从六经传变理论探“虚不受补”

[目的]从六经传变角度分析"虚不受补"的内在机理,探索完善临床遇见的"虚不受补"问题。[方法]归纳疾病传变如五脏、六经、表里传变的一般规律,总结各类传变的治疗原则,辨析虚实辨证和补法分类,分析产生"虚不受补"的常见现象,提出正确进补的原则与条件。[结果](1)有外感、肺部邪气重,先解表、宣肺,然后才能进补;(2)肠胃有邪气,不可进补,先泄邪气通腑然后可进补;(3)少阳枢机不利则气机不畅,不可进补,先理气转机方可进补;(4)疾病的治疗有表里虚实之辨,也有标本缓急之别,标本之辨在辨证施治时至关重要。[结论]"虚不受补"大多数时候是进补顺序错误导致,在进补前辨别人体的气血状态,对症施药,则可以缓解甚至消除因为进补不当带来的不舒适。解表、健脾胃、活气血、寓消于补是解决虚不受补问题的重要途径。     

线粒体ATP敏感性钾通道在头部浅低温减轻大鼠全脑缺血再灌注损伤中的作用

目的 评价线粒体ATP敏感性钾通道在头部浅低温减轻大鼠全脑缺血再灌注损伤中的作用.方法 健康雄性SD大鼠32只,体重200～250 g,随机分为4组(n=8):假手术组(S组)、全脑缺血再灌注组(I/R组)、头部浅低温组(H组)和5-羟基葵酸钠组(5-HD组).采用三血管阻断法建立大鼠全脑缺血再灌注模型.S组仅分离血管,不阻断;I/R组制备大鼠全脑缺血再灌注模型;H组于再灌注前即刻实施头部浅低温(使鼓膜温度在1 min内降至32～34℃),维持3 h后复温;5-HD组于缺血前30 min腹腔注射5-羟基葵酸钠10 mg/kg,于再灌注前即刻实施头部浅低温.于再灌注12 h时评估大鼠神经行为学(跨格次数和转体时间),采用EIJSA法测定血清神经元特异性烯醇化酶(NSE)的浓度,电镜下观察额叶皮质神经元的超微结构.结果 与S组比较,I/R组、H组和5-HD组跨格次数减少,转体时间延长,I/R组和5-HD组血清NSE浓度升高(P<0.05),H组血清NSE浓度差异无统计学意义(P0.05);与I/R组比较,H组跨格次数增多,转体时间缩短,血清NSE浓度降低,5-HD组转体时间缩短(P<0.05),其余指标差异无统计学意义(P0.05);与H组比较,5-HD组跨格次数减少,转体时间延长,血清NSE浓度升高(P<0.05).H组额叶皮质神经元病理学改变较I/R组和5-HD组减轻,5-HD组与I/R组损伤程度相似.结论 头部浅低温减轻大鼠全脑缺血再灌注损伤可能与开放线粒体ATP敏感性钾通道有关.     

罗哌卡因和布比卡因对豚鼠心室肌细胞L-型钙电流的影响

目的观察罗哌卡因和布比卡因对豚鼠心室肌细胞L-型钙电流(ICa-L)的影响,探讨其心肌负性肌力作用的机制。方法以急性酶解法获得豚鼠的单个心室肌细胞,用标准的全细胞膜片钳技术记录ICa-L。结果100/μmol/L的罗哌卡因和布比卡因分别使豚鼠心室肌细胞ICa-L峰值降低(37±3)%和(42±5)%,两者比较差异有统计学意义(P<0.05);两种药物均使电流密度-电压曲线上移,但不改变激活ICa-L的电压和曲线的形态。罗哌卡因和布比卡因均呈浓度依赖性阻滞豚鼠心室肌细胞ICa-L,半最大抑制浓度分别为212±38、(161±20)μmol/L。结论罗哌卡因和布比卡因均呈浓度依赖性阻滞豚鼠心室肌细胞ICa-L,可能是其产生心肌负性肌力作用的主要机制。     

