Membrane biochemistry最新文献

Effect of free radical scavengers on changes in ion conductance during exposure to therapeutic ultrasound. 自由基清除剂对暴露于治疗性超声时离子电导变化的影响。

Membrane biochemistry Pub Date : 1993-10-01 DOI: 10.3109/09687689309150271

M A Adinno, A M al-Karmi, D A Stoltz, J C Matthews, L A Crum

{"title":"Effect of free radical scavengers on changes in ion conductance during exposure to therapeutic ultrasound.","authors":"M A Adinno, A M al-Karmi, D A Stoltz, J C Matthews, L A Crum","doi":"10.3109/09687689309150271","DOIUrl":"https://doi.org/10.3109/09687689309150271","url":null,"abstract":"Ultrasound has been used in physical therapy for > 4 decades. Recent studies indicate that non-thermal mechanisms such as cavitation are involved in the observed effects. Free radicals and other highly reactive compounds are known to form during sonochemical reactions associated with acoustic cavitation. Using frog skin as a biological model, the possibility that the increase in ionic conductance (Gt) upon exposure to therapeutic ultrasound is due to the effect of free radicals generated by sonochemical reactions, was investigated. It was found that the presence of cystamine, cysteamine and sodium ascorbate significantly reduced the increase in conductance caused by the exposure to 300 mW/cm2 (1 MHz CW) therapeutic ultrasound. The attenuation in the effects was dependent on the concentration of the radical scavengers/antioxidants used, the incubation time, and the intensity of ultrasound. The effects were also dependent on the lipid solubility of free radical scavengers/antioxidants. The time constant for the recovery process of Gt in the presence of free radical scavengers and antioxidants after exposure to ultrasound was found to be not significantly different from control. These results suggest that the increase in Gt due to ultrasound is induced by free radicals and other reactive species generated from acoustic cavitation. This study provides an indirect evidence to the contingent that free radicals are generated and act inside the cells. Furthermore, the radical scavengers and antioxidants used provide protection from oxidative damage without being involved in the recovery of Gt towards steady state values after sonication.","PeriodicalId":18448,"journal":{"name":"Membrane biochemistry","volume":"10 4","pages":"237-47"},"PeriodicalIF":0.0,"publicationDate":"1993-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/09687689309150271","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19002787","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: 19

Properties of the ryanodine receptor present in the sarcoplasmic reticulum from lobster skeletal muscle. 龙虾骨骼肌肌浆网中ryanodine受体的特性。

Membrane biochemistry Pub Date : 1993-10-01 DOI: 10.3109/09687689309150270

E Olivares, N Arispe, E Rojas

{"title":"Properties of the ryanodine receptor present in the sarcoplasmic reticulum from lobster skeletal muscle.","authors":"E Olivares, N Arispe, E Rojas","doi":"10.3109/09687689309150270","DOIUrl":"https://doi.org/10.3109/09687689309150270","url":null,"abstract":"Microsomal sarcoplasmic reticulum (SR) fractions from lobster skeletal muscle were found to bind [3H]-ryanodine. [3H]-ryanodine binding was enhanced by AMP, Ca2+ and caffeine, and significantly diminished by ATP, Ba2+ and Sr2+. Furthermore, dantrolene and ruthenium red, two classical inhibitors of Ca2+ release from the SR, blocked [3H]-ryanodine binding. Similarly, tetracaine, known to block the charge movement associated with excitation-contraction coupling in vertebrate muscle, inhibited the binding of the alkaloid. Our lobster SR preparation exhibited a single high-affinity ryanodine binding site (Kd = 6.6 nM, Bmax = 10 pmol/mg protein). Since SDS-PAGE of the SR proteins revealed a major band c. 565 kDa which comigrated with the putative ryanodine receptor from both rat and chicken skeletal muscle, we concluded that lobster skeletal muscle is equipped with the 565 kDa ryanodine receptor. Finally, incorporation of the SR microsomal fraction from lobster into planar bilayer membranes revealed the presence of a ryanodine-sensitive Ca2+ channel activity (160 pS in symmetrical 200 mM CsCl solutions). We concluded that both the crustacean and vertebrate skeletal muscle ryanodine receptor share the relevant properties such as molecular weight and affinity for ryanodine and inositol 1,4,5 triphosphate. However, there are important differences between the two receptors including differential effects of the alkaloid on the Ca2+ release channel and modulation of the receptor by nucleotides.","PeriodicalId":18448,"journal":{"name":"Membrane biochemistry","volume":"10 4","pages":"221-35"},"PeriodicalIF":0.0,"publicationDate":"1993-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/09687689309150270","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18524539","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: 13

