大鼠急性心肌梗死后的心肌细胞凋亡和凋亡相关基因表达的变化

目的： 观察大鼠急性心肌梗死（AMI）后的心肌细胞凋亡和caspase-3、Bcl-2和Bax表达的变化。 方法: 105只雌性SD大鼠，随机取78只结扎左冠状动脉建立AMI模型，24 h存活43只作为心肌梗死组（MI组）；另27只设为假手术组（S组）；两组再按观察时点随机分为48 h和4周两亚组，即：MI 48 h（n=11）和MI 4周（n=13）组，S48 h（n=10）和S4周（n=10）组。末端脱氧核糖核苷酸转移酶介导的dUTP切口末端标记技术（TUNEL）和DNA凝胶电泳检测心肌细胞凋亡。免疫组化方法和Western blotting检测caspase-3、Bcl-2和Bax的表达。 结果： MI 48 h组动脉收缩压（SBP）、舒张压（DBP）、平均压（MAP）、左心室收缩压（LVSP）和左心室内压最大上升下降速率（±dp/dt）均显著低于S组（P<0.05, P<0.01），左心室舒张末压（LVEDP）显著高于S组（P<0.05）；MI 4周组除SBP、DBP和MAP无显著差异（均P>0.05）外，上述其它指标的变化与MI 48 h组相同，且LVEDP升高更为显著（P<0.01）；MI 48 h和4周两组梗死/疤痕区、梗死边缘区和非梗死区的心肌细胞凋亡指数均显著升高P<0.05,P<0.01），心肌细胞中“凋亡执行因子”caspase-3和“凋亡促进基因”Bax的表达亦均显著增高（P<0.05,P<0.01），而“凋亡抑制基因”Bcl-2仅在MI 48 h组梗死区心肌细胞中表达增加，“抑制凋亡复合基因”Bcl-2/Bax的比值仅在MI 48 h组降低。 结论： 大鼠AMI后，梗死区及其边缘区和非梗死区均有心肌细胞凋亡发生，伴“凋亡执行因子”caspase-3和“凋亡促进基因”Bax的表达增加；AMI早期，“凋亡抑制基因”Bcl-2在梗死区表达增加，但“抑制凋亡复合基因”Bcl-2/Bax的比值下降。     

短链酰基辅酶A脱氢酶在大鼠生理性和病理性心肌肥大中的作用

 目的：研究短链酰基辅酶A脱氢酶(short-chain acyl-CoA dehydrogenase, SCAD)在大鼠生理性和病理性心肌肥大中的变化,探讨其与心肌肥大之间的关系。方法：以自发性高血压大鼠作为病理性心肌肥大模型,游泳运动训练性大鼠作为生理性心肌肥大模型。检测大鼠的血压、左室重量指数、血清和心肌游离脂肪酸含量、SCAD mRNA、蛋白表达及其酶活性的变化,采用超声心动图观察心脏的结构及功能。结果：与对照组比较,运动组大鼠出现了明显的离心性肥大,心肌收缩功能增强;而高血压组大鼠呈现出明显的向心性肥大,心肌收缩功能减退。与对照组比较,运动组和高血压组大鼠的左室重量指数均明显增高,但两组间比较无显著差异,二者发生了相同程度的心肌肥大。与对照组比较,运动组大鼠左心室SCAD mRNA和蛋白表达均明显上调,酶活性增高,血清和心肌游离脂肪酸含量明显减少;而自发性高血压大鼠左心室SCAD mRNA和蛋白表达均明显下调,酶活性下降,血清和心肌游离脂肪酸含量明显增多。结论：SCAD在生理性和病理性心肌肥大中呈现出不一致的变化趋势,可能作为区别2种不同心肌肥大的分子标志物以及病理性心肌肥大的潜在治疗靶点。     

cDNA芯片法筛选压力负荷型心肌肥厚相关基因

应用cDNA芯片技术筛选腹主动脉绑扎后4周大鼠的压力负荷型心肌肥厚相关基因。在反转录来自假手术及腹主动脉绑扎（4周）的大鼠心肌细胞RNA的过程中，用α－^33P-dATP进行探针的标记。然后将探针与微阵列尼龙腹杂交，高严谨度洗涤后分析杂交图谱。通过所获某种特定基因信号的相对强度来比较其对照及腹主动脉绑扎的大鼠心肌组织中表达水平的差异。结果显示有235个基因片段在两组之间信号差别在3倍以上，其中5倍以上差异的基因有55个，而在这55个基因中有26个基因功能未知。所得差异自然包括TGFβ受体III，raf,ARF,clk2等重要的信号传导分子与心肌肥厚的发生密切相关。     

