting enzyme inhibition evokes bradykinin-induced sympathetic activation in diabetic rats

We have previously shown that acute intravenous injection of the angiotensin-converting enzyme (ACE) inhibitor enalapril in diabetic rats evokes a baroreflex-independent sympathoexcitatory effect that does not occur with angiotensin receptor blockade alone. As ACE inhibition also blocks bradykinin degradation, we sought to determine whether bradykinin mediated this effect. Experiments were performed in conscious male Sprague-Dawley rats, chronically instrumented to measure mean arterial pressure (MAP), heart rate (HR), and renal sympathetic nerve activity (RSNA), 2 wk after streptozotocin (55 mg/kg iv, diabetic, n = 11) or citrate vehicle (normal, n = 10). Enalapril (2.5 mg/kg iv) decreased MAP in normal rats (-15 +/- 3 mmHg), while a smaller response (-4 +/- 1 mmHg) occurred in diabetic rats. Despite these different depressor responses to enalapril, HR (+44 +/- 8 vs. +26 +/- 7 bpm) and RSNA (+90 +/- 21 vs +71 +/- 8% baseline) increased similarly between the groups (P > or = 0.22 for both). Pretreatment with the bradykinin B2 receptor antagonist Hoe 140 (10 microg/kg bolus followed by 0.8.mug(-1)kg.min(-1) infusion) attenuated the decrease in MAP observed with enalapril in normal rats but had no effect in diabetic rats. Moreover, the normal group had smaller HR and RSNA responses (HR: +13 +/- 8 bpm; RSNA: +32 +/- 13% baseline) that were abolished in the diabetic group (HR: -4 +/- 5 bpm; RSNA: -5 +/- 9% baseline; P < 0.05 vs. preenalapril values). Additionally, bradykinin (20 microg/kg iv) evoked a larger, more prolonged sympathoexcitatory effect in diabetic compared with normal rats that was further potentiated after treatment with enalapril. We conclude that enhanced bradykinin signaling mediates the baroreflex-independent sympathoexcitatory effect of enalapril in diabetic rats.     

全凭静脉麻醉复合椎旁神经阻滞对胸腔镜下肺病损切除术患者应激反应、血流动力学及术后镇痛的影响

目的:研究全凭静脉麻醉复合胸椎旁神经阻滞(TPVB)对胸腔镜下肺病损切除术患者应激反应、血流动力学及术后镇痛的影响。方法:选择2016年6月至2017年12月在我院行胸腔镜下肺病损切除术的80例患者为研究对象。采用简单随机抽样方法,分为对照组(n=40)和观察组(n=40)。对照组行单纯全身麻醉,观察组在超声引导下行TPVB复合全身麻醉。比较两组麻醉前、术毕、术后24 h的血糖、肾上腺素(E)、去甲肾上腺素(NE)及多巴胺(DA)的浓度,以及两组在麻醉时、手术开始时、手术开始后0.5 h、手术开始后1 h、术毕时的平均动脉压(MAP)和心率(HR),同时比较两组术后2 h、6 h、12 h、24 h静息及活动时的视觉模拟评分(VAS)及相关并发症的发生率。结果:两组患者在麻醉前及术毕的各应激反应指标比较无差异(P0.05),而术后24 h比较,观察组低于对照组(P0.05);两组患者麻醉时的MAP、HR比较无差异(P0.05),除手术开始后1 h和术毕的HR外,观察组各时间的MAP、HR均显著低于对照组(P0.05);除静息时24 h外,观察组各时间静息时和活动时的VAS评分均低于对照组(P0.05);两组患者术后各并发症的发生率比较无统计学差异(P0.05)。结论:全凭静脉麻醉复合TPVB在胸腔镜下肺病损切除术中应激反应小,对血流动力学的波动影响小,术后镇痛效果良好,且安全有效。     

