Adaptations in skeletal muscle capillarity following changes in oxygen supply and changes in oxygen demands

Summary The effects of changes in oxygen supply and oxygen demands on fiber cross-sectional areas, capillary dersities and capillary to fiber ratios were determined in three skeletal muscles of rat. The muscles examined were the vastus lateralis, soleus, and diaphragm. Reduced oxygen supply was produced by subjecting rats to ambient hypoxia, and increased oxygen demands were produced by subjecting rats to low ambient temperatures or treatment with thyroxin. Capillaries were visualized by injecting fluorescent dyes into the circulation. Muscles were quick frozen at resting lengths to preserve normal fiber geometry and were subsequently sectioned on a cryostat. All of the muscles sampled from animals in the experimental groups had elevated capillary densities. However, capillary to fiber ratios were not increased significantly in any muscle, for any experimental condition. Thus, all of the observed differences in capillarity were due to changes in the intrinsic rate of muscle fiber growth. Further, the relations of capillary density and capillary to fiber ratio to fiber area were the same as those obtained during normal maturation, suggesting that capillary growth is closely linked to the intrinsic rate of fiber growth.     

甲心安煎剂对甲状腺素性心脏肥大大鼠心肌胶原含量的影响

目的 探讨甲心安煎剂治疗甲状腺素性心脏肥大的机制。方法将清洁级SD大鼠40只分为4组，即正常组、模型组、甲心安高剂量和低剂量治疗组各10只。正常组与模型组每日灌服纯化水2 mL，高剂量组每日灌服甲心安原液(含生药4 g·mL^-1)，低剂量组灌服甲心安稀释液(将原液加纯化水稀释至含生药2 g·mL^-1)，连续给药10 d。实验第11天取标本检测指标。结果模型组左心室重量及与体重之比均高于正常组(P＜0.01)，心肌胶原含量及 Ⅰ/Ⅲ 胶原比例均较正常组高(P＜0.01)。与之相反，经过甲心安煎剂干预后，治疗组无论低剂量或高剂量，其上述指标均较模型组低(P＜0.01)。结论甲心安煎剂能改善甲状腺素引起的心肌肥厚，降低重构心肌中的胶原含量，并调整优化心肌中 Ⅰ/Ⅲ 胶原比例。     

碘缺乏对BALB/c小鼠促甲状腺激素β剪接变体基因表达的影响

目的 制备碘缺乏小鼠模型,检测促甲状腺激素(TSH)β剪接变体(TSHβ-Ⅴ)是否受循环中甲状腺激素的调节,探讨免疫系统来源的TSHβ-Ⅴ在维持甲状腺自稳态中的作用.方法 选用离乳BALB/c小鼠20只,雌雄各半.小鼠按体质量和性别随机分为2组,每组10只.对照组:饮去离子水,普通饲料喂养;低碘组:饮去离子水,低碘饲料(含碘量20 - 40μg /kg)喂养,每日碘摄入量约为0.25μg/d.3个月后处死小鼠,化学发光免疫分析法(CIA)检测小鼠血清中甲状腺激素和TSH水平,实时定量(RT)-PCR法测定小鼠骨髓、外周血、甲状腺、垂体TSHβ-Ⅴ的表达.结果 低碘组小鼠血清总甲状腺素(TT4)、游离甲状腺素(FT4)、总三碘甲腺原氨酸(TT3)、游离三碘甲腺原氨酸(FT3)[ (0.47±0.70)nmol/L、(2.41±0.28)pmol/L、(0.76±0.08 )nmol/L、(4.01±0.40) pmol/L]显著低于对照组[(55.2±3.68)nmol/L、(32.72±1.02) pmol/L、(1.10±0.06)nmol/L、(5.40±0.38 )pmol/L,t=43.81、86.04、9.81、7.51,P均＜0.01];低碘组小鼠TSH[(35.67±17.39)mU/L]明显高于对照组[(0.24±0.10)mU/L,t =-6.11、,P＜0.001];低碘组小鼠骨髓、外周血TSHβ-Ⅴ mRNA表达水平[(9.62±0.60)、(9.25±0.83)]均低于正常对照组(7.69±0.36、7.11±0.41,t=6.77、5.64,P均＜0.001);低碘组小鼠甲状腺TSHβ-Ⅴ mRNA表达(9.32±0.91)与对照组(9.12±0.62)相比较,差异无统计学意义(t=0.45,P＞0.05);在骨髓、外周血、甲状腺未检出天然型TSHβ;垂体中TSHβ-Ⅴ mRNA和天然型TSHβ表达水平(1.99±0.61、- 7.17±1.78)均高于对照组(5.75±0.98、-1.43±0.51,t=-8.02、- 7.60,P均＜0.01].结论 低碘饮食引发小鼠甲状腺功能低下,抑制骨髓和外周血TSHβ-Ⅴ mRNA的表达,提示免疫系统来源的TSHβ-Ⅴ可能具有比天然型TSHβ更重要的免疫-甲状腺调节作用.     