Exercise preconditioning attenuates pressure overload-induced pathological cardiac hypertrophy

Pathological cardiac hypertrophy, a common response of the heart to a variety of cardiovascular diseases, is typically associated with myocytes remodeling and fibrotic replacement, cardiac dysfunction. Exercise preconditioning (EP) increases the myocardial mechanical load and enhances tolerance of cardiac ischemia-reperfusion injury (IRI), however, is less reported in pathological cardiac hypertrophy. To determine the effect of EP in pathological cardiac hypertrophy, Male 10-wk-old Sprague-Dawley rats (n=30) were subjected to 4 weeks of EP followed by 4-8 weeks of pressure overload (transverse aortic constriction, TAC) to induce pathological remodeling. TAC in untrained controls (n=30) led to pathological cardiac hypertrophy, depressed systolic function. We observed that left ventricular wall thickness in end diastole, heart size, heart weight-to-body weight ratio, heart weight-to-tibia length ratio, cross-sectional area of cardiomyocytes and the reactivation of fetal genes (atrial natriuretic peptide and brain natriuretic peptide) were markedly increased, meanwhile left ventricular internal dimension at end-diastole, systolic function were significantly decreased by TAC at 4 wks after operation (P < 0.01), all of which were effectively inhibited by EP treatment (P < 0.05), but the differences of these parameters were decreased at 8 wks after operation. Furthermore, EP treatment inhibited degradation of IκBα, and decreased NF-κB p65 subunit levels in the nuclear fraction, and then reduced IL2 levels in the myocardium of rats subject to TAC. EP can effectively attenuate pathological cardiac hypertrophic responses induced by TAC possibly through inhibition of degradation of IκB and blockade of the NF-κB signaling pathway in the early stage of pathological cardiac hypertrophy.     

Exercise-induced physiological hypertrophy initiates activation of cardiac progenitor cells

Objective: Physiological hypertrophy is featured by the hypertrophy of pre-existing cardiomyocytes and the formation of new cardiomyocytes. C-kit positive cardiac progenitor cells increased their numbers in exercise-induced physiological hypertrophy. However, the participation of Sca-1 positive cells in the physiological adaptation of the heart to exercise training is unclear. Methods: Physiological hypertrophy was induced by swimming and the mRNA levels of GATA binding protein 4 (GATA4), atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), endogenous hepatocyte growth factor (HGF), and insulin like growth factor-1 (IGF-1) from the whole heart were determined by real-time polymerase chain reactions (RT-PCRs) analysis. Immunofluorescent staining was used to compare the number of C-kit and Sca-1 positive cardiac progenitor cells. In addition, mRNA levels of C-kit and Sca-1 in left ventricle (LV), right ventricle (RV), and outflow tract (OFT) were determined in mice swimming for 7, 14, and 21 days by RT-PCRs. Results: The ratio of heart weight (HW) to body weight and HW to tibia length and the mRNA level of GATA4 were increased while mRNA levels of ANP and BNP remained unchanged. C-kit and Sca-1 positive cardiac progenitor cells were activated by swimming training. An increased endogenous production of HGF and IGF was observed at least at the mRNA level. Swimming induced a significant up-regulation of C-kit in LV of mice swimming for 1, 2 and 3 weeks and in RV of mice swimming for 3 weeks. Sca-1 positive cardiac progenitor cells were increased in LV and OFT in mice swimming for 3 weeks. Conclusion: This study presents that swimming-induced physiological hypertrophy initiates activation of cardiac progenitor cells.     

