耳后注射复方倍他米松豚鼠血浆中药代动力学特征

目的 研究豚鼠耳后给药、全身给药后乙状窦及体循环血浆中复方倍他米松药物代谢动力学特征,探讨耳后给药的可能作用途径.方法 以复方倍他米松注射液(1 ml)为药物示踪剂,将豚鼠随机分成耳后注射(耳后组)及肌肉注射(肌注组)两组,每组50只,分别采集耳后及全身给药后0.5、1、1.5、2、3、5、7小时及1、2、4周双侧乙状窦及体循环血液,用高效液相色谱法分别检测其中的药物浓度.结果 ①乙状窦血:耳后组注射同侧乙状窦血中峰浓度(Cmax)最高,为对侧的2.56倍,为肌注组的3.03倍;耳后组注射同侧乙状窦血中药时曲线下面积(area under the ct curve,AUC)最高,为对侧的2.41倍,为肌注组的2.93倍.②体循环血:耳后给药体循环血中的药物浓度一直维持在较低的水平,耳后组Cmax为肌注组的0.13倍,耳后组AUC为肌注组的0.32倍.结论 耳后给药药物可能通过局部静脉回流在乙状窦中达到较高峰值,且持续时间相对较长,而在体循环血中一直保持着较低的浓度水平.     

川芎嗪在豚鼠血液、脑脊液和耳蜗外淋巴液中的分布

目的测定肌肉注射盐酸川芎嗪注射液后川芎嗪在豚鼠血液、脑脊液和耳蜗外淋巴液中的分布.方法豚鼠经肌肉注射盐酸川芎嗪注射液(2 ml/kg)后,采用高效液相色谱法(HPLC)中的内标法和外标法测定血液、脑脊液和耳蜗外淋巴液中川芎嗪的浓度.结果川芎嗪注射后,豚鼠血液中川芎嗪浓度迅速升高,20 min达到最大值(357.76 μg/ml),2 h后血药浓度迅速下降;在脑脊液中10 min后才检测到川芎嗪,20 min其浓度达到最大值(120.50 μg/ml),70 min后脑脊液药浓度迅速下降;在耳蜗外淋巴液中5 min时能检测到川芎嗪, 50 min时浓度达最大值(215.79 μg/ml),70 min后药物浓度明显降低.结论川芎嗪可吸收入血液并能够通过血脑屏障及血-迷路屏障进入脑脊液和耳蜗外淋巴液,药物吸收及消除迅速.临床应用该药时,要维持川芎嗪在耳蜗内的药物浓度应该适当增加用药次数,以提高疗效.     

耳后给药及鼓室给药外淋巴液药物浓度的实验观察

目的研究耳后皮下注射给药、鼓室内给药后外淋巴液中地塞米松磷酸钠的药物代谢动力学特征,探讨两种给药途径的药代动力学差异。方法以地塞米松磷酸钠(10mg/ml)为药物示踪剂,将豚鼠随机分为耳后注射(耳后组)和鼓室内给药(鼓室组)2组,耳后组给药量为1ml(10mg/ml),鼓室组给药量为0.1ml(10mg/ml),分别采集耳后组给药0.25、0.5、1、2.5、5、6、8小时外淋巴液及鼓室组给药后0.5、1、2、3、4、6、8小时外淋巴液,用高效液相色谱法分别检测其中的药物浓度。结果 1两种方式给药后,豚鼠外淋巴液中均可检测出地塞米松,且浓度均随时间的延长呈下降趋势;2鼓室组:给药后0.5~8h外淋巴液中均可检出有效药物成份地塞米松,3h达峰,其峰浓度(Cmax)最高为906.55mg/l,生物半衰期为1.27h。3耳后组:给药后0.25~8h可检出地塞米松,其达峰时间(Tmax)为0.25h,其峰浓度(Cmax)最高为18.83mg/l,生物半衰期为3.36h。4鼓室组给药量为0.1ml,耳后组给药量为1ml,外淋巴液中鼓室组地塞米松的浓度高于耳后组。5耳后组药物半衰期比鼓室给药组高。结论提示耳后皮下注射给药药物可能通过多种途径进入外淋巴,药物浓度相对鼓室给药低;鼓室给药组因避开血脑屏障及血迷路屏障故可较快进入外淋巴,保持较高药物浓度;结合临床我们可推测激素在外淋巴中可能低浓度即可起效。     

