低强度激光血管内照射对实验性糖尿病兔血液流变性质的影响

本实验用３８只实验性糖尿病兔,分别采用１．２ｍｗ、１．５ｍｗ、２．２ｍｗ×５０分钟三组不同剂量Ｈｅ—Ｎｅ激光,分两批作一次性血管内照射,测定其红细胞变形能力等８项血液流变学指标,并观察指标随时间的变化。结果表明：（１）激光照射后血液粘度降低,红细胞聚集性降低,且在２４小时内就有反映,５—７天仍然有效;（２）能提高红细胞变形能力,以照射后第３天最明显。５—７天后会回复照射前水平。此结果可为低强度激光血管内照射临床应用选择照射频度提供参考（３）可改善红细胞刚度,但时间上反映较迟     

美托洛尔舌下含服治疗老年急症高血压(24例临床报告)

本文旨在评估舌下含服美托洛尔对老年高血压急症的降压效果。方法：２４例老年急症高血压患者,于舌下含服美托洛尔５０ｍｇ前及含服后５、１０、３０、６０及１２０分钟,动态监测血压及心率,并比较用药前及用药后各时间段降压效果。结果：（１）治疗前、治疗后５、１０分钟,均有非常显著差异（Ｐ＜００１,Ｐ＜００５）,１０分钟血压降至安全水平,３０分钟完全降至正常,且降压效应持续至２小时。（２）无明显副作用。结论：舌下含服美托洛尔对老年急症高血压患者,是一种速效,稳效,无明显副作用,且方法简便的急症降压方法。     

咖啡因加热休克诱导皱纹盘鲍多倍体的研究

报道了用咖啡因加热休克抑制受精卵的第一极体的释放诱导皱纹盘鲍（Ｈａｌｉｏｔｉｓ ｄｉｓｃｕｓ ｈａｎｎａｉ Ｉｎｏ）多倍体的研究结果。皱纹盘鲍的卵在２１℃海水中受精,受精后１０分钟开始处理,药物浓度分别为２．５ｍｍｏｌ／Ｌ、５ｍｍｏｌ／Ｌ、１０ｍｍｏｌ／Ｌ,热休克温度分别为２４℃、２６℃、２８℃,处理的持续时间为１０分钟至３０分钟,共分５个时间段。结果表明,药物浓度５ｍｍｏｌ／Ｌ和１０ｍｍｏｌ／Ｌ     

紫外光对新生小鼠表皮郎格汉斯细胞影响的组织化学和超微组织化学研究

用ＡＴＰ酶组化、超微组化和图像分析法观察紫外光对新生小鼠表皮郎格汉斯细胞（ＬａｎｇｅｒｈａｎｓＣｅｌｌ,Ｌ．Ｃ）的影响。新生小鼠背皮暴露于紫外光后的不同时间,对Ｌ．Ｃ的密度、形态和灰度以及超微结构进行观察。结果显示：经紫外光照射５分钟后,Ｌ．Ｃ的ＡＴＰ酶活性开始受到抑制,细胞密度减少。各实验组与对照组相比,Ｐ＜０．０１。而５分钟组至９０分钟组组间无显著差异。各实验组光、电镜观察均显示细胞形态呈退行性变化。     

马桑内酯对培养的大鼠大脑皮层神经元γ─氨基丁酸、生长抑素分泌的影响

本文利用培养的大鼠大脑皮层神经元,在不同浓度马桑内酯（５μｍｏｌ／Ｌ～２５０μｍｏｌ／Ｌ）作用后１２、２４、４８小时,应用双抗夹心法检测各时间点培养上清中γ－氨基丁酸和生长抑素含量。结果表明,各浓度中以２５μｍｏｌ／Ｌ马桑内酯作用最明显,在此浓度作用后１２小时,γ－氨基丁酸分泌受抑（抑制率为８．３％）,生长抑素分泌则增加（增加率为２０．４％）。作用后２４、４８小时,γ－氨基丁酸分泌进一步受抑（抑制率为１０．６％、１４．５％）,而生长抑素分泌则呈现增加幅度降低趋势（增加率为１１．７％、８．２％）。与未加药组相比,γ－氨基丁酸在三个时间点均有统计学意义（Ｐ＜０．０５）,而生长抑素只在加药后１２小时有统计学意义（Ｐ＜０．０５）、本文对马桑内酯作用后两种神经递质变化的意义进行了讨论。     