Inactivation of firefly luciferase and rat erythrocyte ATPase by ultrasound. 萤火虫荧光素酶和大鼠红细胞atp酶的超声失活。

Membrane biochemistry Pub Date : 1993-10-01 DOI: 10.3109/09687689309150269

J C Matthews, W L Harder, W K Richardson, R J Fisher, A M al-Karmi, L A Crum, M A Dinno

{"title":"Inactivation of firefly luciferase and rat erythrocyte ATPase by ultrasound.","authors":"J C Matthews, W L Harder, W K Richardson, R J Fisher, A M al-Karmi, L A Crum, M A Dinno","doi":"10.3109/09687689309150269","DOIUrl":"https://doi.org/10.3109/09687689309150269","url":null,"abstract":"Previous work in our laboratories has shown that, amongst other effects, irradiation of frog skin with low intensity ultrasound causes reductions in the chemical driving force of the short-circuit current. This indicated that either the Na/K dependent ATPase or ATP availability were being reduced. We measured the effect of ultrasound irradiation on ATP and NA/K-dependent ATPase from inverted erythrocyte ghosts and on firefly luciferin and luciferase activity. Our findings demonstrate that ultrasonic cavitation-induced sonochemical reactions were responsible for irreversible inactivation of luciferase and ATPase but had little or no effect on ATP and luciferin. We measured the levels of hydrogen peroxide generated by ultrasound under the conditions of our experiments and found that it could account for only part of the enzyme inactivation observed. Free radical scavengers/antioxidants were capable of fully protecting the enzymes from ultrasound-induced inactivation. These findings demonstrate that, in addition to hydrogen peroxide, free radicals generated by ultrasound are responsible for the effects.","PeriodicalId":18448,"journal":{"name":"Membrane biochemistry","volume":"10 4","pages":"213-20"},"PeriodicalIF":0.0,"publicationDate":"1993-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/09687689309150269","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19002786","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: 6

Uncoupling of occlusion from ATP hydrolysis activity in sarcoplasmic reticulum (Ca2+ + Mg2+)-ATPase. 肌浆网(Ca2+ + Mg2+)-ATP酶ATP水解活性的解偶联闭塞。

Membrane biochemistry Pub Date : 1993-10-01 DOI: 10.3109/09687689309150267

T Lockwich, C D Dunigan, A E Shamoo

{"title":"Uncoupling of occlusion from ATP hydrolysis activity in sarcoplasmic reticulum (Ca2+ + Mg2+)-ATPase.","authors":"T Lockwich, C D Dunigan, A E Shamoo","doi":"10.3109/09687689309150267","DOIUrl":"https://doi.org/10.3109/09687689309150267","url":null,"abstract":"The uncoupling of Ca2+ transport from ATP hydrolysis in the sarcoplasmic reticulum (Ca2+ + Mg2+)-ATPase by trypsin digestion was re-investigated by comparing ATPase activity with the ability of the enzyme to occlude Eu3+ (a transport parameter) after various tryptic digests. With this method, re-examination of uncoupling by tryptic digest of the ATPase revealed that TD2 cleavage (Arg-198) had no effect on either occlusion or ATPase activity. Digestion past TD2 in the presence of 5 mM Ca2+ and at 25 degrees C resulted in the loss of about 70% of the ATPase activity, but no loss of occlusion. Digestion past TD2 in the presence of 5 mM Ca2+, 3 mM ATP, and at 25 degrees C resulted in a partially uncoupled enzyme complex which retained about 50% of the ATPase activity, but completely lost the ability to occlude Eu3+. Digest past TD2 in the presence of 5 mM Ca2+ and 3 mM AMP-PNP (a non-hydrolyzable ATP analog) at 25 degrees C resulted in no loss of occlusion, thus revealing the absolute requirement of ATP during the digest to eliminate occlusion. From these findings we conclude that uncoupling of Ca2+ transport from ATPase activity is possible by tryptic digestion of the (Ca2+ + Mg2+)-ATPase. Interestingly, only after phosphorylation of the enzyme do the susceptible bond(s) which lead to the loss of occlusion become exposed to trypsin.","PeriodicalId":18448,"journal":{"name":"Membrane biochemistry","volume":"10 4","pages":"191-201"},"PeriodicalIF":0.0,"publicationDate":"1993-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/09687689309150267","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19002170","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: 0