含钾通道开放剂的HTK液对大鼠心功能以及线粒体结构和功能的影响

目的 观察含钾通道开放剂的供心保存液对心功能以及能量代谢、线粒体呼吸酶活性及超微结构的影响.方法 将SD大鼠分为HTK组、Pi组、5HD组、1098组和5HD+1098组.切取SD大鼠心脏,建立Langendorff灌注模型,平衡10 min,然后按分组进行如下处理:HTK组心脏以Histidine-Tryptophan-Ketoglutarate液(HTK液)停搏;Pi组心脏以含0.5 mmol/L吡那地尔(Pi)的HTK液停搏;1098组心脏以含0.5 mmol/L Pi和100 μmol/L HMR1098的HTK液停搏;5HD组心脏以含0.5 mmol/L Pi和100 μmol/L五羟葵酸(5HD)的HTK液停搏;5HD+1098组心脏以含0.5 μmol/L Pi、100 μmol/L 5HD和100μmol/L HMR1098的HTK液停搏.停搏后,将心脏置于各组相应的液体(4℃)中保存8 h,然后用含氧的37℃克-亨液(K-H液)再灌注60 min.观察各组平衡末、保存末、再灌注末时的心功能、线粒体呼吸酶活性、心肌ATP含量及心肌细胞线粒体超微结构的改变.结果 Pi组保存末、再灌注末的心功能(心率、左心室舒张末压、左心室发展压和冠状动脉流量)、心肌线粒体呼吸酶(NADH氧化酶、琥珀酸氧化酶、细胞色素C氧化酶)活性及ATP含量均优于其他各组(P<0.01或P<0.05),同时线粒体的结构改变也最轻.结论 含Pi的HTK液能改善大鼠心脏保存效果;Pi对能量状态的维持以及对线粒体结构与功能的保护可能是其心肌保护的重要机制.     

中电导型钙依赖钾通道在糖尿病大鼠阴茎海绵体中的表达及意义

目的 探讨糖尿病对大鼠阴茎海绵体中电导钙激活性钾通道蛋白(IKCa)表达的影响以及意义.方法 选用SD雄性大鼠35只,随机选择25只用于制作糖尿病动物模型,剩余10只用于空白对照.造模成功后饲养8周,注射阿朴吗啡(APO),观察大鼠阴茎勃起,同时采用逆转录-聚合酶链反应(RT-PCR)和Western blot技术检测IKCa mRNA和蛋白在大鼠海绵体的表达.结果 DM组大鼠阴茎勃起和IKCa mRNA及蛋白表达均显著低于STZ组和NDM组(P<0.05),STZ组和NDM组之间大鼠阴茎勃起情况和IKCa mRNA及蛋白表达无统计学意义(P>0.05).绪论糖尿病可降低大鼠阴茎勃起功能,IKCa在糖尿病大鼠海绵体表达明显降低.糖尿病对大鼠阴茎勃起功能的影响与阴茎海绵体IKCa表达减少密切相关.     

Changes in vascularity of cartilage endplate of degenerated intervertebral discs in response to melatonin administration in rats

We carried out an experimental investigation of cartilage endplate vascularity of degenerated intervertebral discs produced by exogenous melatonin (MEL) treatment. Adult Swiss albino rats were divided into three groups: control, operated degeneration, and MEL treatment. There were five rats in each group and, using a posterior approach, cuts were made parallel to the endplates in the posterior annulus fibrosus in five consecutive intervertebral discs between the 5th and 10th vertebral segments of the rats' tails. At 8 weeks, five of these animals were treated with exogenous MEL (s.c. injection of 30 μg/100 g body weight daily for 4 weeks). In each experimental group, one animal was examined using CT scanner to study the density of the cartilage endplate of the disc. To evaluate the bone growth and vascularity of the cartilage endplate region, the animals were killed for subsequent histopathological evaluation. We found that the vascular channel counts and percentage areas from animals treated with MEL were significantly lower than from the operated degeneration animals. Accordingly, the density histogram in the MEL group showed a spike profile for both the vertebral body and the cartilage endplate, indicating an increase in the amount of higher density tissues in these regions. Our results demonstrate that the use of MEL reduces the cartilage endplate vascularity of degenerated intervertebral discs, suggesting that it may have an osteoinductive effect on bone formation. Further studies are needed to characterize fully the relevance of our findings for the treatment of disorders such as postmenopausal osteoporosis.     

异丙酚对大鼠海马CA1缺血神经元持续钠电流的影响

目的 探讨异丙酚对大鼠海马CA1缺血神经元持续钠电流的影响。方法 酶消化法急性分离SD大鼠海马CA1锥体细胞,通过低氧和无糖法制备神经元缺血模型,全细胞膜片钳技术记录异丙酚对缺血神经元持续钠电流的影响。结果 神经元缺血5 min后持续钠电流显著增强。异丙酚10μmol/L和100μmol/L均能明显抑制缺血引起的持续钠电流增强(与0μmmol/L组比,P<0.01),此作用为异丙酚100μmol/L较10μmol/L儿更强(P<0.05)。结论 异丙酚能够抑制体外脑缺血时海马神经元持续钠电流,这可能是其产生脑保护作用的机制之一。     

