一个琥珀酸半醛脱氢酶缺陷症家系ALDH5A1基因的突变检测北大核心CSCD

目的对1个琥珀酸半醛脱氢酶缺陷症家系进行ALDH5A1基因突变分析,为疾病的诊断及遗传咨询提供依据。方法收集患者及其父母外周血,提取基因组DNA,应用PCR扩增产物直接测序法对致病基因ALDH5A1的11个外显子序列及其两侧内含子区域进行分析,以100名健康人为正常对照。结果在患者的ALDH5A1基因上发现第2外显子C．398_399delAA以及第4外显子c．638G〉T（p．R213L）复合杂合突变,家系成员检测证实其中c.398—399delAA突变来自母亲,而c．638G〉T（p．R213L）突变来自父亲。100名健康对照未见上述突变。结论c．398—399delAA和c．638G〉T复合杂合突变是该家系患儿的致病原因,上述突变尚未见报道,丰富了琥珀酸半醛脱氢酶缺陷症致病基因ALDH5A1的突变谱。     

一例琥珀酸半醛脱氢酶缺陷症患儿的基因变异分析CSCD

目的探讨1例琥珀酸半醛脱氢酶缺陷症患儿的遗传学病因。方法采集患儿及其父母的外周血样,提取基因组DNA,用Sanger测序和全外显子组测序对患儿及其父母进行检测,分析变异位点的致病性。结果Sanger测序结果提示患儿携带ALDH5A1基因c.1529C>T(p.S510F)纯合变异,其母亲为杂合型,父亲未检测到此变异。全外显子组测序发现患儿及其父亲均携带ALDH5A1基因片段缺失(chr6:24403265-24566986)。结论ALDH5A1基因c.1529C>T变异及缺失是患儿的致病原因。全外显子组测序能同时检测碱基变异和基因片段缺失,为患儿的诊断和遗传咨询提供依据。     

高分辨率熔解曲线技术在筛查琥珀酸半醛脱氢酶缺陷症致病基因突变中的应用

目的对4例琥珀酸半醛脱氢酶缺陷症(SSADHD)患儿家系进行基因突变分析,在明确突变的基础上建立针对醛脱氢酶5家族成员A1基因(ALDH5A1)中常见致病基因突变位点c.1529C> T(p.S510F)的高分辨率熔解(HRM)曲线快速筛查方法。方法先证者4例SSADHD患儿年龄(5.3±2.2)个月,其中男性3例,女性1例。商品化试剂盒提取4例先证者及其亲属外周血基因组DNA;采用一代测序技术对患者家系的ALDH5A1进行基因突变分析;应用HRM曲线技术随机筛查80例患儿ALDH5A1上c.1529C> T位点突变。结果先证者均有致病基因突变c.1529C> T位点,其中2例为该位点纯合突变,2例杂合携带并伴有其他致病位点的杂合突变。先证者及其家属的HRM分析结果与测序结果一致。随机检测的80例患儿,年龄为(7.5±3.9)岁,其中男性48例,女性32例,均不携带该基因突变。结论推测c.1529C> T位点突变可能是津冀地区SSADHD患儿中ALDH5A1的常见致病基因突变位点,但其在人群中携带频率很低;利用HRM曲线技术可实现对该位点的快速筛查。     

一例琥珀酸半醛脱氢酶缺陷症患儿的基因变异分析

目的:探讨1例琥珀酸半醛脱氢酶缺陷症患儿的遗传学病因。方法:采集患儿及其父母的外周血样,提取基因组DNA,用Sanger测序和全外显子组测序对患儿及其父母进行检测,分析变异位点的致病性。结果:Sanger测序结果提示患儿携带 ALDH5A1基因c.1529C>T(p.S510F)纯合变异,其母亲为杂合型,父...     