戊乙奎醚与咪唑安定作为妇科腹腔镜手术麻醉前用药对患者血流动力学的影响

目的:戊乙奎醚与咪唑安定作为妇科腹腔镜手术麻醉前用药对患者血流动力学的影响.方法:将150例美国麻醉师协会(ASA)分级Ⅰ～Ⅱ级妇科腹腔镜手术患者(病种包括子宫肌瘤、宫外孕、单纯卵巢囊肿)随机分为2组,每组75例.于麻醉诱导前10分钟分别静注戊乙奎醚0.01 mg/kg (A组)、咪唑安定0.01 mg/kg (B组).记录并比较注药后5分钟,10分钟,20分钟患者口干程度的视觉模拟评分(visual analogue scale,VAS);记录并比较患者注药前10分钟(P1)、注药后10分钟(P2)、患者意识消失时(P3)、手术开始时(P4)、手术开始后1小时(P5)、手术结束时(P6)、苏醒后1小时(P7)时的脉搏血氧饱和度(SpO2)、心率(HR)、收缩压(SBP)、舒张压(DBP);记录并比较术后气管及口腔内分泌物量、动脉血乳酸(ABL)含量.结果:对两组患者于麻醉诱导前分别注射0.01 mg/kg戊乙奎醚和0.01 mg/kg咪唑安定,结果显示B组患者在给药后5分钟,10分钟,20分钟心率较A组相同时间点心率有显著升高(P＜0.05),口干程度VAS评分B组显著高于A组.手术期间两组血液动力学变化为B组注药后血压、心率均较基础值显著降低(P＜0.05);两组患者注药前后脉搏氧饱和度均无显著变化(P＞0.05).B组气管及口鼻腔分泌物的量明显多于A组,且术后测定动脉血乳酸含量B组显著高于A组(P＜0.05).结论:于麻醉诱导前20分钟静注戊乙奎醚0.01 mg/kg可以有效减少患者术中及术后口腔、呼吸道分泌物,而不致心率增加和血压升高,对患者血流动力学无显著影响;对患者微循环有明显改善作用.     

磷酸化底物肽的硫代磷酸化及荧光标记

以蛋白激酶Ａ的一磷酸化底物肽ＬＲＲＡＳＬＧ为模型肽,研究了硫代磷酸化及荧光标记反应条件。荧光标记试剂５－｛「（（２－碘代乙酰）氨）乙基」氨基｝萘－１－磺酸（１,５－ＩＡＥＤＡＮＳ）适宜浓度为１．６ｍｍｏｌ／Ｌ,标记反应缓冲液的适宜ｐＨ为７至８。实验了标记肽分别在Ｎ－端序列分析、电喷雾质谱和０．１％三氟乙酸存在下的稳定性。比较了标记肽和标记肽的紫外吸收光谱的差异特征。初步显示高效液相色谱蛋白酶解肽谱     

循环血容量对人血浆心房利钠多肽有影响

心房利钠多肽(ANP),有强大的利钠和利尿作用,对调节体液平衡有重要作用。1984年由Kangawa等确定其结构,并开始用RIA 法测定其浓度。作者用生理盐水持续静脉滴注或注射速尿后步行试验,使循环血容量增加或减少,以观察血浆ANP 的浓度。试验以8例19～20岁的健康男性为观察对象。盐水负荷试验为晨起空腹,2小时内静滴生理盐水1000 ml,静滴前及静滴后30、60及120分钟分别测定血浆ANP     