肠淋巴液引流对失血性休克小鼠心肌组织ACE/ACE2的作用

目的：观察失血性休克后小鼠心肌组织血管紧张素转换酶（ACE）/ACE2平衡的变化及肠淋巴液引流（PHSML）的作用。方法：BALB/c雄性小鼠24只,随机分为对照组、假手术组、休克组、休克+引流组（n=6）。建立失血性休克模型,行液体复苏;休克+引流组液体复苏后,引流肠淋巴液。在液体复苏后6 h或假手术组相应时间点、对照组于麻醉后,留取心肌组织,qRT-PCR法检测ACE、ACE2、血管紧张素Ⅱ （Ang Ⅱ）1型受体（AT1R）、Mas相关G蛋白偶联受体（Mas1R）的mRNA表达,ELISA方法检测Ang Ⅱ和Ang （1-7）含量。结果：休克组小鼠心肌组织ACE与AT1R mRNA表达、Ang Ⅱ水平均显著高于对照组与假手术组,ACE2与Mas1R mRNA表达显著低于对照组与假手术组、Ang （1-7）含量显著低于对照组,ACE/ACE2、Ang Ⅱ/Ang （1-7）、AT1R/Mas1R显著高于对照组与假手术组;PHSML引流显著抑制了失血性休克对这些指标的作用。结论：失血性休克上调心肌ACE-Ang Ⅱ-AT1R轴、下调ACE2-Ang （1-7）-Mas1R轴表达,引起ACE/ACE2失衡;PHSML引流下调ACE-Ang Ⅱ-AT1R轴、上调ACE2-Ang （1-7）-Mas1R轴表达,在一定程度上维持了ACE/ACE2平衡。     

Excessive Zinc Intake Increases Systemic Blood Pressure and Reduces Renal Blood Flow via Kidney Angiotensin II in Rats

This study investigated the effects of excess zinc intake on the mean arterial pressure (MAP), renal blood flow (RBF), inulin clearance (IC), serum zinc level, serum angiotensin-converting enzyme (ACE) activity, and kidney angiotensin II (AT II) levels in rats. Experiments were performed on male Sprague?CDawley rats maintained for 4?weeks on a diet containing either 5?mg/100?g (control group), 50?mg/100?g (Zn50 group), or 200?mg/100?g (Zn200 group) zinc carbonate. Serum zinc levels significantly increased to 126.5?% in the Zn50 group and 198.1?% in the Zn200 group compared with controls. MAP significantly increased to 107.8?% in the Zn50 group and 114.5?% in the Zn200 group again compared with controls. Although the difference in serum ACE activity was independent of the serum zinc levels, the kidney AT II levels increased significantly to 137.2?% in the Zn50 group and 174.4?% in the Zn200 group compared with the controls. RBF was decreased significantly to 74.4?% in the Zn50 group and 69.7?% in the Zn200 group compared with the controls. IC values were significantly decreased to 69.6?% in the Zn50 group and 52.7?% in the Zn200 group as compared with control levels. Combined together, these results show that excessive Zn intake reduced IC and RBF and increased MAP and kidney AT II levels, suggesting that excessive Zn intake reduces renal function.     

布托啡诺预处理联合超声引导下胸椎旁神经阻滞麻醉对胸腔镜下肺癌根治术患者镇痛效果及应激反应的影响

摘要 目的：探究布托啡诺预处理联合超声引导下胸椎旁神经阻滞麻醉（TPVB）对胸腔镜下肺癌根治术患者镇痛效果及应激反应的影响。方法：选取2021年5月至2022年6月我院60例肺癌患者,采用随机数字表法分为观察组（n=30）和对照组（n=30）。两组均给予静脉麻醉,术后均采用静脉自控镇痛（PCIA）,观察组术前在超声引导下行TPVB,并给予布托啡诺预处理。比较两组血流动力学、麻醉效果、术后疼痛情况、应激反应、不良反应发生情况。结果：与T₀时刻比较,两组T₁时刻心率（HR）、平均动脉压（MAP）均下降（P<0.05）;与T₁时刻比较,两组T₂时刻HR、MAP均升高（P<0.05）;与对照组比较,观察组T₂、T₃时刻HR、MAP均较低（P<0.05）。观察组丙泊酚、瑞芬太尼用量、拔管时间、PCIA使用次数较对照组更低、更短、更少（P<0.05）。术后8 h、12 h、24 h,观察组静息时、咳嗽时疼痛程度均低于对照组（P<0.05）。术后,两组肾上腺素（E）、皮质醇（Cor）、促肾上腺皮质激素（ACTH）均升高（P<0.05）,但观察组E、Cor、ACTH均低于对照组（P<0.05）。两组不良反应总发生率比较无明显差异（P＞0.05）。结论：胸腔镜下肺癌根治术患者使用布托啡诺预处理联合超声引导下TPVB能控制血流动力学与阿片类药物总用量,缩短拔管时间,还能减轻术后疼痛与应激反应。     