大鼠耳后和肌肉注射地塞米松后内耳组织药物浓度分析

目的探讨耳后注射和肌肉注射地塞米松磷酸钠两种不同给药方式内耳组织地塞米松浓度的差异。方法行双侧肾上腺切除术后将动物分三组：耳后注射组、肌肉注射组及生理盐水空白对照组。给药后0．25、0．5、2．5、5、12、24、72小时取材,内耳组织机械匀浆,利用酶联免疫吸附测定法检测地塞米松浓度。结果耳后注射组地塞米松浓度明显高于肌肉注射组,差异有统计学意义。耳后注射组在给药0．25小时后浓度达到高峰（175．2±36．0）ng／ml,然后逐渐下降,12小时后浓度明显下降,24小时几乎检测不到。肌肉注射组给药后2．5小时浓度达到高峰（141．1±8．9）ng／ml,5小时后明显下降,24小时几乎检测不到。结论与肌肉注射相比,给药后耳后注射组在内耳组织的局部药物浓度高,出现高峰早,持续时间长。     

豚鼠耳蜗内淋巴囊免疫反应后可诱导一氧化氮合酶的表达

在豚鼠耳蜗内淋巴囊注入钥孔(虫戚)血蓝素(KLH)之后，对豚鼠耳蜗内可诱导性一氧化氮合酶(iNOS或NOSⅡ)进行了免疫组织化学研究。所选实验动物为体重约350～400克的豚鼠12只，均被证实耳廓反射阳性，并用显微镜观察排除了中耳炎疾患。将动物分成两组，实验组注射KLH，对照组注射磷酸盐缓冲液(PBS)。实验组内淋巴囊内注射KLH后，每只动物耳……     

地塞米松鼓室内注射后在大鼠耳蜗中的分布

目的 观察不同浓度地塞米松鼓室内注射后在大鼠耳蜗中的分布及代谢规律.方法 144只SD大鼠全麻下鼓室内分别注射5 mg/ml、10 mg/ml和20 mg/ml地塞米松磷酸钠,并分别于注射后5 min、10 min、15 min、30 min、1 h、2 h,4 h,8 h、12 h、24 h、48 h及72 h处死动物,每个浓度、每个时间点4只大鼠.耳蜗标本处理后冰冻切片,免疫荧光法观察地塞米松在耳蜗组织中随时间的变化情况,并进行荧光半定量分析.另取4只正常sD大鼠采用免疫荧光方法 观察糖皮质激素受体在耳蜗内的分布.结果 地塞米松自注射后15 min起在耳蜗内始被检测到,30 min达到高峰,主要分布在螺旋韧带,Corti器和螺旋神经节.10 mg/ml组与20 mg/ml组各时间点的地塞米松浓度均高于5mg/ml组,持续时间亦从低浓度组的48 h延长至72 h.糖皮质激素受体亦主要分布于Corti器,螺旋神经节和螺旋韧带.结论 地塞米松鼓室内注射后可迅速到达耳蜗组织细胞中,其分布与糖皮质激素受体基本一致.增加地塞米松浓度可以提高其在耳蜗组织中的分布浓度,并延长其存留时间.     

125I标记碱性成纤维细胞生长因子脑脊液途径用药在豚鼠耳蜗分布及影响

目的 探讨碱性成纤维细胞生长因子(basic fibroblast growth factor，bFGF)进入内耳的途径及其在病理条件下对耳蜗及神经组织的保护作用机制。方法 将^125I标记bFGF(^125I-bFGF)采取侧脑室给药途径及生理和病理条件下肌肉给药途径注入豚鼠体内，测量相关组织γ放射计数率及耳蜗放射性自显影，观察^125I-bFGF在耳蜗分布及代谢情况。结果 生理和病理条件下，豚鼠肌肉注射^125I-bFGF后血液和肝脏组织中γ放射性计数率明显高于本底，而脑组织、耳蜗和外淋巴γ放射性计数率与本底比较，变化不明显，耳蜗放射性自显影未见显影颗粒；侧脑室注入^125I-bFGF 30min时，豚鼠血液、肝脏、脑组织、耳蜗及外淋巴γ放射性计数率均已增高，耳蜗放射自显影出现显影颗粒，脑及耳蜗组织γ计数率以2h和4h最高，8h明显下降，耳蜗放射性自显影仍可见显影颗粒，12hγ计数结果仍然高于本底，但耳蜗放射性自显影无明显显影颗粒，24h各脏器γ计数率接近本底；脑组织、耳蜗及血液γ放射性计数率始终保持平行变化。结论 生理情况下，bFGF肌肉注射难以通过血脑屏障和血迷路屏障，而bFGF侧脑室注入后可迅速通过脑脊液与内耳之间的交通径路进入内耳，分布于外淋巴中，且在耳蜗内潴留时间较长；病理情况下如急性缺氧、氨基甙类抗生素耳中毒时，bFGF肌肉注射亦难以通过血脑屏障和血迷路屏障到达内耳；两者对bFGF的通透具有方向性、相似性。     

