Characterization of α1-adrenoceptor subtypes mediating contractions to phenylephrine in rat thoracic aorta,mesenteric artery and pulmonary artery

1. The subtype of α₁-adrenoceptor mediating contractions to phenylephrine of the rat thoracic aorta, mesenteric artery and pulmonary artery were investigated by use of antagonists which show selectivity between the cloned α₁-adrenoceptor subtypes in binding studies.
2. Cumulative concentration-contraction curves for phenylephrine were competitively antagonized in the rat thoracic aorta by prazosin (pA₂ 9.9), WB4101 (pA₂ 9.6), 5-methylurapidil (pA₂ 8.1), benoxathian (pA₂ 9.2) and indoramin (pA₂ 7.4). These compounds were also competitive antagonists in the mesenteric and pulmonary arteries (except for 5-methylurapidil in the pulmonary artery), (prazosin pA₂ 9.9 and 9.7; WB4101 pA₂ 9.8 and 9.6; 5-methylurapidil pA₂ 7.9 and pK_B estimate 8.0; benoxathian pA₂ 8.8 and 9.3; indoramin pA₂ 7.2 and 7.5, respectively).
3. RS 17053 was not a competitive antagonist in any blood vessel as Schild plot slopes were greater than unity. The pK_B estimates for RS 17053 were 7.1 in aorta, 7.0 in the mesenteric artery and 7.7 in the pulmonary artery.
4. The α_1D-subtype selective antagonist BMY 7378 appeared to be non-competitive with shallow Schild plot slopes. The data were better fitted with two lines in all tissues, with Schild plot slopes that were no longer different from unity, except in the pulmonary artery. The higher affinity site for BMY 7378 in the aorta had a pA₂ of 9.0, while it was 8.8 and 8.9 in the mesenteric and pulmonary arteries, respectively.
5. MDL73005EF acted in a non-competitive manner in all three blood vessels, with shallow Schild plot slopes. The pK_B estimates for MDL73005EF were 8.4 in aorta, 7.5 in the mesenteric artery and 8.0 in the pulmonary artery.
6. In all three blood vessels the functionally determined antagonist affinity estimates correlated best with published pK_i values for their displacement of [³H]-prazosin binding on membranes expressing cloned α_1d-adrenoceptors compared with α_1a- or α_1b-adrenoceptors. The antagonist affinity estimates in the aorta, mesenteric and pulmonary arteries correlated highly with their previously published pA₂ values in rat aorta (α_1D) and less well with those for α_1A- and α_1B-adrenoceptors mediating contraction of the rat epididymal vas deferens and rat spleen, respectively.
7. The results of this study suggest that the contraction to phenylephrine of the rat thoracic aorta, mesenteric artery and pulmonary artery are mediated in part via the α_1D-subtype of adrenoceptor. The data for both BMY 7378 and MDL73005EF in all three blood vessels are consistent with receptor heterogeneity. However, the identity of the second site is unclear.

     

An external approach without tracheotomy for submucosal cordectomy with laterofixation for bilateral abductor paralysis of the vocal folds

There are numerous surgical procedures now available to manage bilateral abductor paralyses of the vocal folds. These procedures have various success rates but mostly do not offer reliable and predictable postoperative results, and usually require ,tracheotomy. The technique described in this report is based on a trial study to obtain a safe airway for an affected patient and avoid tracheotomy, if possible. Submucosal cordectomy was used with lateral fixation of one vocal fold and preservation of the arytenoid. The procedure was performed by using continuous intravenous anesthesia, which does not require intubation of the patient's airway. Seven patients were operated with this technique with excellent postoperative results. The glottal airway was largely improved in all patients, with only minor temporary complications.     