成都地区献血人群Jk(a-b-)表型的DNA序列分析

目的 调查成都地区献血人群Jk(a-b-)表型的分子遗传特征.方法 采用聚合酶链反应-序列特异性引物技术对成都地区8名Jk(a-b-)表型献血者了K基因第4~11外显子及其侧翼区域进行扩增,并对产物进行测序分析.结果 8份样本均为第9外显子c.838AA纯合型,含有无效Jkb等位基因.发现4种突变序列:(1)IVS5-1G>A纯合突变、第7外显子c.588 A>G(P.Pr0196Pro)纯合突变;(2)第9外显子c.896G>A(P.Gly299Glu)纯合突变、第7外显子c.588 A>G(P.Pr0196Pro)纯合突变;(3)IVS5-1 G>A杂合突变、第5外显子c.222C>A(P.Asn74Lys)杂合突变、第7外显子c.499A>G(Met167Val)杂合突变、第7外显子c.588 A>G(P.Pro196Pro)纯合突变;(4)IVS5-IG>A杂合突变、第9外显子c.896G>A(P.Gly299Glu)杂合突变、第7外显子c.588 A>G(P.Prol96Pro)纯合突变.结论 IVS5-IG>A突变、第5外显子c.222C>A突变(p.Asn74Lys)和第9外显子c.896G>A突变(P.Gly299Glu)可能是成都地区献血人群Jk(a-b-)表型的分子遗传基础.     

一例Crigler-Najjar综合征Ⅱ型患儿的基因突变分析北大核心CSCD

目的对1例Crigler-Najjar综合征Ⅱ型患儿的尿苷二磷酸葡萄糖醛酸转移酶1A1（UGT1A1）基因进行突变分析,探讨其分子发病机制,为家系的遗传咨询及产前基因诊断提供依据。方法抽取患儿及其父母的外周静脉血提取基因组DNA,应用聚合酶链反应扩增UGT1A1基因的相应片段,经DNA测序法对UGT1A1基因进行突变检测,并随访患儿至3岁6个月。结果患儿为持续高未结合胆红素血症,DNA测序结果显示患儿UGT1A1基因的第1外显子存在c．610A〉G（p．Met 204 Val）杂合突变,第4外显子存在c．1091C〉T（p．Pro 364 Leu）杂合错义突变,患儿为UGT1A1基因复合突变杂合子。患儿父亲UGT1A1基因的第4外显子存在C．1091C〉T（p．Pro 364 Leu）的杂合错义突变,患儿母亲UGT1A1基因的第1外显子存在c．610A〉G（p．Met204 Val）杂合错义突变。结论UGT1A1基因第1外显子c．610A〉G、第4外显子c．1091C〉A复合杂合突变为该患儿的发病原因,为其家系的遗传咨询和产前基因诊断提供了依据。     

复合杂合性蛋白C基因突变导致的遗传性蛋白C缺陷症家系分析

目的 对1个遗传性蛋白C(proteinC,PC)缺陷症家系进行蛋白 C基因(protein C gene,PROC)突变检测,探讨其分子发病机制.方法 通过检测先证者及其家系成员(共4代15人)血浆蛋白C活性(protein C activity,PC∶A)、蛋白C抗原含量(protein C antigen,PC∶Ag)及其他凝血指标进行表型分析;用PCR法扩增先证者PROC的9个外显子及其侧翼序列,PCR产物纯化后测序,发现突变位点则反向测序予以证实;针对先证者的突变位点,对其家系成员进行相应基因突变检测.结果 先证者PC∶ A和PC∶Ag明显降低,分别为26％和18.60％,家系中其他成员中有7人PC∶A降低,6人PC∶Ag降低.先证者的PROC第7外显子存在g.6128T＞G杂合错义突变导致p.Phe139Val,第9外显子存在g.8478G＞C杂合错义突变导致p.Asp255His;其祖母、父亲、三姑和四姑均存在g.6128T＞G杂合突变,母亲、二舅、妹妹和儿子均存在g.8478G＞C杂合突变.存在g.8478G＞C突变的成员PC∶A下降明显.结论 先证者PROCg.6128T＞G和g.8478G＞C突变分别来自其父系家族和母系家族,该复合杂合错义突变是导致遗传性PC缺陷症的分子基础.     

遗传性出血性毛细血管扩张症基因突变分析

目的 分析遗传性出血性毛细血管扩张症(hereditary hemorrhagic telangiectasia,HHT)家系ENG、ACVEL1和SMAD4基因突变.方法 收集4个HHT家系临床资料并分析其临床特点,应用直接测序和多重连接探针扩增技术对11例临床确诊及可疑患者的ENG、ACVRL1和SMAD4基因进行突变分析,将结果与HHT基因突变数据库进行对比.结果 家系2先证者及2个妹妹的ENG基因发生了第2外显子c.207G＞A(p.L69L)同义突变、第8外显子c.1004A＞T(p.Q335L)错义突变、ACVRL1基因第7外显子c.817C＞T(L273L)同义突变;家系3先证者及其母亲和弟的ENG基因发生了第8外显子c.1004A＞T(p.Q335L)突变;也检测到家系4先证者及其兄的ENG基因第8外显子c.1004A＞T(p.Q335L)突变.家系1先证者及其他HHT患者,未检测到基因突变.其中ENG基因第8外显子c.1004A＞ T(p.335Q＞L)为新突变,在200名正常对照中也未检测到该突变.结论 HHT具有遗传异质性,ENG基因第8外显子c.1004A＞T(p.Q335L)为HHT新的致病突变.     