耳后入路圆窗膜显微注射小鼠耳蜗基因转染新途径的研究

目的研究腺病毒携带目的基因经小鼠耳后人路圆窗膜显微注射途径耳蜗转导的可行性,为以小鼠作为动物模型的内耳基因治疗提供实验基础和解剖学依据。方法12只C57BL／6J小鼠分为2组,实验组（8只）以重组腺病毒携带的增强型绿色荧光蛋白基因（enhanced green fluorescent protein,EGFP）、对照组（4只）以人工外淋巴液经耳后入路圆窗膜显微注射注入耳蜗内。分别于术后5、14天取双侧耳蜗标本做基底膜铺片,在激光共聚焦显微镜下观察GFP表达。结果术后动物存活10只（每组死亡1只）。实验组转染后耳蜗底回基底膜及螺旋神经节上目的基因有表达,14天组强于5天组。对照组耳蜗未见荧光表达。结论耳后入路操作简单、损伤小、易于暴露圆窗龛。耳后入路圆窗膜显微注射腺病毒携带目的基因转导的方法能够将目的基因成功转导至耳蜗组织并表达。     

两种内淋巴给药方式对豚鼠耳蜗功能和形态的影响

目的 观察经耳蜗侧壁打孔(侧壁径路)和经圆窗膜、基底膜穿刺(双膜径路)两种内淋巴系统给药方式对豚鼠耳蜗整体形态结构和功能的影响并比较两种方式的优劣.方法 40只正常健康杂色豚鼠分为A、B两组(每组20只),所有动物左侧为给药耳,右侧为非给药耳.A组采用侧壁径路进入中阶灌注携带增强型绿色荧光蛋白基因的5型重组腺病毒(adenovirus5-enhanced green fluorescence protein,AdS-EGFP)5 μl;B组采用双膜径路进入中阶灌注AdS-EGFP 5μl.给药前后行听性脑干反应(ABR)测试,观察听功能改变.耳蜗冰冻切片直接荧光观察腺病毒分布,HE染色观察手术径路的愈合情况.基底膜铺片鬼笔环肽染色观察毛细胞受损情况,扫描电镜观察局部损害情况.结果 所有动物术后均存活.穿刺部位修复良好,耳蜗的完整性得以保持.EGFP在Corti器和血管纹内壁细胞内标记明显,表明两种给药径路都可以将药物成功注入内淋巴系统.A组证实成功14只(70%),手术前后ABR反应阈(声压级)变化[(33.1±10.3)dB]与对侧非给药耳[(9.4±3.9)dB]比较差异具有统计学意义(F=46.34,P=0.0005);B组证实成功8只(40%)手术前后阈值改变[(2.5±3.8)d8]与对侧耳[(2.5±3.8)dB]比较差异无统计学意义(F=0.00,P=1.000).两种方法在部分动物中都有药物渗漏入外淋巴的现象,给药局部产生炎性反应,侧壁径路对毛细胞的损害范围大于双膜径路.结论 两种手术径路都可将药物成功注人豚鼠耳蜗的内淋巴系统中,局部有炎性反应,术后耳蜗的完整性可以获得完全恢复.侧壁径路对豚鼠耳蜗毛细胞缺失和ABR反应阈的影响大于双膜径路,但是经侧壁径路进入中阶的手术成功率高于双膜径路,选择何种灌注径路需要根据实验要求来定.     

治疗美尼尔氏病的内淋巴囊分流术

本文介绍给32例美尼尔氏病患者采用内淋巴囊分流术的治疗效果。手术步骤:全麻下耳后切口,用高速电钻施行单纯乳突凿开,保留修薄的外耳道后壁,刮平中、后颅窝骨板,使水平、后半规管、窦脑角充分暴露,乙状窦的位置若靠前,暴露有困难时则用大的钻石钻头将乙状窦乳突面骨质磨去,这样在手术过程中乙状窦就可以用骨蜡将其压瘪。内淋巴囊的位置若极靠前下接近颈静脉球,则常常位于后半规管下缘,在面神经管乳突段的内侧,只要熟知面神经的解剖即可迅速暴露内淋巴囊。     