异丙肾上腺素对心内神经节中肽能递质VIP影响

异丙肾上腺素是临床常用的心脏骤停的抢救药物。为了研究该药对心内神经节中肽能递质的影响,本文在大鼠皮下注射异丙肾上腺素５ｍｇ／ｋｇ,连续三天,后固定取心房后壁,用免疫组化结合图像分析,观察心内神经节中肽能递质ＶＩＰ的变化。对照组大鼠心内神经节中含有ＶＩＰ免疫反应（ＶＩＰ－ＩＲ）阳性神经纤维和胞体;实验组大鼠心内神经节中含有ＶＩＰ－ＩＲ阳性神经纤维和胞体呈不同程度增多。其中ＶＩＰ－ＩＲ阳性神经纤维积分光密度较对照组增加２５．３％,而神经胞体积分光密度只增加８．１％。结果提示：１．大鼠心内神经节中ＶＩＰ－ＩＲ阳性神经纤维可能有两个来源：即心内ＶＩＰ－ＩＲ阳性神经节细胞和心外副交感神经元;２．异丙肾上腺素对心脏的作用并非单一的直接作用,其中部分是通过影响心内神经节中肽能递质的变化而发挥间接作用。     

造林整地对栗钙土钙积层化学性质干扰的研究

采用对比分析方法,对不同年龄杨树人工林地整地与未整地土壤化学性质进行了研究．结果表明,经犁沟整地破除钙积层后,土壤化学性质约在１０７年恢复到整地前状态,随后土壤养分迅速减小,以至低于整地前水平．２０年后随着林地有机物质的积累,养分开始回升,最终林地养分高于整地前水平．土壤养分恢复的先后顺序为有机质、ＣａＣＯ３、有效Ｎ、全Ｐ、全Ｎ、速效Ｋ和有效Ｐ,恢复周期分别为６、７、７５、９、１０、１７、１７５年．钙积层部位恢复周期为１１４年,恢复先后顺序为有效Ｎ、全Ｐ、有机质、速效Ｋ、ＣａＣＯ３、全Ｎ和有效Ｐ,恢复周期为５５、６、６、８５、９５、１０、３４年．     

Influence of aminergic and peptidergic substances on heart beat frequency in the stick insect Carausius morosus (Insecta,Phasmatodea)

The dorsal heart of the Indian stick insect, Carausius morosus, is responsible for the anterograde flow of hemolymph to the aorta and into the body cavity. The contraction frequency of the insect heart is known to be influenced by several substances of neural source. Here, a semi‐exposed heart assay was employed to study the effect of an aminergic substance (octopamine) and three neuropeptides (C. morosus hypertrehalosemic hormone [Carmo‐HrTH], crustacean cardioactive peptide [CCAP], and proctolin) on heart contraction. The contraction frequency was measured as beats per minute in adults ligated between the head and the prothorax. All three investigated neuropeptides had a stimulatory effect on heart contraction that lasted approximately 6 min, after which the normal heart beat rate was restored. Proctolin and CCAP stimulated the rate of heart beat also in unligated stick insects, whereas Carmo‐HrTH was active only in ligated insects. The latter could suggest that when the stick insect is not ligated, a competing substance may be released from the head of C. morosus; the competing substance is, apparently, not physiologically active but it binds or blocks access to the receptor of Carmo‐HrTH‐II, thereby rendering the HrTH peptide “not active.” In ligated stick insects, 6.7 × 10^?8 M Carmo‐HrTH‐II significantly increased the heart beat rate; higher doses resulted in no further increase, suggesting the saturation of the HrTH receptor. Octopamine inhibited the rate at which the heart contracted in a dose‐dependent manner; inhibition was achieved with 10^?4 M of octopamine.     