背根神经节Nav1.8磷酸化在大鼠糖尿病痛性周围神经病变中的作用

目的 本研究采用射频热凝毁损腰交感神经节,探讨背根神经节（DRG）Nav1．8磷酸化在大鼠糖尿病痛性周围神经病变中的作用。方法 采用腹腔注射链尿佐菌素诱导糖尿病痛性周围神经病变大鼠模型,取造模成功的大鼠20只,随机分为糖尿病对照组（D组）及交感神经节射频热凝组（R组）,每组10只,另取10只同月龄大鼠为正常对照组（C组）。R组大鼠在X光机介导下行右侧L3,4椎旁腰交感神经节射频热凝毁损。分别于射频热凝前、射频热凝后1、2周时,采用von Frey纤维丝测定大鼠右侧后爪对机械性刺激缩足反应的阈值（PWT）;射频热凝后2周,采用Western-blotting方法测定DRG细胞Nav1．8蛋白和苏氨酸磷酸化Nav1．8蛋白表达,并采用透射电镜观察大鼠腓肠神经超微病理结构。结果 与C组比较,射频热凝前D组和R组PWT降低（P＜0．01）。射频热凝后1～2周,R组较D组PWT升高,但仍较C组降低（P＜0．05）。C组髓鞘排列均匀,轴突内可见形态正常的线粒体;D组脱髓鞘明显,髓鞘板层排列紊乱、断裂、肿胀;R组脱髓鞘程度明显减轻,髓鞘板层局部排列紊乱、空泡形成。与C组比较,D组和R组Nav1．8蛋白表达降低（P＜0．05）,而苏氨酸磷酸化Nav1．8蛋白表达增高（P＜0．01）;R组苏氨酸磷酸化Nav1．8蛋白表达低于D组（P＜0．05）。结论 DRG细胞Nav1．8的磷酸化可能是糖尿病痛性周围神经病变大鼠痛觉过敏形成的机制之一。     

Potassium channels and human corporeal smooth muscle cell tone: further evidence of the physiological relevance of the Maxi-K channel subtype to the regulation of human corporeal smooth muscle tone in vitro

PURPOSE: Recent evidence indicates that the large conductance, voltage dependent, Ca2+ sensitive K channel or Maxi-K has an important role in the modulation of human corporeal smooth muscle tone and, thus, in erectile capacity. We further clarified the contribution of the Maxi-K channel subtype to the generation of contractile responses in isolated human corporeal tissue strips. MATERIALS AND METHODS: We performed pharmacological studies of phenylephrine contracted isolated corporeal tissue strips in the presence and absence of the 2 Maxi-K channel blockers tetraethylammonium chloride (TEA) and charybdotoxin, and the Maxi-K opener NS1619. K channel treatment effects were evaluated using 2 parameters, including 1) the steady state parameter of the empirically determined peak magnitude of the steady state contractile response and 2) the kinetic parameter of time required to achieve half of the peak steady state contractile response or half-time. Electrophysiological studies in freshly isolated and cultured myocytes were performed in parallel to corroborate findings further at the tissue level. RESULTS: Pre-incubating isolated human corporeal tissue strips with 1 mM. TEA and 1 microM. charybdotoxin was associated with an approximate 20% increase in the peak steady state contractile response and a corresponding approximate 20% decrease in the half-time of the phenylephrine induced contractile response. Conversely, pre-incubation with 10 microM. NS1619 produced a significant, approximately 20% decrease in the peak steady state contractile response and an approximate 38% increase in the half-time of the phenylephrine induced contractile response. Adding 30 to 180 microM. NS1619 to phenylephrine pre-contracted smooth muscle strips resulted in a 30% to 50% reduction in steady state contractile tension. No detectable effect of NS1619 was observed in 120 mM. KCl or 100 mM. TEA pre-contracted corporeal tissue strips. Whole cell recordings of freshly isolated and cultured corporeal myocytes confirmed that 30 microM. NS1619 induced a charybdotoxin sensitive hyperpolarizing current mediated by the Maxi-K channel. CONCLUSIONS: These in vitro studies confirm and extend previous observations indicating the importance of the Maxi-K channel for regulating human corporeal smooth muscle tone, and by extension, erectile capacity and function.     

咪达唑仑对交感神经元N-型钙通道电流的影响

目的；通过观察咪达唑仑对交感神经元全细胞N－型钙电流的影响，评价其对交感神经元的抑制作用。方法：用酶消化法获得急性分离的SD大鼠（7－10d）颈上交感神经节细胞，应用膜片钳技术记录不同浓度的咪达唑仑（0．1、0．3、3．0、10、50、100μmol/L）对N－型钙电流的影响。结果：在钳制电位（Vh)-80mV，刺激电压（Vt)-30mV- 10mV条件下，不同浓度的咪达唑仑对N－型钙电流均有抑，且呈浓度依赖性（r=0.964，P＜0．01）。临床相关浓度的咪达唑仑（0．3μmol/L）使钙通道电流峰值下降35％（P＜0．01）。50％钙通道电流峰值受抑制的μmol/L浓度（IC50）约为4．25μmol/L。结论：临床 相关浓度的咪达唑仑对交感神经元全细胞N－型钙电流有明显的抑制作用，提示咪哒唑仑的循环抑 制作用可能与抑制交感神经系统的活动有关。