单纯内淋巴囊减压术治疗梅尼埃病的远期疗效

报告以单纯内淋巴囊减压术治疗梅尼埃病５８例中，经随访５－６．５年的３０例眩晕完全消失者２１例。表明单纯内淋巴囊闰坟术与内淋巴囊切开术或分流术的疗效近似而且引起严重并发症的机会较少。并对本手术的作用机理，操作要领及并发症的预防等进行讨论。     

Endolymphatic sac drainage and steroid-instillation surgery (EDSS) for intractable Meniere's disease

Endolymphatic sac surgery is one of the most widely accepted techniques used to treat intractable Meniere's disease. To improve this surgery, we developed the following techniques: A simple mastoidectomy was used to expose the endolymphatic sac between the sigmoid sinus and inferior margin of the posterior semicircular canal. The sac was opened and filled with a mass of prednisolone. A bundle of absorbable gelatin films was then inserted into the sac lumen to expand it, followed by gelatin sponges dipped in a high concentration of dexamethasone. Long-term results (17-32 months) in 20 patients with intractable Meniere's disease treated with endolymphatic sac drainage and steroid-insertion surgery (EDSS) showed that definitive spells were completely controlled in 15 of 20 cases (75%); all reports of vertigo decreased; hearing improved in 12 of 20 cases (60%); and annoyance due to tinnitus decreased in 15 of 20 cases (75%). Steroids directly instilled into the endolymphatic cavity may thus be more effective with the diseased inner ear organs than those applied via any other route. Draining of endolymphatic fluid at the sac into the mastoid cavity also contributed to these satisfactory EDSS results.     

The vascular pattern of the endolymphatic sac in the human embryo

The venous vascular anatomy of the endolymphatic sac in human embryos was examined. The endolymphatic sac was found to be covered by sinusoid-like blood vessels arising from the sigmoid sinus. A rich and extensive capillary network was present on the epithelial surface of the endolymphatic sac. Connections between this capillary bed and the vein in the paravestibular canaliculus were seen. The blood of the endolymphatic sac can therefore drain either into the vein of the vestibular aqueduct in the paravestibular canaliculus or directly into the sigmoid sinus. The vessels lying on the endolymphatic sac are thin-walled and irregular. The endothelial cells lies in direct contact with the epithelial cells of the endolymphatic sac. The reduction of the dense capillary bed in the young embryo to only a few vessels in the order embryo is described.     

用4.7特斯拉磁共振成像活体内观测豚鼠实验性内淋巴积水

目的探讨用4.7特斯拉试验用磁共振成像系统能否在豚鼠中检测内淋巴积水.方法20只白色或者杂色豚鼠用于该研究.5只正常豚鼠作为对照组,15只豚鼠用于制作内淋巴积水模型.9只内淋巴囊破坏组中的5只和6只内淋巴囊完整组(与乙状窦游离)动物采用gadolinium(Gd)-DTPA-BMA增强MRI检测内淋巴积水.结果由于Gd-DTPA-BMA主要进入鼓阶和前庭阶,耳蜗的三个阶可在所有动物中由MRI清晰显示.在内淋巴囊完整组,内淋巴囊手术后6天MRI即可检测到内淋巴积水,并且由组织学证实.在内淋巴囊破坏组中的1只动物,因内耳屏障的严重破坏而使Gd-DTPA-BMA快速漏入中阶,MRI可检测到该变化,其听力损失为60dB.结论用Gd-DTPA-BMA增强的高分辨MRI可检测出内淋巴积水,有可能对积水程度进行定量测试.在Gd-DTPA-BMA的帮助下,内耳屏障损伤或可能的膜破裂可以被检出.     

Histology of the endolymphatic sac of the rat ear and its relationship to surrounding blood vessels: the "endolymphatic glomerulus"

Histologic and histochemical studies of the endolymphatic sac of full-term rat fetuses were undertaken to clarify the anatomy of the endolymphatic sac, and the mechanism of endolymph circulation and regulation. Hitherto undescribed structure enveloping the sac with blood vessels extending from the sigmoid sinus resembling the kidney glomerulus was seen. This endolymphatic "glomerulus" is believed to provide a means of active exchange of water and electrolytes between blood vessels and the endolymphatic sac.     