Anaesthetic management of a patient with a descending thoracic aortic aneurysm and severe bilateral bullous pulmonary parenchymal disease

The anaesthetic management of the surgical repair of a descending aortic aneurysm in a patient with large, bilateral, pulmonary bullae is described. Anaesthesia for descending aortic surgery normally involves unilateral, positive-pressure ventilation, an option which poses some risk of barotrauma in the presence of bilateral bullae. Patients with bullous disease commonly have severe lung disease and thorough preoperative assessment and preparation are necessary. Intraoperatively, bilateral rupture of the bullae could be catastrophic and preparations should be made for this possibility. In order to diminish this risk, a surgical technique including preemptive collapse of the bulla by minithoracotomy and tube drainage, with use of a bronchial blocker to the affected part of the lung may be used. If rupture occurs, then high frequency jet ventilation may be effective. Use of a double lumen endobronchial tube may be advantageous for patients with either unilateral and bilateral bullae. Anaesthesia for patients with bullae should avoid positive-pressure ventilation and nitrous oxide in order to limit the risk of barotrauma from a ball valve mechanism. In this case, the risk of barotrauma was reduced by performing an inhalational induction of anaesthesia and limiting peak inflation pressures during thoracotomy. It was elected to use positivepressure ventilation through a double lumen endobronchial tube following chest incision. A high frequency jet ventilator was available but not employed. Anaesthetic management was complicated by the presence of pleural adhesions, surgical approach directly through a bulla, and the requirement for one lung ventilation. The de i’aone descendante aecouverte cnez un pattent porde grosses bulles bilatérales d’emphysème est discutée, esthésie habituelle pour une chirurgie de l’aorte descendante site une ventilation mécanique unilatérale et constitue ainsi sque additionnel pour le porteur de bulles emphysémas bilatérales. Ces patients ont ordinairement des affections onaires graves et l’évaluation et la préparation préopéraprennent une importance spéciale. Pendant l’intervention, pture de bulles bilatérales peut être catastrophique et il se préparer à cette éventualité. Pour minimiser ce risque, technique chirurgicale qui inclut le collapsus préventif de lle par minithoracotomie et drainage, avec installation d’un ieur bronchique sur la partie atteinte du poumon. Si une re survient, le passage à la ventilation par jet à haute tence peut être salutaire. Le tube endobronchique à double ère peut présenter des avantages aussi bien dans les cas ulles unilatérales que bilatérales. Chez ces patients, il vaut x s’abstenir de ventiler avec une pression positive et du xyde d’azote afin de limiter le risque de barotraumisme soupape. Dans ce cas-ci, on a réussi à limiter le risque arotraumatisme en réalisant une induction par inhalation réduisant la pression d’inflation de pointe pendant la cotomie. Après l’incision thoracique, on a choisi d’utiliser tilation mécanique avec un tube endobronchique à double ère. Un ventilateur à jet à haute fréquence était prêt mais as été utilisé. La gestion de l’anesthésie a été compliquée par dhérences pleurales, par la rencontre d’une bulle d’emphysà l’incision et par l’obligation de ventiler un seul poumon.     

44例脓胸的外科治疗

目的：探讨脓胸的治疗方法。方法：根据已出院的44例脓胸患者的治疗资料进行分析。结果：胸腔闭式引流、胸腔灌洗是治疗中不可缺少的手段。结论：在全身治疗的基础上,配合胸腔闭式引流、胸腔灌洗、必要的外科手术可望取得较为理想的治疗结果。     

胸段硬膜外麻醉对神经肽Y的影响

为探讨胸段硬膜外麻醉对患者血浆ＮＰＹ的影响,本文采用放射免疫分析法测定了３１ 例择期上腹部手术病人胸段硬膜外麻醉前后血浆ＮＰＹ的含量。结果显示：麻醉后平均动脉压较麻醉前显著下降（ Ｐ＜０－０１） ,血浆ＮＰＹ则无显著变化（ Ｐ＞ ０－０５）。提示患者处于硬膜外麻醉状态下体内ＮＰＹ 含量的变化与交感神经系统调节具有一定的关系。     

