Archives internationales de physiologie, de biochimie et de biophysique最新文献_第10页

Diminished myofibrillar sensitivity to calcium produced by simultaneous superfusion of cAMP and phosphodiesterases inhibitors in toad (Bufo arenarum Hensel) ventricle. cAMP和磷酸二酯酶抑制剂同时灌注在蟾蜍(Bufo arenarum Hensel)心室中降低肌纤维对钙的敏感性。

Archives internationales de physiologie, de biochimie et de biophysique Pub Date : 1993-09-01 DOI: 10.3109/13813459309003925

M V Petroff, A Mattiazzi

{"title":"Diminished myofibrillar sensitivity to calcium produced by simultaneous superfusion of cAMP and phosphodiesterases inhibitors in toad (Bufo arenarum Hensel) ventricle.","authors":"M V Petroff, A Mattiazzi","doi":"10.3109/13813459309003925","DOIUrl":"https://doi.org/10.3109/13813459309003925","url":null,"abstract":"Experiments were performed in EGTA-skinned trabeculae from toad ventricle to explore the effects of the cAMP on calcium sensitivity of the contractile system. 10(-3) M of the cAMP derivative dibutyryl cAMP (dcAMP) failed to affect calcium sensitivity of chemically skinned ventricular trabeculae. 10(-5) M of the phosphodiesterase inhibitor isobutylmethylxantine (IBMX) produced a significant shift to the left of the tension-pCa relationship. The computed half maximally activating pCa (pCa50) were 6.32 +/- 0.03 and 6.40 +/- 0.01 in the absence and presence of IBMX respectively, (P < 0.05). Simultaneous perfusion of 10(-5) M IBMX and 10(-3) M dcAMP suppressed the leftward shift of the tension-pCa curve induced by IBMX (pCa50: 6.33 +/- 0.04 and 6.33 +/- 0.05 for control and IBMX respectively). Perfusion with the phosphodiesterase inhibitor milrinone (10(-5) M), did not produce any significant changes in the tension-pCa relationship. Simultaneous perfusion of 10(-5) M milrinone and 10(-3) M dcAMP significantly shifted to the right the tension-pCa curve. The computed pCa50 were 6.32 +/- 0.02 and 6.23 +/- 0.03 under control conditions and in the presence of dcAMP plus milrinone respectively (P < 0.05). In agreement with what has been described in mammalian heart, the results indicate that in amphibian ventricle, cAMP produced a decrease in the calcium sensitivity of the contractile proteins that is only evident in the presence of phosphodiesterase inhibitors. It is suggested that this decrease in myofilament sensitivity to calcium may be one of the mechanisms by which beta-agonists enhance myocardial relaxation in the amphibian heart.","PeriodicalId":77008,"journal":{"name":"Archives internationales de physiologie, de biochimie et de biophysique","volume":"101 5","pages":"279-83"},"PeriodicalIF":0.0,"publicationDate":"1993-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/13813459309003925","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18516180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Diurnal rhythm of the in vivo acetate metabolism to CO2 and nonsaponifiable lipids by neonatal chick. 雏鸡体内醋酸盐对CO2和非皂化脂代谢的昼夜节律。

Archives internationales de physiologie, de biochimie et de biophysique Pub Date : 1993-09-01 DOI: 10.3109/13813459309003926

V Arce, J A Aguilera, A Linares, E Garcia-Peregrin

{"title":"Diurnal rhythm of the in vivo acetate metabolism to CO2 and nonsaponifiable lipids by neonatal chick.","authors":"V Arce, J A Aguilera, A Linares, E Garcia-Peregrin","doi":"10.3109/13813459309003926","DOIUrl":"https://doi.org/10.3109/13813459309003926","url":null,"abstract":"The in vivo incorporation of acetate into nonsaponifiable lipids was studied in different tissues from 14-day-old chick. Total nonsaponifiable lipids (nmol/30 min/g tissue) were mainly synthesized in testicles and liver. The in vivo CO2 production from acetate by 1-day-old chick did not exhibit diurnal variations. However, in 14-day-old chick, a maximal value was observed in the middle of the light period, while a minimal value was found 9 h after the start of the dark period. No significant diurnal differences were detected in the in vivo acetate incorporation into nonsaponifiable lipids by liver and duodenal mucosa from 1-day-old chick. Nevertheless, a clear diurnal rhythm was found in liver and duodenal mucosa from 14-day-old chick, but not in brain and kidney from animals of the same age. Distribution of radioactivity from (1-14C)acetate among the different constituents of the nonsaponifiable fraction has been also studied at 3-h intervals. Cholesterol was the major sterol formed from acetate by chick liver at any time of day. In duodenal mucosa and kidney, maximal values in the percentage of cholesterol synthesized were observed during the light period.","PeriodicalId":77008,"journal":{"name":"Archives internationales de physiologie, de biochimie et de biophysique","volume":"101 5","pages":"285-8"},"PeriodicalIF":0.0,"publicationDate":"1993-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/13813459309003926","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18516179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Human neonatal red blood cells. An experimental model for the study of calcium-activated potassium channel refractoriness. 人类新生儿红细胞。钙活化钾通道耐火度研究的实验模型。

