What's the difference between membrane and sarcolemma?
Membrane
Definition:
(n.) A thin layer or fold of tissue, usually supported by a fibrous network, serving to cover or line some part or organ, and often secreting or absorbing certain fluids.
Example Sentences:
(1) Tryptic digestion of the membranes caused complete disappearance of the binding activity, but heat-treatment for 5 min at 70 degrees C caused only 40% loss of activity.
(2) The extents of phospholipid hydrolysis were relatively low in brain homogenates, synaptic plasma membranes and heart ventricular muscle.
(3) The patterns observed were: clusters of granules related to the cell membrane; positive staining localized to portions of the cell membrane, and, less commonly, the whole cell circumference.
(4) Activity of Na,K-ATPase activity was measured as a functional marker for synaptosomal membranes.
(5) The influence of the various concepts for the induction of lateral structure formation in lipid membranes on integral functional units like ionophores is demonstrated by analysing the single channel current fluctuations of gramicidin in bimolecular lipid membranes.
(6) Phospholipid methylation in human EGMs is distinctly different from that in rat EGMs (Hirata and Axelrod 1980) in that the human activity is not Mg++-dependent, and apparent methyltransferase I activity is located in the external membrane surface.
(7) The predicted non-Lorentzian line shapes and widths were found to be in good agreement with experimental results, indicating that the local orientational order (called "packing" by many workers) in the bilayers of small vesicles and in multilamellar membranes is substantially the same.
(8) Apparently, the irradiation with visible light of a low intensity creates an additional proton gradient and thus stimulates a new replication and division cycle in the population of cells whose membranes do not have delta pH necessary for the initiation of these processes.
(9) Using monoclonal antibodies directed against the plasma membrane of Madin-Darby canine kidney (MDCK) cells, we demonstrated previously that a glycoprotein with an Mr = 23,000 (gp23) had a non-polarized cell surface distribution and was observed on both the apical and basolateral membranes (Ojakian, G. K., Romain, R. E., and Herz, R. E. (1987) Am.
(10) The fraction of the viral dose which became cell associated was independent of the incubation temperature and increased with increasing target membrane concentration.
(11) Together these results suggest that IVC may operate as a selective activator of calpain both in the cytosol and at the membrane level; in the latter case in synergism with the activation induced by association of the proteinase to the cell membrane.
(12) The Cole-Moore effect, which was found here only under a specific set of conditions, thus may be a special case rather than the general property of the membrane.
(13) We have examined the insertion of bovine 17 alpha-hydroxylase (P45017 alpha) into the endoplasmic reticulum of COS 1 cells to evaluate the functional role of its hydrophobic amino-terminal sequence and membrane insertion.
(14) The transport of potassium ions through membranes of red blood cells was examined in in bitro experiments using a CMF of 4500 oersted.
(15) These membrane perturbation effects not observed with bleomycin-iron in the presence of a hydroxyl radical scavenger, dimethyl thiourea, or a chelating agent, desferrioxamine, were correlated with the ability of the complex to generate highly reactive oxygen species.
(16) Extensive studies during recent years have shown that the interaction between hormone and membrane-bound receptor can affect the receptor characteristics in at least two ways.
(17) Membranes of this material were filled with islets of Langerhans and implanted in the peritoneal cavity of rats.
(18) The penicillin-resistant Enterococcus hirae R40 has a typical profile of membrane-bound penicillin-binding proteins (PBPs) except that the 71 kDa PBP5 of low penicillin affinity represents about 50% of all the PBPs present.
(19) To investigate the mechanism of enhanced responsiveness of cholesterol-enriched human platelets, we compared stimulation by surface-membrane-receptor (thrombin) and post-receptor (AlF4-) G-protein-directed pathways.
(20) Moreover, in DCVC-treated cells the mitochondria could not be stained with rhodamine-123, indicating severe mitochondrial damage and loss of membrane potential.
Sarcolemma
Definition:
(n.) The very thin transparent and apparently homogeneous sheath which incloses a striated muscular fiber; the myolemma.