一例火棉胶样儿TGM1基因的突变分析CSCD

目的对1例维吾尔族火棉胶样患儿的TGM1基因进行突变分析,寻找其病因。方法对患儿及其父母进行常规染色体G显带核型分析,应用芯片高通量测序方法对患儿进行鱼鳞病及鱼鳞病样皮肤病25个相关基因的检测。 结果染色体G显带核型分析结果显示患儿及父母核型均正常;芯片捕获高通量测序检测出患儿TGM1基因的c.919C〉T（p.Arg307Trp）和c.856C〉T（p.Arg286Trp）复合杂合突变;前者为已知致病突变,后者为临床意义未明突变。Sanger测序验证,患儿父亲携带TGM1基因c.856C〉T（p.Arg286Trp）杂合突变,未检出患儿母亲TGM1基因c.919C〉T、c.856C〉T的位点突变。结论TGM1基因c.919C〉T和c.856C〉T复合杂合突变可能是患儿的致病原因。     

一个复合杂合变异导致的遗传性凝血因子Ⅻ缺陷症家系分析

目的检测1个遗传性凝血因子Ⅻ(coagulation factorⅫ,FⅫ)缺陷症家系的基因变异,探讨其分子致病机制。方法用DNA直接测序法对F12基因进行变异分析;在野生型pIRES2-EGFP/FⅫ表达质粒基础上,构建变异型FⅫ表达质粒,Polyfect转染试剂瞬时转染293T细胞,分别测定上清液中FⅫ活性(FⅫactivity,FⅫ∶C)和FⅫ抗原(FⅫantigen,FⅫ∶Ag),测定细胞裂解液中FⅫ∶Ag,并用Western印迹进行验证。结果先证者F12基因第1外显子启动子区为46TT基因型,在第13和14外显子存在g.8489G>A(p.Glu502Lys)和g.8699G>C(p.Gly542Ser)复合杂合变异。瞬时转染结果显示,FⅫp.Glu502Lys变异体蛋白上清液中FⅫ∶C和FⅫ∶Ag分别为野生型的28%和24%,细胞裂解液中FⅫ∶Ag为野生型的39%;FⅫp.Gly542Ser变异体蛋白上清液中的FⅫ∶C和FⅫ∶Ag分别为野生型的32%和17%,细胞裂解液中FⅫ∶Ag为野生型的59%。结论先证者F12基因型46TT,p.Glu502Lys和p.Gly542Ser复合杂合变异导致其FⅫ水平极度降低;体外表达实验证实变异蛋白p.Glu502Lys和p.Gly542Ser存在合成和分泌障碍。     

DIMINISHING PURKINJE CELL POPULATIONS IN THE CEREBELLA OF AGING HETEROZYGOUS PURKINJE CELL DEGENERATION BUT NOT HETEROZYGOUS NERVOUS MICE

Mice homozygous for the recessive, cerebellar affected mutations nervous and Purkinje cell degeneration display an almost complete loss of Purkinje cells during their first two postnatal months. We have recently shown a progressive and age-related loss of Purkinje cells in mutant mice heterozygous for mutations apparently recessive, such as staggerer and reeler , and have thus chosen to investigate whether a similar Purkinje cell loss occurred with aging in +/ nr and +/ pcd heterozygous mice. Purkinje cells were counted on serial sections heterozygous mice. Purkinje cells were counted on serial sections stained with thionin obtained from 17-month-old male and female heterozygous mice and their respective wild-type controls. In the case of the +/ nr wild-type mice, no difference in cell counts was observed. However, +/ pcd mice had significantly fewer (?18%) Purkinje cells (143.700±5.400) than control wild-types (175.100±2.300); p<0.0001) at 17 months. These results extend our previous findings and further support the idea that apparently recessive neurological mutations may exert, at the heterozygous state, a deleterious effect upon Purkinje cells during the aging process.     