大鼠压力负荷型心肌肥厚相关基因片段分离和鉴定

本实验基于心甩肥厚过程中基因表达所发生的变化,采用ＣＤＮＡ差减杂交法分离其中存在表达差异的基因片段,在三个不同时期的六组材料中共分离出三十六修养异性基因片段,其中以心肌组织作为材料分离出二十四个片段,以灌流分离的心肌细胞作为材料的十二个片段。杂交结果显示它们在心肌肥厚组和对照组中确定存在表达差异 。     

高强度间歇运动对自发性高血压模型大鼠病理性心脏肥大的影响及机制

文题释义：高强度间歇运动：是一种相对于中低强度持续有氧运动的训练模式,即反复多次以高强度(>80%最大运动能力)持续数秒到数分钟的训练,且每2次练习之间安排不完全恢复的训练方法。 心脏肥大：是由于心肌受到病理性(如高血压等)或生理性(如长期训练)刺激而发生的代偿性反应,表现为心脏质量和体积增加,相应的分为病理性和生理性心脏肥大2种类型。 背景：规律运动具有健康促进效应,中低强度持续有氧运动已成为高血压等慢性病患者一级和二级预防的重要策略,然而高强度间歇运动的效果尚存在争议。 目的：观察高强度间歇运动对自发性高血压大鼠病理性心脏肥大的作用并探讨其可能机制。 方法：30只雄性自发性高血压大鼠随机分为对照组和运动组,同时将15只Wistar-Kyoto大鼠作为正常血压组。正常血压组和对照组大鼠保持安静状态,运动组进行8周高强度间歇运动。实验后利用无创血压仪测定血压,超声心动术检测心脏结构与功能,苏木精-伊红染色获取心肌细胞横截面积,RT-PCR法检测胚胎基因——心房钠尿肽和脑钠尿肽的mRNA表达量,Western blot法检测PI3-K、Akt、CnAβ和NFATc3的蛋白表达量。 结果与结论：①与正常血压组比较,对照组血压升高(P < 0.05),左心室出现向心性肥大(心腔缩窄、室壁增厚、心肌细胞横截面积升高),心功能下降(P < 0.05),脑钠尿肽mRNA表达上调(P < 0.05),CnAβ蛋白表达量升高(P < 0.05)、p-NFATc3/t-NFATc3比值降低(P < 0.05),PI3-K(p110α)蛋白和p-Akt/t-Akt比值无显著变化(P > 0.05);②与对照组比较,运动组收缩压下降(P < 0.05),心脏发生离心性肥大(心腔扩张),心功能升高(P < 0.05),脑钠尿肽mRNA表达下调(P < 0.05),PI3-K(p110α)蛋白和p-Akt/t-Akt比值升高(P < 0.05),CnAβ蛋白以及p-NFATc3/t-NFATc3比值无显著变化(P > 0.05);③结果表明,8周高强度间歇运动激活PI3-K/Akt信号转导途径诱导自发性高血压大鼠由病理性心脏肥大向生理性肥大转变并改善心功能,但并未对Cn/NFAT途径产生抑制效应。 ORCID: 0000-0001-8744-2423(袁国强);0000-0001-5039-6128(彭朋) 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

运动性心脏肥大：AT1受体、细胞自噬和miRNAs的调节

As a mechanical and exogenous stimulus, exercise training induces cardiac physiological hypertrophy, and the cardiac structure is changed slowly, steadily and coordinately. Simultaneously, energy metabolism and function of the cardiac muscle are also improved. These are positive adaptations in the heart when experiencing endurance exercise training. Recently, angiotensin Ⅱ type 1 (AT1) receptor, autophagy and miRNAs are all considered as important regulators to cardiac hypertrophy induced by exercise training at different molecular levels. Fully understanding the relations and the important role of AT1 receptor, autophagy and miRNAs in cardiac physiological hypertrophy will further enrich the signaling pathway of cardiac hypertrophy induced by exercise training.     

大鼠心肌缺血预适应对I/R心肌细胞凋亡及bcl-2表达的影响

目的:对缺血预适应(IP)第一保护窗对大鼠缺血再灌注(I/R)心肌细胞凋亡和凋亡抑制基因bcl-2表达的影响进行研究。方法:采用TUNEL法、免疫组化和原位杂交方法测定大鼠缺血再灌注心肌细胞凋亡和bcl-2的表达。结果:①IP+I/R_3h组TUNEL法阳性心肌细胞核数量及阳性心肌细胞核占总心肌细胞核数的百分比均明显少于I/R_3h组(P＜0.05,P＜0.01);②IP+I/R_3h组表达bcl-2蛋白阳性的心肌细胞数及阳性心肌细胞占心肌细胞总数的百分比均明显高于I/R_3h组(P＜0.01);IP+I/R_1h组表达bcl-2mRNA阳性的心肌细胞数及阳性心肌细胞占心肌细胞总数的百分比均明显高于I/R_1h组(P＜0.01)。结论:①大鼠心肌IP第一保护窗能够显著减少I/R心肌细胞凋亡;②IP通过上调凋亡抑制基因bcl-2基因表达可能是其减少I/R心肌细胞凋亡的机制之一。     