Example Sentences:
(1) Three distinct G-proteins have been found in mammalian heart sarcolemma: Gi (alpha i = 40 kDa, beta = 36 kDa, and lambda less than 14 kDa), Gp (alpha p = 23 kDa, beta = 36 kDa, and lambda less than 14 kDa), and Gs (alpha s = 42 kDa).
(2) We found that the Na-Ca exchanger is distributed throughout all membranes in contact with the extracellular space, including the sarcolemma, the transverse tubules (T-tubules), and the intercalated disks.
(3) Here we show that antibodies directed against synthetic peptides and fusion proteins derived from the N-terminal region of human DMD cDNA strongly react with an antigen present in skeletal muscle sarcolemma on cryostat sections of normal human muscle biopsies.
(4) Leucyl-beta-naphthylamidase and gamma-glutamyl transpeptidase showed both cytosol and sarcolemma components.
(5) Ca2+-ATPase of rats and rabbits skeletal muscle sarcolemma was studied as affected by relaxants: tubocurarine, myorelaxin and dioxonium, and by anesthetic fluothane in experiments in vitro and in vivo with lung artificial ventilation during curarization.
(6) The present study tested the hypothesis that a reduction in calcium flux across the sarcolemma or the sarcoplasmic reticulum at the onset of reperfusion could attenuate subsequent mechanical "stunning" (postischemic myocardial dysfunction).
(7) Na, K-ATPase activity of the rat and guinea-pig myocardial sarcolemma and its sensitivity to digoxin (DG) and carbamylcholine (CCh) were investigated during experimental ischemia.
(8) Synthesis of phosphatidylcholine (PC) by S-adenosyl-L-methionine (AdoMet)-dependent methylation of phosphatidylethanolamine (PE) has been recently characterized in rat heart sarcolemma obtained by hypotonic shock-LiBr treatment method.
(9) The rate of nonspecific (non-receptor protein) drug binding to highly purified sarcoplasmic reticulum membranes essentially devoid of specific receptors for these drugs appears to be extremely fast, at least 10(3) times faster than specific drug binding to the receptor in the sarcolemma.
(10) This result suggests that felodipine may inhibity Ca++ release from intracellular Ca++ stores through a mechanism of Ca++ or inositol 1,4,5-triphosphate induced Ca++ release in addition to a blockade of Ca++ influx through the sarcolemma.
(11) An accompanying outward release of protons from localized regions of the sarcolemma (Ca2+ channels?)
(12) These confocal microscopic observations suggest that dystrophin may be localized in a nonuniform, discontinuous pattern along the sarcolemma and in some relationship with the underlying myofibrils.
(13) Employing an enriched cardiac sarcolemma preparation and a (Ca2+, Mg2+)-ATPase fraction isolated from this preparation, this study demonstrates that cholesterol directly interacts with the sarcolemmal calcium pump importantly inhibiting its enzyme activity.
(14) These membranes are identified as being of sarcolemmal origin by enrichment of marker activities associated with the sarcolemma (e.g., binding of the ligands PN 200-110, iodocyanopindolol, and ouabain).
(15) Thick and thin myofilaments appear first in the cell periphery near the sarcolemma.
(16) Kinetic assessment indicated that alpha-agonists led to an increase in the number of electron efflux sites in the ventricular sarcolemma.
(17) This exceeded the maximal endogenous concentrations of 3.2(0.6) nmol long chain fatty acylcarnitine per mg sarcolemma protein observed during myocardial ischaemia.
(18) Subsarcolemmal S1-decorated actin filaments had mixed polarity and attached to the sarcolemma at one end.
(19) This is consistent with the hypothesis that a small net influx of Ca2+ across the sarcolemma during long diastoles was responsible for loading of the reticulum and enhancement of F at low frequencies.
(20) Fast twitch fibres of rat and rabbit show rectangular patterns of intramembrane particles in freeze-fracture preparations of the sarcolemma.