Accumulation of microtubule-associated proteins in the hippocampal neurons of seizure-sensitive gerbils

We have carried out a chronological and comparative analysis of microtubule-associated protein 1A (MAP1A) and microtubule-associated protein 2 (MAP2) immunoreactivities in the hippocampi of seizure-resistant (SR) and seizure-sensitive (SS) gerbils. These animals represent excellent genetic models of epilepsy associated with different sequelae of spontaneous seizures. Both MAP1A and MAP2 immunoreactivities were detected in the granule cell layer and in the hilar neurons of SR gerbils. In contrast with the SR gerbils, some neurons containing MAPs immunoreactivities were scattered in the molecular layer of the dentate gyrus as well as being concentrated in the hilar neurons in the SS gerbils. An increase in MAP1A immunoreactivity was evident in the perikarya of the dentate gyrus at 30 min postictal, whereas MAP2 immunoreactivity decreased. MAP1A immunoreactivity in the hilar neurons declined significantly by 3 h postictal, whereas MAP2 immunoreactivity increased. These results suggest that the immunoreactivity of MAPs in the hippocampal complex differs between SR and SS gerbils, and that this difference may be the results of seizure activity.     

限制性补液复合去甲肾上腺素对脓毒性休克患者血流动力学及氧代谢的影响

目的:探讨限制性补液复合去甲肾上腺素对脓毒性休克患者血流动力学及氧代谢的影响。方法:将62例脓毒性休克患者按照液体复苏策略随机分为限制性液体复苏(治疗组)和常规液体复苏(对照组),每组各31例。观察和比较复苏前后血流动力学指标、氧代谢指标的变化,记录两组低血压、弥散性血管内凝血(DIC)、多器官功能障碍综合征(MODS)、急性呼吸窘迫综合症(ARDS)的发生率及2周病死率。结果:治疗后1 h、3 h、6 h,两组患者CVP、MAP明显升高,HR明显下降(P0.05);治疗后3 h、6 h,治疗组MAP明显低于对照组(P0.05),而两组HR、CVP比较差异均无统计学意义(P0.05)。治疗后1 h、3 h、6 h,两组患者PaCO_2、PaO_2、SaO_2、PaO_2/Fi O_2均不同程度改善,治疗组治疗后3 h、6 h PaO_2、PaO_2/Fi O_2明显高于对照组(P0.05)。治疗后3 d,治疗组MODS的发生率较对照组显著降低(P0.05),而两组低血压、ARDS、DIC及2周病死率均无显著性差异(P0.05)。结论:限制性液体复合小剂量去甲肾上腺素对脓毒性休克患者有助于维持血流动力学稳定,改善全身氧代谢,减少并发症的发生,改善预后。     

Sympathetic and angiotensin-dependent hypertension during cage-switch stress in mice

The goal of this study was to determine the dependence of the acute hypertensive response to a novel model of acute psychosocial stress on the sympathetic and renin-angiotensin systems. Baseline mean arterial pressure (MAP), heart rate (HR), and locomotor activity were measured with telemetry in mice for a 1-h period and averaged 98 +/- 1 mmHg, 505 +/- 3 beats/min, and 5 +/- 1 counts, respectively. Stress was induced by placing a mouse into a cage previously occupied by a different male mouse, and this increased MAP, HR, and activity in the control group by 40 +/- 2 mmHg, 204 +/- 25 beats/min, and 68 +/- 6 counts, respectively. Each variable gradually returned to baseline levels by 90 min after beginning cage switch. Pretreatment with terazosin (10 mg/kg ip) significantly reduced the initial increase in MAP to 12 +/- 6 mmHg, whereas MAP for the last 45 min was superimposable on control values. Atenolol (10 mg/ml drinking water) had no effect to blunt the initial increase in MAP but had a growing effect from 10 min onward, decreasing MAP all the way to baseline by 60 min after starting cage switch. Captopril (2 mg/ml drinking water) treatment caused a very similar response. All three treatments significantly decreased the area under the blood pressure curve, and the blood pressure effect could not be attributed uniformly to effects on HR or activity. These data suggest that our novel model of psychosocial stress causes an initial alpha(1)-receptor-dependent increase in MAP. The later phase of the pressor response is blocked similarly by a beta(1)-receptor antagonist and an ACE inhibitor, independent of HR, suggesting that the beta(1)-dependent blood pressure effect is due, in large part, to the renin-angiotensin system.     