乳腺癌细胞凋亡、增殖与相关基因表达、突变的关系

目的:研究乳腺癌细胞凋亡、细胞增殖及相关基因表达、突变的关系,为乳腺癌细胞凋亡、细胞增殖失衡的基因调控机制提供依据。方法:分别应用TUNEL法、免疫组化S-P法和PCR-SSCP法检测54例乳腺癌标本凋亡指数(AI)和增殖指数(MI),Bcl-2、p53、c-erbB-2、PCNA、Ki67、TopoⅡ蛋白表达和p53基因突变。结果:54例乳腺癌AI平均9.40±3.78,MI平均5.96±2.36,AI与MI呈显著正相关(r=0.46,P＜0.01)。Bcl-2、PCNA、Ki67、TopoⅡ表达与AI、MI均呈显著正相关(P＜0.01)。p53表达、c-erbB-2表达、p53突变与MI呈显著正相关(P＜0.01)。p53基因突变类型与AI呈显著相关(P＜0.05)。结论:乳腺癌细胞凋亡、增殖失衡与相关基因异常表达、突变有关。     

肾上腺素能受体与心肌肥大的研究进展

心肌肥大是一种较缓慢而有力的代偿形式,然而它不是无限度的,心肌肥大最终将引起心室功能异常而导致心力衰竭,这往往是心血管疾病患者的主要死因之一。肾上腺素能受体(adrenergic receptor,AR)是介导儿茶酚胺作用的一类组织受体,研究表明AR与心肌肥大和心力衰竭的发生密切相关。因此,本文就几种AR与心肌肥大近年的研究进展进行综述,以便更好的了解心肌肥大的发生机理。     

Relation of Cardiotrophin-1 (CT-1) and cardiac transcription factor GATA4 expression in rat's cardiac myocytes hypertrophy and apoptosis

The aim of this study was to evaluate the role of GATA4 in hypertrophy and survival functions of CT-1 in the heart, and to apply chemical inhibitor strategies to assess a possible interaction of signaling pathways involved in these processes. Expression of GATA4 was determined at the mRNA expression (polymerase chain reaction, PCR) and protein binding activity (electrophoretic mobility shift assays, EMSAs) levels. Myocardial apoptosis was detected using the in-situ terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method. Parthenolide (an inhibitor to STAT3) and U0126 (an MEK inhibitor to block ERK1/2) were used to assess a possible interaction of signaling pathways involved in the processes. The results showed that CT-1 had a significant role in the expression of GATA4 mRNA and binding activity of cardiomyocytes. The stronger expression of GATA4 mRNA stimulated by CT-1 was essentially mediated by STAT3, and was negatively regulated by ERK1/2. The intercross relationship between STAT3 and ERK1/2 might assist CT-1 in cardiac hypertrophy. At the same time, CT-1 had its effect on anti-apoptosis and survival of cardiac myocytes. During this process, GATA4 expression showed a negative relationship with myocardial apoptosis. Obviously, STAT3 cannot affect the anti-apoptotic process of CT-1, but obstruction of ERK signaling pathway can inhibit the CT-1 anti-apoptotic effect significantly. Our data suggest that CT-1 can affect the expression of GATA4 mRNA and the binding activity of cardiac myocytes. GATA4 plays an important role in the hypertrophic effect of CT-1, in which STAT3 plays a primary role. The regulation of CT-1 on the anti-apoptotic process is mediated partly by GATA4, and can be inhibited by obstructing the ERK signaling pathway.     