Chytrid infection reduces thoracic beat and heart rate of <Emphasis Type="Italic">Daphnia</Emphasis><Emphasis Type="Italic">pulicaria</Emphasis>

Zooplankters are hosts to numerous endo- and ectoparasites, some of which have dramatic impacts on their hosts. Epizootics on zooplankton are probably more widespread in lake systems than it is currently known, and few studies have explored the direct and indirect importance of parasitism in aquatic food webs. In addition, our understanding of the sublethal effects of parasitic infections on host organisms and populations is limited. We used a novel electro-chemical based technique to measure in the outflow of the feeding current changes in the beat rate of the thoracic appendages in female Daphnia pulicaria. We observed simultaneously the heart rates and compared chytrid infected animals with uninfected gravid and non-gravid ones. We found in uninfected animals a thoracic beat rate of 3.81 ± 018 Hz and a heart rate of 4.67 ± 0.42 Hz. Gravid daphnids had a 14% lower thoracic beat rate (3.27 ± 0.30 Hz) than non-gravid females while the heart rate did not significantly differ (4.48 ± 0.28 Hz). In contrast, infected animals showed a 22% lower thoracic beat rate (2.96 ± 0.47 Hz) and a 36% lower heart rate (2.98 ± 0.5 Hz) when compared with uninfected non-gravid females. We discuss the ways Daphnia are affected by Polycaryum leave infections on the individual and population level.     

A comparative study of the adrenergic innervation of the teleost heart

Summary An adrenergic cardiac innervation has been found in the following teleost species:Platycephalus bassensis (Platycephalidae);Atopomycterus nicthemerus (Diodontidae);Aracana ornata (Ostraciontidae);Torquiginer glaber (Tetraodontidae);Aldrichetta forsteri (Mugilidae);Anguilla australis occidentalis (Anguillidae). In contrast, no evidence for an adrenergic cardiac innervation was found in the pleuronectid,Rhombosolea tapirina.Fluorescence histochemical studies indicated that adrenergic nerves in the sinus venosus and atrium entered via the vagus, whereas those to the ventricle passed mainly along the coronary vasculature. No fluorescent nerves were observed in the heart ofRhombosolea.Transmural stimulation of these adrenergic nerves increased the force of beat in the atrium and ventricle ofPlatycephalus, Atopomycterus andAracana, and in the atrium only ofTorquiginer, Aldrichetta andAnguilla. In addition stimulation of the abdominal vagus nerve in the presence of hyoscine increased the force of beat and heart rate in spontaneously beating sinus-atrium preparations of all species exceptRhombosolea. Applied catecholamines increased the force of beat and heart rate in the spontaneously beating heart of all species includingRhombosolea.     

Electrophysiological investigation of the antennal heart of Periplaneta americana and its reactions to proctolin

Some physiological parameters of the antennal heart, an accessory circulatory organ in the head of Periplaneta americana and the effect of the neuropeptide proctolin on it were investigated. The beat frequency of the antennal heart in vivo or semiisolated is about 2–3 times slower than that of the dorsal vessel and not coordinated with the latter. The extracellular ECG of the antennal heart has a simple biphasic shape with a total duration of 588.7 ± 38.2 ms. Intracellularly recorded parameters showed characteristics typical of myogenic rhythmicity: a slow depolarization with a rate of rise of 7.5 ± 0.7 mV/s, followed by an action potential of 54.9 ± 1.2 mV with a relatively long duration of 201.6 ± 10.8 ms, absence of overshoots and resistance to TTX. Proctolin produced a marked enhancement of the frequency of beat of the antennal heart up to about 400% with a high sensitivity (threshold concentrations: 5·10^?9M). The dose-response curve shows a linear relationship between the logarithm of the concentration and the percentage increase in beat frequency. The electrical event most influenced by proctolin was the slow pacemaker depolarization, whose rate of rise was enhanced up to 240%. The action potential remained unchanged; the depolarization of the resting potential was very small and the input resistance did not change. The antennal heart responds to neurohormone D, another neuropeptide in insects, in a similar way as it does to proctolin. The mode of action of proctolin on the antennal heart is discussed in comparison to that found in other systems.     