Use of the fluorescent probe Laurdan to investigate structural organization of the vesicular stomatitis virus (VSV) membrane. 应用荧光探针Laurdan研究水疱性口炎病毒(VSV)膜的结构组织。

Membrane biochemistry Pub Date : 1993-10-01 DOI: 10.3109/09687689309150268

A Lisi, D Pozzi, S Grimaldi

引用次数: 8

Ca2+ permeability of rat parotid gland basolateral plasma membrane vesicles is modulated by membrane potential and extravesicular [Ca2+]. 大鼠腮腺基底侧质膜囊Ca2+通透性受膜电位和囊外[Ca2+]调节。

Membrane biochemistry Pub Date : 1993-07-01 DOI: 10.3109/09687689309150264

T Lockwich, I S Ambudkar, A E Shamoo

{"title":"Ca2+ permeability of rat parotid gland basolateral plasma membrane vesicles is modulated by membrane potential and extravesicular [Ca2+].","authors":"T Lockwich, I S Ambudkar, A E Shamoo","doi":"10.3109/09687689309150264","DOIUrl":"https://doi.org/10.3109/09687689309150264","url":null,"abstract":"This study examines the Ca2+ permeability of basolateral plasma membrane vesicles (BLMVs) isolated from the rat parotid gland by monitoring the rate of 45Ca2+ efflux from actively-loaded (via the Ca(2+)-ATPase) inside-out BLMVs. Ca2+ efflux from BLMVs into a K(+)-gluconate medium which hyperpolarizes the cytoplasmic side (i.e. outside) of the inside-out BLMVs resulted in a faster rate of Ca2+ efflux compared with a control medium containing N-methyl-D-glucamine (NMDG)-gluconate. Conversely, Ca2+ efflux into a medium which depolarizes the cytoplasmic side of the BLMVs (NMDG-chloride) resulted in slower rates of efflux compared with those observed with the control medium. This increased rate of 45Ca2+ efflux from the hyperpolarized BLMV was inhibited by 1 mM Ni2+, yielding a rate of efflux similar to the rate observed in depolarized BLMVs. The rate of Ca2+ efflux from BLMVs was affected by [Ca2+]o ([Ca2+] on the extravesicular, cytoplasmic side of the vesicle). When [Ca2+]o was kept > 200 nM during efflux, the rate of Ca2+ efflux from both hyper- and depolarized BLMVs was slow and relatively unresponsive to changes in [Ca2+]o, despite sizeable changes in the Ca2+ gradient across the BLMV. However, when [Ca2+]o was lowered < 200 nM, there was an abrupt increase in the rate of Ca2+ efflux from both hyper- and depolarized BLMVs. Additionally, when [Ca2+] was < 200 nM, the rate of Ca2+ efflux appeared to be more sensitive to driving force changes. These data suggest that Ca2+ permeability across the rat parotid gland basolateral plasma membrane is modulated by membrane potential and [Ca2+] on the cytoplasmic side.","PeriodicalId":18448,"journal":{"name":"Membrane biochemistry","volume":"10 3","pages":"171-9"},"PeriodicalIF":0.0,"publicationDate":"1993-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/09687689309150264","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19220673","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

Synthesis of gap junction proteins and collagenases in the preimplantation rat uterus. 大鼠着床前子宫间隙连接蛋白和胶原酶的合成。

Membrane biochemistry Pub Date : 1993-07-01 DOI: 10.3109/09687689309150263

P Anuradha, R V Thampan

引用次数: 4

Allosteric regulation by sodium of the binding of [3H]cocaine and [3H]GBR 12935 to rat and bovine striata. 钠对[3H]可卡因和[3H]GBR 12935与大鼠和牛纹状体结合的变构调节。