Archives internationales de physiologie, de biochimie et de biophysique Pub Date : 1993-09-01 DOI: 10.3109/13813459309003928

R E Serrani, I A Gioia, J L Corchs

引用次数: 0

Variations in lactate apparent clearance during rest and exercise in normal man. 正常人休息和运动时乳酸表观清除率的变化。

Archives internationales de physiologie, de biochimie et de biophysique Pub Date : 1993-09-01 DOI: 10.3109/13813459309003929

M A Francaux, P A Jacqmin, X G Sturbois

{"title":"Variations in lactate apparent clearance during rest and exercise in normal man.","authors":"M A Francaux, P A Jacqmin, X G Sturbois","doi":"10.3109/13813459309003929","DOIUrl":"https://doi.org/10.3109/13813459309003929","url":null,"abstract":"The purpose of this study is to present a simple kinetic model for the study of the lactate metabolism. This model based on pharmacokinetic theory, does not require labelled molecules and yields a finer approach to lactate metabolism than does a simple observation of blood lactate concentration. The variations in parameter values have been studied in six male subjects after intensive exercise (385 W, 110 rpm and 1 min) (IE) followed by three different recovery periods: passive recovery (RE), moderate exercise (ME) and heavy exercise (HE). Blood lactate concentration was measured prior to IE and during the first hour of recovery. After mathematical treatment, the results show that the apparent clearance increases 2.83 +/- 0.76 fold from RE to ME and 1.96 +/- 0.61 fold from RE to HE. The steady state blood lactate concentration induced by the intensity of recovery (La(ss)) increases slightly (1.53 +/- 0.37 fold) from RE (1.40 +/- 0.36 mmol.l-1) to ME (2.04 +/- 0.32 mmol.l-1). Then La(ss) increases markedly (3.78 +/- 0.91 mmol.l-1) during HE (2.81 +/- 0.78 fold the La(ss) value at RE). The ratio between the apparent rates of lactate production (F\"K0) during RE, ME and HE was calculated. F\"K0 increases in a linear way versus intensity of exercise recovery. It was concluded that in the human: 1) the blood lactate concentration is not an accurate indicator of lactate production, 2) in our experiment, the apparent lactate production is a linear function of exercise intensity and 3) the abruptly increasing blood lactate concentration at a high level of exercise intensity is due to a decrease in apparent clearance.","PeriodicalId":77008,"journal":{"name":"Archives internationales de physiologie, de biochimie et de biophysique","volume":"101 5","pages":"303-9"},"PeriodicalIF":0.0,"publicationDate":"1993-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/13813459309003929","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18516679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Adrenal response to acute stress in mammillary medial nuclei lesioned rats. 乳腺内核损伤大鼠肾上腺对急性应激的反应。

Archives internationales de physiologie, de biochimie et de biophysique Pub Date : 1993-09-01 DOI: 10.3109/13813459309003924

M Suarez, N I Perassi

引用次数: 4

Melanin quantitation from human erythrocytes; interference by haeme derivatives. 人红细胞黑色素定量测定;血红素衍生物的干扰。

Archives internationales de physiologie, de biochimie et de biophysique Pub Date : 1993-09-01 DOI: 10.3109/13813459309003927