尿素酶预处理-气相色谱-质谱法诊断琥珀酸半醛脱氢酶缺陷病

本文探讨琥珀酸半醛脱氢酶(succinic semialdehyde dehydrogenase,SSADH)缺陷病各尿液标志物的气相色谱-质谱法(Gas Chromatography-Mass Spectrometry,GC-MS)分析特征。收集SSADH患儿的尿液标本,经去尿素、加内标(正十七酸)、除蛋白、真空干燥处理,残余物进行三甲基硅烷化衍生后进样行GC-MS法分析。尿液中可检测到明显的4-羟基丁酸、2,4-二羟基丁酸、3,4-二羟基丁酸和4,5-二羟基己酸信号。在TIC图上,其绝对保留时间(相对保留时间)分别是6．32min(0．434),7．80min(0．536),7．94min(0．546),8．80min,8．90min(0．605,0．612)。在质谱图上,其特征离子(m／z,TMS)分别是M-15(233,2),M-15(321,3),M-15(321,3),M-15(349,3)。GC-MS法分离鉴定尿液代谢成分,可作为诊断该病的一种可靠手段。     

Histochemical mapping of succinic dehydrogenase and cytochrome oxidase in the spinal cord, medulla oblongata and cerebellum of squirrel monkey (Saimiri sciureus)

Summary The distribution of succinic dehydrogenase (SDA) and cytochrome oxidase (Cy. O) in serial sections of the cervical region of the spinal cord and the medulla oblongata, arranged caudo-cranially, has been described. The motor cranial nerve nuclei exhibit strong SDA and Cy. O activity in the neurons and neuropil. The nuclei gracilis, cuneatus, olivaris inferior, cochlearis and vestibularis likewise show strong enzyme activity. Nucleus intercalatus and nucleus tractus solitarius, however, show weak and moderate enzyme activity respectively. The lateral part of formatio reticularis myelencephali shows less SDA and Cy. O compared to the medial part, which shows some accumulation of these enzymes in the neuropil.The neuropil of the molecular layer of cerebellar cortex and the perikarya and dendrites of the Purkinje cells show strong SDA and Cy. O activity. The granular layer exhibits stronger SDA and Cy. O in the synaptic glomeruli. The cerebellar nuclei possess stronger enzyme activity in the neurons and dendritic branches, compared to mild activity in the neuropil.Abbreviations AB Nucleus ambiguus - AP Area postrema - Cb Cerebellum - Cn Nucleus cuneatus medialis - CnL Nucleus euneatus lateralis - CRF Corpus restiforme - D Cell group D of meesen and Olszewski (1949) - DPy Decussatio pyramidum - DV Nucleus dorsalis n. vagi - F Cell group P of Meesen and Olszewski (1949) - FC Puniculus cuneatus - FG Funiculus gracilis - FLM Fasciculus longitudinalis medialis - FRM Formatio reticularis myelencephali - G Nucleus gracilis - Gr Granular layer of cerebellar cortex - I Nucleus intercalatus - Lcb Lingula cerebelli - MoL Molecular layer of cerebellar cortex - NC Nucleus cochlearis - NCD Nucleus cochlearis dorsalis - NCV Nucleus cochlearis ventralis - ND Nucleus dentatus - NE Nucleus emboliformis - NF Nucleus fastigii - NFL Nerve fiber layer - NG Nucleus globosus - NR Nucleus raphes - NSV Nucleus tractus spinalis n. trigemini - NTS Nucleus tractus solitarius - NVI Nucleus n. abducentis - NVII Nucleus n. facialis - NXII Nucleus n. hypoglossi - OI Nucleus olivaris inferior - OIm Nucleus olivaris inferior, accessorius medialis - OIp Nucleus olivaris inferior, principalis - P Layer of Purkinje cells - Pp Nucleus praepositus - Py Tractus pyramidalis - RG Nucleus reticularis gigantocellularis - RL Nucleus reticularis lateralis myelencephali - RPM Nucleus reticularis paramedianus myelencephali - SGD Nucleus substantiae griseae dorsalis - SGL Nucleus substantiae griseae lateralis - SGV Nucleus substantiae griseae ventralis - TCV Tractus corticospinalis ventralis - TS Tractus solitarius - TSC Tractus spinocerebellaris - VI Nucleus vestibularis inferior - VL Nucleus vestibularis lateralis - VM Nucleus vestibularis medialis - VS Nucleus vestibularis superior - IV Ventriculus quartus     