Stimulation by volume expansion of atrial natriuretic peptide release from perfused rat heart

The release of immunoreactive (ir-) rat atrial natriuretic peptide (rANP) with volume expansion in in situ retrograde perfused rat heart was examined. The volume expansion induced by the infusion of the perfusion medium into the right atrium increased the mean right atrial pressure and the ir-rANP release without changing the rate of the heart beat. There was a significant correlation between the peak values of ir-rANP release and those of mean atrial pressure. The bilateral cervical vagotomy did not effect the ir-rANP release induced by the volume expansion. Therefore, it is highly likely that the stimulatory effect of volume expansion on rANP release is due to, at least in part, the atrial distension accompanied by an increase in mean atrial pressure, not involving a vagal system.     

Effects of streptozotocin-induced diabetes on action potentials in the sinoatrial node compared with other regions of the rat heart

In vivo biotelemetry studies have demonstrated that heart rate (HR) is progressively and rapidly reduced after administration of streptozotocin (STZ) and that the reduction in HR can be partially normalized with insulin replacement. Reductions in HR have also been reported in isolated perfused heart and superfused right atrial preparations suggesting that intrinsic defects in the heart are at least partly responsible for the bradycardia. The regional effects of STZ-induced diabetes mellitus (DM) on action potentials (APs) in the sinoatrial node (SAN), right and left atria and ventricles have been compared in the spontaneously beating Langendorff perfused rat heart 10–12 weeks after treatment. HR was significantly reduced in STZ-induced diabetic rat heart (174 ± 9 BPM) compared to controls (241 ± 12 BPM). The duration of AP repolarization at 50% and 70% from peak AP was significantly prolonged in SAN, right atrium and right ventricle from STZ-induced diabetic rat compared to age-matched controls. In the SAN AP duration (APD) at 50% and 70% were 51.7 ± 2.2 and 59.5 ± 2.3 ms in diabetic rat heart compared to 45.2 ± 1.7 and 50.0 ± 1.6 ms in controls, respectively. In contrast APD at 50% and 70% were not significantly altered in the left atrium and left ventricle. Regional defects in the expression and/or electrophysiology of SAN ion channels, and in particular those involved in AP repolarization, might underlie heart rhythm disturbances in the STZ-induced DM rat.     

Neuropeptides regulate the cardiac activity of a prosobranch mollusc,Rapana thomasiana

Summary Involvement of neuropeptides in the regulation of cardiac activity in a prosobranch mollusc, Rapana thomasiana, was studied physiologically as well as immunohistochemically. A catch-relaxing peptide (CARP) showed strong inhibitory effects on the heart with a lower threshold than acetylcholine. The action of CARP was in contrast to that of another neuropeptide, FMRFamide, which has previously been shown to enhance the heart beat. Benzoquinonium blocked the effects of acetylcholine and stimulation of right cardiac nerves 1 and 3b, but not those of CARP, suggesting that the effects of nerve stimulation are mainly due to the release of acetylcholine. Immunohistochemical examinations demonstrated that FMRFamide-like and CARP-like immunoreactive neurons are distributed in the visceral ganglia. Although a neuron appeared to show weak immunoreactivity to both antisera, evidence for the coexistence of peptides in a single neuron was not exhibited. Positive immunoreactivity to FMRFamide and CARP antisera also appeared in right cardiac nerves 1 and 3. In the heart, FMRFamide- and CARP-like immunoreactive fibers were restricted to the atrium and the aortic end of the ventricle, consistent with the morphological observation of innervation. The present results suggest that FMRFamide- and CARP-like peptides are involved in regulating the heart beat.     