Z L Hegedus, U Nayak

{"title":"Melanin quantitation from human erythrocytes; interference by haeme derivatives.","authors":"Z L Hegedus, U Nayak","doi":"10.3109/13813459309003927","DOIUrl":"https://doi.org/10.3109/13813459309003927","url":null,"abstract":"Precipitates were obtained by 6 N HCl hydrolysis of human erythrocytes and subsequent extractions with ethanol-ether 1:1 and with tetrahydrofuran. The mean quantity of these precipitates (n = 16) was 16.60 +/- 1.60 (standard deviation) mg/ml, (15.09 +/- 1.45 mg/g) and from saline washed erythrocyte samples (n = 8) 16.65 +/- 0.73 mg/ml, (15.14 +/- 0.67 mg/g). A large part of these precipitates (about 74%) is associated with haemoglobin (in average 12.34 mg/ml). Melanins account for the difference (16.60-12.34) = 4.26 mg/ml, approximately 8.7% of haemoglobin-free erythrocyte solids. Precipitates from red cells, and from haemoglobin produced similar UV-VIS and IR spectra. The precipitates from haemoglobin are mainly derivatives of haeme (about 97%); the remaining approximately 3% are melanins from globin. The total melanins are about 1.3% of haeme-free solids of erythrocytes. Precipitation from the erythrocytes with 6 N HCl was also achieved in practically complete argon atmosphere, and similar quantities were obtained as those in air with the same UV-VIS and IR spectra. Since granules or solid particles are not found in the cytoplasm of normal human erythrocytes, we conclude that soluble melanins are present. Small amounts of melanins can be present in the membranes as well, since the precursors of melanins: norepinephrine, epinephrine are present in these membranes.","PeriodicalId":77008,"journal":{"name":"Archives internationales de physiologie, de biochimie et de biophysique","volume":"101 5","pages":"289-95"},"PeriodicalIF":0.0,"publicationDate":"1993-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/13813459309003927","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18516181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Changes induced by hypothyroidism in insulin secretion and in the properties of islet plasma membranes. 甲状腺功能减退引起的胰岛素分泌和胰岛质膜性质的改变。

Archives internationales de physiologie, de biochimie et de biophysique Pub Date : 1993-09-01 DOI: 10.3109/13813459309003922

G B Diaz, A A Paladini, M E Garcia, J J Gagliardino

{"title":"Changes induced by hypothyroidism in insulin secretion and in the properties of islet plasma membranes.","authors":"G B Diaz, A A Paladini, M E Garcia, J J Gagliardino","doi":"10.3109/13813459309003922","DOIUrl":"https://doi.org/10.3109/13813459309003922","url":null,"abstract":"This work was aimed at elucidating the effect of thyroid function on the physiology and biochemistry of the islet-cell population within the endocrine pancreas. To this end, we performed a comparative study of the physiochemical properties of islet-cell membranes and of the dynamics of glucose-induced insulin secretion in isolated pancreatic islets prepared from euthyroid i.e. control (C), hypothyroid (H), and thyroxin-supplemented hypothyroid (HT) rats. H rats were obtained by injecting normal rats with 131iodine, while HT rats consisted of H rats treated with thyroxin (T4). Insulin secretion was studied in isolated islets perifused with 3.3 and 16.6 mM glucose. Physicochemical properties of the partially purified islet plasma membranes were assessed by measurements of fluorescence polarization with the fluorophore 1,6-diphenyl-1,3,5-hexatriene (DPH) as a lipidic molecular probe. Insulin output during either the first or second phase of insulin secretion in H islets was significantly lower than in C islets. The slope of the curve in the second phase of insulin secretion was also lesser in H than in C islets, suggesting an additional defect in their velocity of hormone release. T4 administration of H rats reversed the decrease in insulin output to the range found in C islets but was incapable of correcting the defect in the hormone-secretion velocity. Several changes were found in the physicochemical properties of the membranes obtained from H islets as compared to C islets.(ABSTRACT TRUNCATED AT 250 WORDS)","PeriodicalId":77008,"journal":{"name":"Archives internationales de physiologie, de biochimie et de biophysique","volume":"101 5","pages":"263-9"},"PeriodicalIF":0.0,"publicationDate":"1993-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/13813459309003922","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18516176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 21

Effects of folic acid and methotrexate on arginase activity in regenerating rat liver tissue. 叶酸和甲氨蝶呤对再生大鼠肝组织精氨酸酶活性的影响。

Archives internationales de physiologie, de biochimie et de biophysique Pub Date : 1993-09-01 DOI: 10.3109/13813459309003923

J Nikolić, G Bjelaković, G Kocić

引用次数: 3

XVIth Congress of the Society of Biomechanics. Lille, France, 8-9 November 1991. Proceedings. 第十六届生物力学学会大会。1991年11月8日至9日，法国里尔。程序。

Archives internationales de physiologie, de biochimie et de biophysique Pub Date : 1993-09-01

引用次数: 0

Neonatal red blood cell lysis induced by hypertonic low ionic strength media. 高渗低离子强度介质诱导新生儿红细胞溶解。

Archives internationales de physiologie, de biochimie et de biophysique Pub Date : 1993-09-01 DOI: 10.3109/13813459309003919

J L Corchs, M J Corchs, R E Serrani

引用次数: 1