切断下丘脑漏斗后对主动脉壁的影响

目的 探讨下丘脑对血管调控的路径。方法 将１８只Ｗｉｓｔａｒ大鼠分成实验组和对照组，实验组１２只，对照组６只。实验组行手术切断漏斗，对照组行手术暴露但不切断漏斗，手术后２ｈ，两组动物移至同一条件下饲养，存活３０ｄ后用１％多聚甲醛＋１．２５％戊二醛液从心脏灌流固定，取主动脉作光、电镜观察。结果 切断下丘脑与垂体的联系后，血管内皮细胞变性，细胞核肿胀，内皮下层增厚并出现许多大小不一的空泡，肌内皮连结受     

Histochemical mapping of succinic dehydrogenase and cytochrome oxidase in the pons and mesencephalon of squirrel monkey (Saimiri sciureus)

Summary The distribution of succinic dehydrogenase (SDA) and cytochrome oxidase (Cy. O) has been investigated in a series of sections through the pons and mesencephalon of the squirrel monkey brain. The localization of the two enzymes is very similar in the various regions and shows only slight differences. The epiphysis, however, shows moderately strong SDA and very mild Cy. O activity. Particularly strong SDA and Cy. O activity has been observed in the cell bodies of the various cranial nerve nuclei, nucleus colliculi inferioris, colliculi superioris, nuclei griseum pontis, reticularis tegmenti pontis, lemnisci lateralis pars dorsalis, geniculatum laterale and mediale, and pulvinaris. The enzyme content of the neurons and cell bodies is generally stronger compared to the neuropil which often occurs in smooth, loose, compact and reticulated forms. Any special relationship between the neurons and neuropil with regard to their enzyme content has, however, not been observed. The cranial nerves, and fibers of the brachium conjunctivum, corpus callosum, and fornix show very mild enzyme activity except those of the trapezoid complex which show moderate enzyme activity.Abbreviations Ann Nucleus annularis - APT Area praetectalis - AS Aquaeductus Sylvii - BC Brachium conjunctivum - BCI Brachium colliculi inferioris - BCS Brachium colliouli superioris - BP Brachium pontis - Cb Cerebellum - CC Corpus callosum - CCI Commissura colliculi inferioris - CCS Commissura colliculi superioris - Cd Nucleus caudatus - CHD Commissura hippocampi —parsdorsalis - CoI Colliculus inferior - CoP Commissura posterior - CoR Corona radiata - CoS Colliculus superior - CPf Cortex piriformis - CR Cortex retrosplenialis - DBC Decussatio brachii conjunctivi - DG Nucleus dorsalis tegmentalis(Gudden) - DR Nucleus dorsalis raphes - EP Epiphysis - F Fornix - FH Fimbria hippocampi - FLM Fasciculus longitudinalis medialis - FRPC Formatio reticularis pontis, parscaudalis - FRPO Formatio reticularis pontis, parsoralis - FRTM Formatio reticularis tegmentimesencephali - GC Substantia grisea centralis - GCd Substantia grisea centralis, parsdorsalis - GCv Substantia grisea centralis, parsventralis - GL Corpus geniculatum laterale - GM Corpus geniculatum mediate - GPO Griseum pontis - Hipp Hippocampus - HL Nucleus habenulae lateralis - HM Nucleus habenulae medialis - IP Nucleus interpeduncularis - LC Nucleus locus coeruleus - LCb Lingula cerebelli - Lim Nucleus limitans thalami - LL Lemniscus lateralis - LLD Nucleus lemnisci lateralis —parsdorsalis - LM Lemniscus medialis - LP Nucleus lateralis posterior thalami - MD Nucleus medialis dorsalis thalami - Mv Nucleus motorius n. trigemini - NCI Nucleus colliculi inferioris - NCS Nucleus centralis superior tegmenti - NCT Nucleus trapezoideum - NMv Nucleus tractus mesencephalicus n.trigemini - NR Nucleus ruber - NST Nucleus supratrochlearis - NSv Nucleus tractus spinalis n. trigemini - NiiiC Nucleus centralis n. oculomotorii - NiiiD Nucleus n. oculomotorii — pars dor-salis - NiiiV Nucleus n. oculomotorii — pars ven-tralis - Niv Nucleus n. troehlearis - nvm Nervus trigeminus, portio major - niv Nervus trochlearis - nvi Nervus abducens - OS Nucleus olivaris superior - P Nucleus posterior thalami - PbL Nucleus parabrachialis lateralis - PbM Nucleus parabrachialis medialis - PC Pedunculus cerebri - Pg Nucleus parabigeminalis - PUI Nucleus pulvinaris inferior thalami - PUL Nucleus pulvinaris lateralis thalami - PUM Nucleus pulvinaris medialis thalami - Py Tractus pyramidalis - Pv Nucleus principalis n. trigemini - R Nucleus reticularis thalami - RTP Nucleus reticularis tegmenti pontis - SNc Substantia nigra — pars compacta - SNd Substantia nigra — pars diffusa - Sub Subiculum - TCT Tractus corticotectalis - VR Nucleus ventralis raphes - III Ventriculus tertius - IV Ventriculus quartus     