臂丛下干的应用解剖观察

目的了解斜角肌间隙内臂丛下干与邻近组织结构及胸１神经干与第１肋的关系,为临床诊治臂丛下干卡压症提供解剖学依据。②方法在２１具４２侧成人标本上观测臂丛下干与邻近结构的位置关系。③结果在４２侧标本的斜角肌间隙内,有３３侧在前斜角肌的后内侧存在孤立的肌束,臂丛下干分别从其前下方（２３侧）或后上方（１０侧）通过;组成臂丛下干的胸１神经干在斜越第１肋前内侧面时部分穿行于骨纤维管内。④结论该肌束的压迫或拱抬均可成为臂丛下干受压的因素之一;组成臂丛下干的胸１神经干在越过第１肋时易受压迫。     

戈米辛J和异型南五味子丁素对大鼠胸主动脉的作用

目的研究由南五味子属药用植物分离的戈米辛Ｊ（ｇｏｍｉｓｉｎＪ,ＧＪ）和异型南五味子丁素（ｈｅｔｅｒｏｃｌｉｔｉｎＤ,ＨＤ）对血管平滑肌的作用。方法采用离体大鼠胸主动脉标本,观察他们对高钾去极化收缩和对ＣａＣｌ２、ＮＡ量效曲线的影响。结果ＧＪ和ＨＤ能抑制ＫＣｌ所致的收缩,其ＩＣ５０（９５％可信限）分别为３．８（２．４～５．９）和７．５（１．４～３９）μｍｏｌ／Ｌ;ＧＪ和ＨＤ能使ＣａＣｌ２量效曲线右移,最大效应降低,其ｐＤ′２值分别为５．１３±０．０７和４．７７±０．１８;ＧＪ和ＨＤ也可使ＮＡ量效曲线右移和最大效应降低,其ｐＤ′２值分别为３．７２±０．２３和３．３１±０．２７。结论ＧＪ和ＨＤ能抑制ＫＣｌ、ＣａＣｌ２和ＮＡ产生的血管收缩,而且对ＣａＣｌ２的致缩作用强于对ＮＡ的收缩作用,提示他们具有钙拮抗活性。     

The long-term results of upper dorsal sympathetic ganglionectomy and endoscopic thoracic sympathectomy for palmar hyperhidrosis

To assess and compare the long-term results of upper dorsal sympathetic ganglionectomy (UDS) and endoscopic thoracic sympathectomy (ETS), we examined 84 patients who underwent UDS and 71 patients who underwent ETS for the treatment of palmar hyperhidrosis. The period of follow-up ranged from 37 to 228 months. The immediate success rate was 100% in the UDS group and 98.6% in the ETS group. Troublesome compensatory hyperhidrosis occurred in 67.8% of the UDS patients and 84.8% of the ETS patients; however, 55% of the UDS patients and 63% of the ETS patients felt satisfied with their operation. The main reasons for dissatisfaction were recurrence and compensatory hyperhidrosis. Interestingly, simultaneous cure of plantar hyperhidrosis occurred in 28 (40%) of the UDS patients and 28 (44%) of the ETS patients with concomitant plantar hyperhidrosis. ETS required both a shorter operation time and hospital stay than UDS. Thus, we now perform ETS as the treatment of choice because of its excellent illumination and adequate magnification via a minimally invasive approach. The use of ETS as the first choice of treatment for palmar hyperhidrosis is supported not only by the immediate results, complications, and cure of plantar hyperhidrosis, but also by the long-term results. Nevertheless, compensatory hyperhidrosis was also a major complication after ETS.     

Thoracic Aortic Aneurysms: Role of Echocardiography

This article describes the evolving role of echocardiography for the detection and evaluation of thoracic aortic aneurysms. A brief summary of the clinical, anatomical, and pathological features of the etiologic categories of thoracic aneurysms is presented. The advantages and limitations of echocardiography and its comparison with other techniques (computed tomographic scanning, magnetic resonance imaging, and aortography) are discussed.     

Bilateral traumatic abducens nerve paralysis with cervical spine flexion injury

Bilateral traumatic abducens nerve palsy is a rare condition. We report a case associated with cervical spine flexion injury. This may be the first such case report, as no similar case was found in our review of the literature. The mechanisms of injury in this case are relevant to theories that explain hyperextension injuries.