Analysis of apoptosis and expression of genes related to apoptosis in cultures of follicles derived from vitrified and non-vitrified ovaries

The aim of this study was to evaluate the incidence of apoptosisafter in vitro culture of isolated follicles derived from vitrifiedand non-vitrified ovaries. Mouse ovaries were vitrified andtheir pre-antral follicles were mechanically isolated and culturedfor 10 days. Growth and survival rates of the follicles wereassessed during the culture period and the ultrastructure ofthe follicles was studied. The expression of p53, Bcl-2, Bax,Fas, FasL and survivin were analyzed by real-time RT–PCRin different follicular developmental stages. The percentagesof apoptotic and necrotic cells were determined using a fluorescein-activatedcell sorting (FACS) technique. There were no differences betweenthe growth and survival rates of follicles in the vitrifiedand non-vitrified groups. All of the evaluated genes were expressedin the pre-antral, large pre-antral and antral follicles inboth groups, except Fas mRNA, which was not expressed in thepre-antral follicles. The expression of p53, Bcl2, Bax and FasLmRNA was similar in vitrified and non-vitrified groups; however,Fas mRNAs were more strongly expressed in the antral folliclesof the vitrified group than of the control group (P < 0.05).The expression of survivin 140 was lower in the antral folliclesof the vitrified group than of the control group (P < 0.05).FACS analysis showed that the percentage of intact cells waslower in the vitrified group than in the non-vitrified group(P < 0.05). This study demonstrated no signs of apoptosisultrastructurally in cultured follicles; however, vitrificationwas shown to affect the expression of some genes related toapoptosis.     

休克淋巴液对大鼠肺微血管内皮细胞凋亡相关基因表达的影响

目的：观察休克淋巴液对大鼠肺微血管内皮细胞（PMVECs）凋亡相关基因表达的影响，探讨休克淋巴液诱导PMVECs细胞凋亡的分子机制。方法：无菌条件下复制大鼠重症失血性休克模型，引流休克时肠系膜淋巴液或收集门静脉血，同时引流正常的淋巴液或正常门静脉血作为对照。以不同处理因素与第3代原代培养的PMVECs共同孵育，应用流式细胞仪检测细胞凋亡率，RT-PCR检测凋亡相关基因bcl-2、bax及fas、fas L的表达。结果：4%终浓度的休克淋巴液作用4 h后，PMVECs凋亡率为9.86%±3.24%，显著高于其它组（P<0.01）；4%终浓度的休克淋巴液作用6 h后，PMVEC的fas、fas L、bax mRNA表达高于其它组、bcl-2 mRNA表达低于其它组（P<0.01）。结论：休克淋巴液可诱导大鼠PMVECs凋亡，其机制与凋亡促进基因fas、fas L、bax表达增强、凋亡抑制基因〖STBX〗bcl-2〖STBZ〗表达降低有关。     

Effects of exercise intensity on lymphocyte apoptosis induced by oxidative stress in men

Exercise is linked with intensity-dependent immune response. Intracellular redox status is important in programmed cell death. This study, by closely examining 18 sedentary men who exercised moderately and severely (ie. 60% and 80% VO_2max, respectively) for 40 min, investigated how exercise intensities influence intracellular redox status and oxidative stress-induced apoptosis in lymphocyte. Intracellular superoxide and reduced glutathione (GSH) levels, lipid peroxidation, mitochondrial transmembrane potential (MTP), active caspases contents, phosphotidyl serine (PS) exposure, and DNA fragmentation in lymphocytes were determined. Moreover, sublethal oxidative stress was administered by treating the lymphocyte with H₂O₂, to closely approximate in vivo pro-oxidative conditions. Immediately or 24 h after severe exercise, (1) lymphocyte GSH level and MTP had diminished while active caspase-8, -9, and -3 contents and DNA fragmentation had risen; and (2) H₂O₂ induced- lymphocyte PS exposure and DNA fragmentation were enhanced. In contrast, lymphocyte MTP, caspases activation, PS exposure, and DNA fragmentation were unaltered immediately following moderate exercise, whereas GSH level rose, lipid peroxidation diminished, and H₂O₂ induced- PS exposure and cell damage reduced 24 h after this exercise. These results suggest that heavy exercise diminishes lymphocyte GSH content and subsequently enhances the oxidative stress-induced apoptosis. However, moderate exercise attenuates lymphocyte apoptosis induced by oxidative stress, possibly by improving intracellular anti-oxidative capacity.     