阿霉素性心肌病之心肌线粒体酶的细胞化学研究

阿霉素性心肌病之心肌线粒体SDH和CCO的细胞化学观察发现,多数线粒体的酶活性较弱,少数较强或中等,并与ADR的累积用量和心肌损伤程度有关。作者认为SDH和CCO活性降低,线粒体能量代谢障碍在ADR引起心肌病的过程中起着重要作用。     

Histochemical analysis of muscle fiber types of rat superior rectus extraocular muscle

Extraocular muscles (EOMs) represent a distinctive class among mammalian skeletal muscles in exhibiting unique anatomical and physiological properties. To gain insight into the basis for the unique structural/functional diversity of EOM fiber types and to explain their high fatigue resistance, rat superior rectus muscle (SRM) was studied using histochemical techniques. Muscle fibers were typed with regard to their oxidative and glycolytic profiles generated from succinic dehydrogenase (SDH) and phosphorylase activities in combination with their morphologic characteristics. Superior rectus muscle is organized into two layers, a central global layer (GL) of mainly large diameter fibers and an outer C-shaped orbital layer (OL) of principally small diameter fibers. Five muscle fiber types were recognized within the SRM: I, II, III, IV and V. In the global layer, four muscle fiber types were identified: type I (18.25±0.96 μm; 32%) showed intermediate SDH (coarse type) and high phosphorylase activity. Type II fibers (14.45±0.82 μm; 22%) exhibited high SDH (fine type) and intermediate phosphorylase activity. Low SDH (granular type) and high phosphorylase activity were demonstrated by type III fibers (22.65±1.73 μm; 36%). Type IV fibers (26.24±1.32 μm; 10%) were recognized by their low oxidative and glycolytic reactions. In the orbital region, only three muscle fiber types were recognized; fiber types I and II were found to compose approximately two-thirds of the layer. The third orbital fiber type (type V, 10.05±0.99 μm) exhibited low SDH and low phosphorylase profiles. In this paper, the functional significance of the histochemical characteristics of the EOM fiber types is discussed.     

Effects of endurance training on myosin heavy-chain isoforms and enzyme activity in the rat diaphragm

We investigated the effects of endurance training (20 m/min, 60 min/day, 5 days/week) on myosin heavy-chain (MHC) isoforms and succinic dehydrogenase (SDH) activity in rat crural and costal diaphragms, and plantaris muscles. Although the 4-week endurance training produced significant (P<0.05) increases, both in SDH activity and the percentage of isoform HCIIa in the plantaris of the trained rat compared with the sedentary control rat, these alterations did not occur in either the crural or costal diaphragms. After 10 weeks of endurance training, trained animals had significantly (P<0.05) higher SDH activity in the costal diaphragm and the plantaris. Moreover, a significant (P<0.05) decrease occurred in the percentage of HCIIb in the costal diaphragm, and a significant (P<0.01) decrease in the percentage of HCIIb concomitant with a significant (P<0.05) increase of HCIIa resulted in the plantaris. However, the crural diaphragm did not show any significant changes after 10 weeks of endurance training. These results indicate that endurance training induces an alteration in the expression of an MHC phenotype, in addition to causing an increase in oxidative enzyme activity. However, the alterations in response to endurance training are apparently not uniform, varying between regions and/or kinds of muscles.