Expression of caspase-activated deoxyribonuclease (CAD) and caspase 3 (CPP32) in the hydropic cochlea of guinea pigs – second report

Apoptosis was induced in the cochlea by the injection of keyhole limpet hemocyanin (KLH) into the endolymphatic sac of guinea pigs and immunohistochemically examined. Keyhole limpet hemocyanin was injected into the right endolymphatic sac. The temporal bones were fixed via cardiac infusion of fixative and immunohistochemically stained for caspase-activated deoxyribonuclease or caspase 3. Endolymphatic hydrops became evident in the cochlea 1 day after the injection of keyhole limpet hemocyanin (n=6). The temporal bones in the control group did not show any caspase-activated deoxyribonuclease or caspase 3 immunoreactivity (n=6). Immunoreactivity for caspase 3 was detected in the supporting cells of the organ of Corti, the stria vascularis and the spiral ganglion cells. Caspase-activated deoxyribonuclease was also detected in the same areas. These findings suggest that apoptosis is involved in the pathogenesis of endolymphatic hydrops. This phenomenon could lead to cochlear dysfunction, as seen in endolymphatic hydrops.     

Variations in surgical anatomy of the endolymphatic sac

Twenty-nine specimens of the extraosseous portion of the human endolymphatic sac (ES) were serially sectioned longitudinally. The length and width of the extraosseous ES were measured and the surface area was calculated. As the specimens included the sigmoid sinus (SS), the relationship between the ES and the SS was analyzed. The extraosseous ES varied considerably in size. The lumen either consisted of a single tube or was subdivided into several tubules. The distal part of the ES overlapped the SS in one third of the specimens. The results indicate that a minute extraosseous ES could explain the sometimes difficult task of localizing this structure at ES surgery. The great variability in size might perhaps also explain the varying results of this surgery.     

内淋巴囊对外源性TD抗原的清除作用

目的:探讨内淋巴囊对外源性胸腺依赖性(TD)抗原的吞噬和清除作用。方法:用S-D大鼠30只,以TD抗原钥孔(?)血蓝蛋白(KLH)全身免疫后2周,再次在内耳接种相同抗原,分别于此后1 h、3 h、1 d、3 d、7 d和14 d,取颞骨作组织学处理、冰冻切片,用抗KLH单克隆抗体,运用免疫组织化学技术,观察内耳免疫应答过程中内淋巴囊腔内KLH的动态变化。结果:内耳抗原接种后3 h,内淋巴囊出现KLH;第1～7 d在内淋巴囊的抗原被捕捉吞噬和递呈;第14天内淋巴囊仅发现微弱的抗原染色。结论:在内耳的二次应答中,内淋巴囊能够吞噬、处理和清除外源性抗原说明其具有免疫防御和免疫应答功能。     

A potential portal flow in the inner ear

OBJECTIVES/HYPOTHESIS: The aim of the present study was to visualize the flow direction of blood in the extraosseous part of the vein of the vestibular aqueduct (VVA) and to explore the effect of an induced obstruction in the distal part of the VVA before it merges with the sigmoid sinus. The endolymphatic sac has been implicated as a potential endocrine gland, which venules drain to the VVA. A reversal of the direction of flow in the VVA toward the inner ear could, through vestibular arteriovenous anastomosis, cause portal circulation in the inner ear. STUDY DESIGN: The authors conducted an experimental animal study using in vivo fluorescence microscopy. RESULTS: Obstructing the distal part of the VVA just before it empties into the sigmoid sinus immediately reverses the flow of blood in the VVA toward the inner ear. CONCLUSIONS: After an obstruction of the VVA, the drained venous blood from the endolymphatic sac may enter a portal circulation in the inner ear, which could cause disturbances in the endolymph homeostasis and potentially symptoms as seen in Meniere disease.     

Ischemia of the endolymphatic sac.

A decrease in vascular density in the endolymphatic sac was suspected as a factor in the pathogenesis of endolymphatic hydrops in Meniere's disease. The present study was undertaken to explore this possibility by cutting the posterior meningeal artery and the sigmoid sinus above and below the external aperture of the vestibular aqueduct or by incision of the dura adjacent to the sinus in 18 guinea pigs. The lesions in the sac were greater in the segmental ablation of the artery and sinus and were consistently associated with the development of endolymphatic hydrops. Among the lesions shown in the sac epithelia, the intermediate portion was most often and most severely affected with a decrease in rugose formation and a flattening of the tall epithelial cells or replacement of epithelial cells by squamous type cells. A high correlation between the lesions in the intermediate portion and occurrence of hydrops suggests that the intermediate portion plays a greater role in the pathogenesis of endolymphatic hydrops. The sac luminal precipitates known to be increased in human Meniere's cases were decreased or absent in this study, which suggests that the increased amount is unlikely to be the cause of endolymphatic hydrops. The evidence supports the hypothesis that these substances are secreted by the endolymphatic sac. The limited sensory cell lesions seen in the cochleae and saccules are likely to be due to a temporary vascular ischemia and endolymphatic hydrops.