Increase in production of ascorbate radical in tissues of rat treated with paraquat

The production of ascorbate radical (A^·-) was investigated in tissues of rats intoxicated with paraquat (PQ) to know the protective role of antioxidant ascorbate (AH^·-) in tissues. The electron spin resonance (ESR) method is applied to observe A^·-. To eliminate increased biosynthesis of ascorbic acid (AH₂) by PQ intoxication, ODS rats were chosen and fed with or without 250 ppm PQ in the diet. The radical A^·- was detected only in the lung and spleen homogenates of both intoxicated and control rats at the beginning of ESR measurement. The radical levels of intoxicated rat lung and spleen were increased rapidly to twice the initial level after 3 h and decreased to 0.2-0.6 times the initial level after 24 h, whereas those of control rats were increased slowly to 1.1 times the initial level after 4 h and decreased slowly to 0.7 times the initial level after 24 h at 4°C. In other organs such as liver, kidney, heart and testis, A^·- was not detected initially but detected afterwards. Higher A^·- level was observed in the intoxicated rat liver than the control but no appreciable differences of A^·- levels were observed between the intoxicated kidney, heart and testis and the respective controls. In the intoxicated rat lung the concentration of AH₂ is only half but that of A^·- is twice as high as that of the control. Larger amounts of A^·- produced in the intoxicated rats decayed more quickly than those in the control rats. The simple addition of PQ to the control organ enhanced neither A^·- production nor A^·- quenching. These facts suggest that the tissues damaged by PQ require larger amounts of AH^- to detoxicate harmful oxidants, resulting in concomitant production of A^·-.     

超声引导下腰骶丛神经阻滞联合全身麻醉对老年髋关节置换术患者认知功能、氧化应激和血流动力学的影响

摘要 目的：探讨超声引导下腰骶丛神经阻滞联合全身麻醉对老年髋关节置换术患者认知功能、氧化应激和血流动力学的影响。方法：选取2018年1月~2020年1月期间我院收治的80例行髋关节置换术的老年患者,采用随机数字表法分为对照组（全身麻醉）和研究组（全身麻醉基础上联合超声引导下腰骶丛神经阻滞）各40例。比较两组患者认知功能、氧化应激、血流动力学、疼痛情况及不良反应。结果：两组麻醉前~术毕清醒时心率（HR）、平均动脉压（MAP）、脉搏血氧饱和度 （SpO₂）均呈先下降后升高趋势（P<0.05）;研究组麻醉10 min后SpO₂、MAP、HR高于对照组（P<0.05）。两组术前1 d~术后3 d超氧化物歧化酶（SOD）呈降低后升高趋势,丙二醛（MDA）呈升高后降低趋势（P<0.05）;研究组术后1 d、术后3 d的SOD高于对照组,MDA低于对照组（P<0.05）。两组术前1 d~术后3 d简易智能状态量表（MMSE）评分呈先降低后升高趋势,但研究组术后1 d、术后3 d评分高于对照组（P<0.05）。两组不良反应发生率对比无差异（P>0.05）。研究组术后1 h、术后12 h、术后24 h视觉疼痛模拟评分法（VAS）评分低于对照组（P<0.05）;两组术后48 h VAS评分比较无差异（P>0.05）。结论：老年髋关节置换术中应用超声引导下腰骶丛神经阻滞联合全身麻醉,可有效减轻机体血流波动、氧化应激以及对认知功能的损害,同时还可减轻患者术后早期疼痛,且安全性较好。     