Membrane biochemistry Pub Date : 1993-07-01 DOI: 10.3109/09687689309150260

A J Eshleman, D O Calligaro, M E Eldefrawi

{"title":"Allosteric regulation by sodium of the binding of [3H]cocaine and [3H]GBR 12935 to rat and bovine striata.","authors":"A J Eshleman, D O Calligaro, M E Eldefrawi","doi":"10.3109/09687689309150260","DOIUrl":"https://doi.org/10.3109/09687689309150260","url":null,"abstract":"Sodium regulation of ligand binding to the dopamine transporter of rat and/or bovine striata was investigated using a filtration binding assay. In low Na+ phosphate or bicarbonate-buffered sucrose (300 mOsm), the tissue exhibited high affinity for [3H]cocaine which was reduced by the addition of Na+ in a dose-dependent manner. However, [3H]GBR 12935 binding was insensitive to Na+ in these physiological buffers. Although binding of [3H]GBR 12935 was displaced by cocaine in a manner consistent with competitive displacement, a non-linear affinity shift of the displacement of [3H]GBR 12935 by cocaine suggests that the two ligands bind to distinct sites. Binding of both radioligands was suppressed when measured in sodium-free 50 nM Tris-sucrose and increased with the addition of Na+. Scatchard analysis indicated that Bmax for [3H]cocaine binding in Tris plus 120 mM NaCl reached the same level as in the physiological buffers. In Krebs-Ringer buffer with phosphate, bicarbonate or Tris, which contained 120 nM NaCl, both [3H]cocaine and [3H]WIN 35428 binding exhibited lower affinities than in Na(+)-deficient phosphate buffer. It is suggested that the cation form of Tris binds to the dopamine transporter and that the Tris-receptor complex does not bind [3H]cocaine or [3H]GBR 12935. Na+ displaces Tris, forming a Na(+)-receptor complex which binds these ligands. Thus, it is suggested that the Na(+)-dependent binding of cocaine to the dopamine transporter is observed only in Tris.","PeriodicalId":18448,"journal":{"name":"Membrane biochemistry","volume":"10 3","pages":"129-44"},"PeriodicalIF":0.0,"publicationDate":"1993-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/09687689309150260","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19221494","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: 12

Schistosoma mansoni: surface membrane isolation with lectin-coated beads. 曼氏血吸虫:凝集素包被珠表面膜分离。

Membrane biochemistry Pub Date : 1993-07-01 DOI: 10.3109/09687689309150262

F H Pujol, I M Cesari

{"title":"Schistosoma mansoni: surface membrane isolation with lectin-coated beads.","authors":"F H Pujol, I M Cesari","doi":"10.3109/09687689309150262","DOIUrl":"https://doi.org/10.3109/09687689309150262","url":null,"abstract":"Lectins from Lens culinaris and Arachis hypogaea immobilized on polyacrylamide beads were used for selective isolation of glycosylated surface membrane domains of adult Schistosoma mansoni worms, and the method was compared with the membrane isolation procedure developed with polycationic (Affi-Gel) beads. The lentil lectin proved to be suitable for interaction with surface membrane components: an increment in the specific activities of tegumental phosphohydrolases was observed in the bound fraction with respect to that observed in a total worm homogenate. A characteristic polypeptide pattern on gel electrophoresis was also seen, more restricted than that obtained with the bound Affi-Gel fraction. Immobilized peanut lectin was not successful as a method for isolating membrane material from the tegument of adult worms. Solubilization and dissociation of the lentil lectin-bound enzyme markers was achieved after addition of detergent and competing sugars. Glycosylation of the solubilized enzymes was further confirmed by affinity chromatography with fresh lentil lectin-coated beads. These results, together with histochemical evidences, suggest that the active sites of some of these enzymes are located within or close to the cytoplasmic leaflet of the surface tegumental membranes, and allow us to propose a model for the double surface membrane complex where some proteins may be crossing the two bilayers.","PeriodicalId":18448,"journal":{"name":"Membrane biochemistry","volume":"10 3","pages":"155-61"},"PeriodicalIF":0.0,"publicationDate":"1993-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/09687689309150262","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19221499","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: 8

Swelling-stimulated passive potassium transport in camel erythrocytes: inhibitory effects of furosemide and sodium fluoride. 骆驼红细胞肿胀刺激的被动钾转运:速尿和氟化钠的抑制作用。

Membrane biochemistry Pub Date : 1993-07-01 DOI: 10.3109/09687689309150265

N S Gharaibeh, N M Rawashdeh

引用次数: 2