正常足月新生儿脐血甲状腺激素水平的研究

目的探讨正常足月新生儿脐血甲状腺激素的水平,为临床尽早诊断和治疗新生儿甲状腺功能异常疾病提供依据。方法随机选择在复旦大学附属妇产科医院分娩的193例母亲孕期甲状腺功能正常足月新生儿,断脐后采集脐血,通过化学发光免疫分析法测定各项甲状腺激素水平,并同时采集新生儿3天动脉血检测其甲状腺功能,分析新生儿脐血代替3天动脉血甲状腺激素可行性,从而研究脐血甲状腺激素的参考范围。结果（1）脐血甲状腺激素各项指标参考范围：脐血甲状腺激素为正态分布,TSH（5．375±1．572）、TT3（36．576±8．595）、TT4（8．122±1．019）、FT3（1．657±0．271）、FT4（0．960±0．117）。（2）脐血代替新生儿3天动脉血甲状腺激素具有可行性：脐血和新生儿3天动脉血甲状腺激素五指项标（TSH、TT3、TT4、FT3、FT4）均成正态性分布,新生儿3天动脉血与脐血甲状腺激素均为正相关（P〈O．05）,TSH、TT3、TT4、FT3、FT4的回归方程分别为Y=84．215＋0．067X（P〈0．05）、Y=8．765＋0．457X（P〈0．05）、Y=1．021＋1．245X（P〈0．05）、Y=1．856＋0．272X（P〈0．05）、Y=8．765＋0．457X（P〈0．05）,可以用脐血推算新生儿3天动脉血中的甲状腺激素水平。结论用脐血代替具有创伤性的动脉穿刺血分析甲状腺激素水平,既能为患儿家长所接受,也能尽早发现及干预新生儿甲状腺功能异常疾病。     

大鼠脾虚证与血清甲状腺激素及下丘脑、胸腺细胞核T3受体关系

目的：探讨脾虚证与血清甲状腺激素及下丘脑、胸腺细胞核T3受体的关系。方法：成年SD大鼠32只了随机分为4组（每组8只）：A组（正常组）、B组（脾虚组）、C组（治疗组）、D组（自复组）。采用放射配基分析法,测定各组大鼠血清T3、T4、FT3、FT4、 γ－T3 及下丘脑、胸腺细胞核T3受体的含量。结果：B、D组大鼠血清T3、T4、FT3、FT4含量均较A、C组低,有显差异（P＜0.05或P＜0.01）;各且间血清γ－T3 含量无显性差异;B、D组下丘脑、胸腺细胞T3受体含量较A、C组低,有显差异（P＜0.01）。结论：血清甲状腺激素及下丘脑、胸腺细胞核T3受体的水平降低,可导致甲状腺激素生物效应低下,经由神经内分泌免疫调节环路,削弱免疫功能,这可能是脾虚证的一种重要病机。     

甲状腺激素治疗老年充血性心力衰竭的临床观察

目的:观察老年充血性心力衰竭(CHF)患者甲状腺激素水平及甲状腺激素治疗的效果.方法:将86例老年CHF患者随机分为两组,在常规治疗的基础上,治疗组加用甲状腺片10～20 mg/d,2周为一疗程.结果:治疗组治疗后三碘甲状腺原氨酸(T3)明显上升(P＜0.05);治疗组总有效率高于对照组(χ2=9.53,P＜0.01);心功能显著改善相关,心功能Ⅳ级患者改善更明显(P＜0.05).结论:CHF患者大多数体内甲状腺激素水平降低,适当地补充甲状腺激素对老年 CHF治疗有益.     

