Matches in SemOpenAlex for { <https://semopenalex.org/work/W1483120145> ?p ?o ?g. }
Showing items 1 to 85 of
85
with 100 items per page.
- W1483120145 endingPage "608" @default.
- W1483120145 startingPage "589" @default.
- W1483120145 abstract "ABSTRACT The electrical properties (recorded with intracellular microelectrodes) and the mechanical properties of the myocardium of the wood-louse Porcellio dilatatus (Brandt), a terrestrial isopod crustacean, have been investigated. The diastolic membrane potential varied from – 50 to – 70 mV. Several types of spontaneous electrical responses have been recorded. Their amplitude was usually between 30 and 45 mV and their duration varied from 150 to 400 msec. Except for very rare cases, overshoot did not occur. The phase of depolarization began slowly; it became faster but the maximum rate of rise never exceeded 1– 2 V/sec. The rising phase, devoid of steps, was followed by a partial repolarization leading to a more or less sustained smooth plateau. Superimposed changes of potential occurred very rarely. A jagged appearance of the plateau, as seen in numerous neurogenic hearts and interpreted as junction potentials, could not be observed. During spontaneous activity intracellularly applied currents modified the frequency, the time course and the amplitude of the responses. The junctional nature of the rising phase is suggested. At rest the myocardial membrane displayed a ‘normal’ rectifying property and a weak delayed rectification; in addition, some preparations showed an active graded response of the membrane. A complete regenerative activity was never triggered. A tentative explanation of the electrical response is proposed : the rising phase could chiefly correspond to a junctional potential, the plateau might be a response of the membrane to the synaptic depolarization. The value of the membrane space constant (about 1 mm) suggests that the small muscle fibres, as observed under optical microscope, are interconnected electrically. The impulses delivered by the heart ganglion would activate the whole myocardium almost simultaneously, resulting in a high apparent conduction velocity and a good synchronization from one end to the other. The degree of tension or of relaxation of the fibres closely depended on the value of the membrane voltage. The magnitude of the contraction depended on the absolute level of the potential and the length of time during which the depolarization was maintained. The functional importance of the plateau phase is considered. Intracellular depolarizing pulses led to a contraction of the heart; conversely, hyperpolarizing pulses led to its relaxation. GABA (10− 6 g/ml) inhibited the functioning of the heart and reduced the membrane resistance. Picrotoxin (10−4 g/ml) acted as an antagonist to GABA, L-Glutamic acid (10− 4 g/ml) strongly depolarized the membrane, leading to the cessation of the activity." @default.
- W1483120145 created "2016-06-24" @default.
- W1483120145 creator A5031153848 @default.
- W1483120145 creator A5071871107 @default.
- W1483120145 date "1972-12-01" @default.
- W1483120145 modified "2023-09-29" @default.
- W1483120145 title "Electrophysiology of the Heart of An Isopod Crustacean: <i>Porcellio Dilatatus</i>" @default.
- W1483120145 cites W1984414919 @default.
- W1483120145 cites W2000045723 @default.
- W1483120145 cites W2004517238 @default.
- W1483120145 cites W2009384667 @default.
- W1483120145 cites W2014962123 @default.
- W1483120145 cites W2021591519 @default.
- W1483120145 cites W2024403974 @default.
- W1483120145 cites W2035214132 @default.
- W1483120145 cites W2035268381 @default.
- W1483120145 cites W2035282305 @default.
- W1483120145 cites W2039159511 @default.
- W1483120145 cites W2043012387 @default.
- W1483120145 cites W2048078592 @default.
- W1483120145 cites W2050044443 @default.
- W1483120145 cites W2050118290 @default.
- W1483120145 cites W2057282226 @default.
- W1483120145 cites W2059093744 @default.
- W1483120145 cites W2066345384 @default.
- W1483120145 cites W2071949489 @default.
- W1483120145 cites W2079300439 @default.
- W1483120145 cites W2100833336 @default.
- W1483120145 cites W2111920067 @default.
- W1483120145 cites W2138027098 @default.
- W1483120145 cites W2257667867 @default.
- W1483120145 cites W2378100315 @default.
- W1483120145 cites W4214875640 @default.
- W1483120145 cites W4233417393 @default.
- W1483120145 doi "https://doi.org/10.1242/jeb.57.3.589" @default.
- W1483120145 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/4651660" @default.
- W1483120145 hasPublicationYear "1972" @default.
- W1483120145 type Work @default.
- W1483120145 sameAs 1483120145 @default.
- W1483120145 citedByCount "21" @default.
- W1483120145 crossrefType "journal-article" @default.
- W1483120145 hasAuthorship W1483120145A5031153848 @default.
- W1483120145 hasAuthorship W1483120145A5071871107 @default.
- W1483120145 hasConcept C105702510 @default.
- W1483120145 hasConcept C12554922 @default.
- W1483120145 hasConcept C146403970 @default.
- W1483120145 hasConcept C158494493 @default.
- W1483120145 hasConcept C181911157 @default.
- W1483120145 hasConcept C185263204 @default.
- W1483120145 hasConcept C4141045 @default.
- W1483120145 hasConcept C42407357 @default.
- W1483120145 hasConcept C86803240 @default.
- W1483120145 hasConcept C90856448 @default.
- W1483120145 hasConceptScore W1483120145C105702510 @default.
- W1483120145 hasConceptScore W1483120145C12554922 @default.
- W1483120145 hasConceptScore W1483120145C146403970 @default.
- W1483120145 hasConceptScore W1483120145C158494493 @default.
- W1483120145 hasConceptScore W1483120145C181911157 @default.
- W1483120145 hasConceptScore W1483120145C185263204 @default.
- W1483120145 hasConceptScore W1483120145C4141045 @default.
- W1483120145 hasConceptScore W1483120145C42407357 @default.
- W1483120145 hasConceptScore W1483120145C86803240 @default.
- W1483120145 hasConceptScore W1483120145C90856448 @default.
- W1483120145 hasIssue "3" @default.
- W1483120145 hasLocation W14831201451 @default.
- W1483120145 hasLocation W14831201452 @default.
- W1483120145 hasOpenAccess W1483120145 @default.
- W1483120145 hasPrimaryLocation W14831201451 @default.
- W1483120145 hasRelatedWork W1964804692 @default.
- W1483120145 hasRelatedWork W2023096609 @default.
- W1483120145 hasRelatedWork W2137422361 @default.
- W1483120145 hasRelatedWork W2400752963 @default.
- W1483120145 hasRelatedWork W2502289403 @default.
- W1483120145 hasRelatedWork W2761992323 @default.
- W1483120145 hasRelatedWork W2912579268 @default.
- W1483120145 hasRelatedWork W4210938563 @default.
- W1483120145 hasRelatedWork W4243517488 @default.
- W1483120145 hasRelatedWork W4246509532 @default.
- W1483120145 hasVolume "57" @default.
- W1483120145 isParatext "false" @default.
- W1483120145 isRetracted "false" @default.
- W1483120145 magId "1483120145" @default.
- W1483120145 workType "article" @default.