A sandwich enzyme linked immuno-sorbent assay for the determination of rat heart fatty acid-binding protein using the streptavidin-biotin system. Application to tissue and effluent samples from normoxic rat heart perfusion

An enzyme linked immuno-sorbent assay (ELISA) of the sandwich type for the determination of heart-type fatty acid-binding protein (H-FABPc) was developed, making use of the streptavidin-biotin system. The assay turned out to be virtually disturbance insensitive and showed a detection limit for H-FABPc of 0.2 micrograms/l with an intra- and inter-assay variation of 5% and 14%, respectively. The H-FABPc content of adult rat heart muscle was found to be 0.740 +/- 0.120 mg/g wet weight. The H-FABPc content of a number of skeletal muscles varied from 0.013 to 0.303 mg/g wet weight and was related to the content of type I muscle fibers of these tissues, suggesting a role for H-FABPc in intracellular fatty acid metabolism. The assay was further applied to study the release of H-FABPc from isolated rat heart during normoxic Langendorff perfusion, as compared to that of lactate dehydrogenase (LDH), into fluid derived from the right ventricular cavity (Qrv) and that from the interstitial space (Qi). Total release of H-FABPc per 15 min amounted to 0.015 +/- 0.010% but that of LDH to 0.080 +/- 0.040% of their total tissue content. Furthermore, for both H-FABPc and LDH 80% was released into Qi, which only accounted for 1-2% of total flow. These findings suggest that during normoxic perfusion of rat heart H-FABPc, and LDH are released from different cellular compartments and that the bulk amount of released intracellular proteins is transported via the lymph instead of being directly released into the bloodstream.     

Rat corin gene: molecular cloning and reduced expression in experimental heart failure

Stored cardiac pro-atrial natriuretic peptide (pro-ANP) is converted to ANP and released upon stretch from the atria into the circulation. Corin is a serin protease with pro-ANP-converting properties and may be the rate-limiting enzyme in ANP release. This study was aimed to clone and sequence corin in the rat and to analyze corin mRNA expression in heart failure when ANP release upon stretch is blunted. Full-length cDNA of rat corin was obtained from atrial RNA by RT-PCR and sequenced. Tissue distribution as well as regulation of corin mRNA expression in the atria were determined by RT-PCR and RNase protection assay. Heart failure was induced by an infrarenal aortocaval shunt. Stretch was applied to the left atrium in a working heart modus, and ANP was measured in the perfusates. The sequence of rat corin cDNA was found to be 93.6% homologous to mouse corin cDNA. Corin mRNA was expressed almost exclusively in the heart with highest concentrations in both atria. The aortocaval shunt led to cardiac hypertrophy and heart failure. Stretch-induced ANP release was blunted in shunt animals (control 1,195 +/- 197 fmol.min(-1).g(-1); shunt: 639 +/- 99 fmol.min(-1).g(-1), P < 0.05). Corin mRNA expression was decreased in both atria in shunt animals [right atrium: control 0.638 +/- 0.004 arbitrary units (AU), shunt 0.566 +/- 0.014 AU, P < 0.001; left atrium: control 0.564 +/- 0.009 AU, shunt 0.464 +/- 0.009 AU, P < 0.001]. Downregulation of atrial corin mRNA expression may be a novel mechanism for the blunted ANP release in heart failure.     

Human cardiac plasma concentrations of atrial natriuretic peptide quantified by radioreceptor assay

The presence of high affinity receptors for atrial natriuretic peptide in bovine adrenal cortex has enabled the development of a sensitive, specific and rapid radioreceptor assay for this peptide in human plasma. In 18 normal subjects, venous plasma atrial natriuretic peptide concentration ranged from 6 to 65 pM. This plasma concentration was two-fold higher in right atrium as compared to venous blood in 12 patients investigated by cardiac catheterisation, confirming that the right atrium is the site of release of atrial natriuretic peptide into circulation. There was a further step up in plasma atrial natriuretic peptide concentration between pulmonary arterial and aortic plasma. This finding indicates that released hormone in man may undergo further activation in the lungs, or that there may be direct release from the left atrium.