黄芪四君汤对脾虚证大鼠甲状腺素及环核苷酸水平的影响

目的观察黄芪四君汤对脾虚证模型大鼠甲状腺激素及环核苷酸水平的影响,探讨该方防治脾虚证的作用机理。方法SD雄性大鼠随机分为3组:正常对照组,脾虚模型组,黄芪四君汤组。采用大黄复制脾虚证动物模型,观察各组动物血清甲状腺素(T4)、三碘甲腺原氨酸(T3)、促甲状腺素(TSH)及血浆环磷酸腺苷(cAMP)、环磷酸鸟苷(cGMP)水平的变化。结果与正常对照组比较,脾虚模型组大鼠血清T3、T4含量下降(P<0.01),血浆cAMP含量及cAMP/cGMP比值均升高(P<0.01)。黄芪四君汤能提高实验性脾虚证大鼠T3、T4水平及脾脏指数、胸腺指数,降低cAMP含量及cAMP/cGMP比值。结论黄芪四君汤能改善脾虚证模型大鼠的脾虚症状,其作用机理与调节甲状腺激素及cAMP、cGMP水平有关。     

New approaches to the treatment of acute renal failure

At present, the clinician is left in a relatively dependent position when encountering a patient with established acute renal failure (ARF). Clearly, interventional therapies that can significantly influence the process of recovery from ARF are limited. Although a variety of manipulations and drugs will protect against the loss of renal function when administered prior to the initiation of a renal insult, the clinician usually encounters a patient after ARF has been established. Thus, pertubations that will protect against the development of ARF or modify the severity of the renal insult are not applicable. Moreover, it is clear that the mortality and morbidity for patients with ARF is unacceptably high. Although a variety of supportive measures such as peritoneal/hemodialysis or continuous arteriovenous hemofiltration are now applicable to patients of almost any size or weight, patients continue to diewith but perhaps notof ARF. This article will review several new agents that act to enhance the restoration of renal function and result in accelerated recovery of both glomerular and tubular function, following an established acute renal insult: adenine nucleotides, thyroxin, and calcium channel blockers.     

甲状腺素对豚鼠耳蜗毛细胞的保护作用

应用耳蜗外淋巴灌流技术、微电极技术及扫描、透射电镜技术，观察先服甲状腺素（10mg)三次后行外淋巴灌流卡那霉素（10^-3g/ml)1小时的豚鼠实验组（T／K）蜗内电位（EP），耳蜗微音电位（CM）和毛细胞的亚微结构变化，并与单纯灌流卡那霉素（10^-3g/ml)的豚鼠对照组（KM）进行比较，发现3组动物EP无明显差异；实验组（T／K）的CM下降较对照组（KM）少，两者有显著差异；实验组动物外毛细胞损伤较对照组动物轻，提示甲状腺素可能直接作用于听毛细胞，减轻卡那霉素对内耳的毒副作用。     

慢性收缩性心力衰竭与正常甲状腺功能病态综合征的临床观察

目的观察慢性心功能不全患者血清甲状腺激素水平的变化,并探讨其临床意义。方法用放射免疫法测定58例心功能Ⅲ～Ⅳ级患者,60例心功能Ⅰ～Ⅱ级患者及62例心功能正常患者血清甲状腺激素（游离三碘甲状腺原氨酸FT3,游离甲状腺素FT4,总三碘甲状腺原氨酸T3,总甲状腺素T4）及促甲状腺素（TSH）水平,并进行比较。结果心功能Ⅲ～Ⅳ级患者血清FT3、T3水平明显低于心功能Ⅰ～Ⅱ级患者和心功能正常患者,差异有统计学意义（P〈0．05）。结论慢性心功能不全患者血清甲状腺素水平对心功能患者病情判断及预后有一定临床参考价值。