实验性心肌肥厚大鼠血浆与心肌儿茶酚胺含量变化及黄芪的影响

结扎大鼠腹主动脉形成实验性心肌肥厚，对动物血浆及左心室组织中肾上腺素、去甲肾上腺素含量与心肌肥厚程度，以及黄芪注射液和卡托普利抗肥厚作用之间的相关性进行研究。手术4周后开始连续给药8周。以动物的心脏重量衡量心肌肥厚程度，用HPLC法测定血浆及左心室组织中肾上腺素和去甲肾上腺素含量，以SPSS统计软件对二者的相关性进行分析。结果显示模型组动物肾上腺素在血浆和心室组织中的含量均比对照组升高，去甲肾上腺素的血浆浓度比对照组升高，而其左心室组织中含量则低于对照组。黄芪注射液和卡托普利有不同程度的抗心肌肥厚作用，并可部分纠正肾上腺素和去甲肾上腺素含量的异常变化。相关性分析结果显示，心肌肥厚程度（全心重量、左心室重量）与左心室组织中去甲肾上腺素含量呈显著负相关性（P＜0．01）。上述结果提示：药物改变体内儿茶酚胺类物质含量可在一定程度上反映药物对心肌肥厚程度的影响。     

Myocardin gene regulatory variants as surrogate markers of cardiac hypertrophy - study in a genetically homogeneous population

Myocardin is thought to contribute to heart hypertrophy as assessed in animal models. The aim of this study was to identify polymorphisms on the myocardin gene and investigate possible relationships with left ventricular structure in human hypertrophic cardiomyopathy (HCM). Eighty-four native Cretan individuals (36 patients with HCM and 48 healthy controls) were examined by direct sequencing and subsequent restriction fragment length polymorphism analysis and six polymorphisms were identified in the promoter region at positions −435T>C (rs758187), −629A>T (rs8071072), −1030C>G (rs1233851), −1069A>G, −1166A>G and −1406G>A (rs976906). Allele and haplotype frequencies were not significantly different between patients and controls. However, patients carrying the [−435C;−629T] allelic variant had decreased left ventricular wall thickness (LVWT, p = 0.020) and left ventricular mass (p = 0.006) as compared with the wild-type genotype. Carrier status of this myocardin promoter allelic variant was also associated with significant lower myocardin mRNA levels in peripheral blood (p = 0.039). Thus, a myocardin promoter allelic variant existing in the normal Cretan population was associated with decreased left ventricular mass in HCM patients and decreased myocardin mRNA levels in peripheral blood. Our results may be limited by the limited sample size, but are strengthened by the genetic homogeneity of the Cretan population. Our data suggest that functional natural myocardin promoter variation might be a genetic factor contributing to inter-individual differences in the development of cardiac hypertrophy.     

Homocysteine induces cardiac hypertrophy by up-regulating ATP7a expression

Aims: The aim of the study is to investigate the molecular mechanism by which homocysteine (Hcy) induces cardiac hypertrophy. Methods: Primary cardiomyocytes were obtained from baby Sprague-Dawley rats within 3 days after birth. Flow cytometry was used to measure cell sizes. Quantitative real-time polymerase chain reaction was performed to measure the expression of β-myosin heavy chain and atrial natriuretic peptide genes. Western blotting assay was employed to determine ATP7a protein expression. Cytochrome C oxidase (COX) activity test was used to evaluate the activity of COX. Atomic absorption spectroscopy was performed to determine copper content. siRNAs were used to target-silence the expression of ATP7a. Results: Hcy induced cardiac hypertrophy and increased the expression of cardiac hypertrophy-related genes. ATP7a was a key factor in cardiac hypertrophy induced by Hcy. Reduced ATP7a expression inhibited cardiac hypertrophy induced by Hcy. Elevated ATP7a expression induced by Hcy inhibited COX activity. Enhanced ATP7a expression inhibited COX activity by lowering intracellular copper content. Conclusions: Hcy elevates ATP7a protein expression, reduces copper content, and lowers COX activity, finally leading to cardiac hypertrophy.     

The assessment of cardiac hypertrophy at autopsy

The total weight of the normal adult human heart as well as that of each ventricle is proportional to body size. Body weight is superior to height as a predictor of total heart and isolated ventricular weights. Ventricular wall thickness is an insensitive means of assessing ventricular hypertrophy. Heart weight is a poor predictor of isolated right ventricular mass but a slightly better predictor of isolated left ventricular mass. The only method of determining the presence or absence of hypertrophy with confidence is to use the Fulton technique for isolated ventricular weights. The use of an arbitrary upper and lower limit, as currently used, for isolated ventricular weights obtained by Fulton's method may, however lead to errors in determining the presence or absence of ventricular hypertrophy.