不同的麻醉方案对脑幕上肿瘤手术患者麻醉苏醒期血流动力学的影响

摘要 目的：对比不同麻醉方案对脑幕上肿瘤手术患者麻醉苏醒期血流动力学的影响。方法：选取2017年10月至2019年10月于我院择期行脑幕上肿瘤手术患者为本次研究对象,将其随机分为研究组(n=40)和对照组(n=40)。对照组术中接受右美托咪定麻醉,研究组术中接受异氟醚麻醉,观察并对比研究组和对照组在麻醉诱导前(T₀)、麻醉后30 min(T₁)、麻醉后1 h(T₂)以及手术结束时(T3)血流动力学指标[心率(Heart rate,HR),平均动脉压(Mean arterial pressure,MAP)]、脑氧代谢情况[颈内静脉球部血氧饱和度(Oxygen saturation of the bulb of internal jugular vein,SjvO₂), 动脉血氧含量(Arterial oxygen content,CaO₂),脑静脉氧含量(Cerebral jugular venous oxygen content,CjvO₂),脑氧摄取率(Cerebralextractionofoxygen,CERO₂)],并分析研究组和对照组麻醉效果(优、良、差)和手术相关指标(手术时间、麻醉时间、苏醒时间、输液量)情况。结果：与T₀时相比,研究组和对照组在T₁~T₂时MAP和HR均降低,且对照组明显低于研究组(P<0.05);与T₀时相比,T₃时研究组MAP和HR均增加(P＜0.05);与T₀、T₁、T₃时相比,研究组和对照组T₂时MAP和HR均较低,对照组低于研究组(P<0.05);与T₀时相比,研究组和对照组在T₁~T₃时CjvO₂明显增高,CERO₂明显降低,研究组在T₁~T₃时CjvO₂高于对照组,研究组在T₁~T₃时CERO₂低于对照组(P<0.05),在T₀~T₃时研究组和对照组SjvO₂、CaO₂差异不明显(P＞0.05);与对照组相比,研究组患者麻醉效果优良率较高(P<0.05),苏醒时间明显缩短(P<0.05),研究组和对照组手术时间、麻醉时间、输液量差异不明显(P＞0.05)。结论：：右美托咪定用于脑幕上肿瘤手术患者麻醉效果较好,可以有效稳定血流动力学,降低脑氧代谢,缩短苏醒时间。     

喉罩通气下七氟醚全凭吸入麻醉在小儿先天性心脏病介入手术的临床麻醉效果

目的:探讨喉罩通气下七氟醚全凭吸入麻醉在小儿先天性心脏病介入手术的临床麻醉效果。方法:选取2017年4月～2019年5月期间我院收治的行先天性心脏病介入手术患儿98例,根据随机数字表法将其分为对照组(n=49)和研究组(n=49)。对照组给予氯胺酮诱导,全凭丙泊酚维持,面罩吸氧;研究组给予全凭七氟醚诱导、维持,喉罩通气。比较两组患儿麻醉前(T0)、切皮前(T1)、切皮后1 min(T2)、切皮后30 min(T3)、术后(T4)的血流动力学指标[平均动脉压(MAP)、心率(HR)]及应激反应指标[血糖、皮质醇],记录两组患儿手术时间、麻醉诱导时间、术后苏醒时间等围术期指标情况。记录两组围术期不良反应发生情况。结果:研究组手术时间、麻醉诱导时间、术后苏醒时间均短于对照组(P0.05)。两组T0时间点血糖、MAP、皮质醇、HR比较差异无统计学意义(P0.05);对照组T1～T4时间点MAP、血糖、皮质醇、HR均较T0升高(P0.05);研究组T1～T4时间点血糖、MAP、皮质醇、HR与T0时间点比较无差异(P0.05);研究组T1～T4时间点血糖、MAP、皮质醇、HR低于对照组(P0.05)。两组不良反应发生率比较无差异(P0.05)。结论:小儿先天性心脏病介入手术中应用喉罩通气下七氟醚全凭吸入麻醉,诱导迅速且安全、术后苏醒快、手术时间短,可有效维持血流动力学稳定,减少应激反应。