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| Untersuchte Arbeit: Seite: 10, Zeilen: 6-9, 11-18 |
Quelle: Periasamy und Huke 2001 Seite(n): 1053, Zeilen: li.Sp. 8ff - re.Sp. 1-4 |
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| Muscle contraction is initiated when Ca2+ enters the cell via L-type Ca2+ channels in the plasmalemma and as a consequence, triggers the release of a much larger amount of Ca2+ from the SR via SR Ca2+ release channels (ryanodine receptor) (Fabiato A, 1983; Bers and Perez-Reyes 1999) (Fig: 1.4.1).[...] The free cytosolic Ca2+ concentration determines the extent of the muscle activation and therefore regulates force development. The SR Ca2+ ATPase (SERCA) pumps the Ca2+ back into the SR and is therefore, responsible for muscle relaxation and for replenishing Ca2+ stores needed for the next contraction (MacLennan DH, 1970) (Fig: 4.1.1). SERCA pump activity is regulated by the small, 52-amino acid phosphoprotein phospholamban (PLB), which in its unphosphorylated state lowers the affinity of SERCA for Ca2+ (Simmermann and Jones, 1998).
Bers DM and Perez-Reyes E (1999) Ca channels in cardiac myocytes: structure and function in Ca2+ influx and intracellular Ca2+ release. Cardiovasc Res 42: 339–360. Fabiato A (1983) Calcium-induced release of calcium from the cardiac sarcoplasmic reticulum. Am J Physiol 245: C1–C14. MacLennan DH (1970) Purification and properties of an adenosine triphosphatase from sarcoplasmic reticulum. J Biol Chem 245: 4508–4518. Simmermann HK and Jones LR (1998) Phospholamban: protein structure, mechanism of action, and role in cardiac function. Physiol Rev 78: 921–947. |
Muscle contraction is initiated when Ca2+ enters the cell via L-type Ca2+ channels in the sarcolemma and, as a consequence, triggers the release of a much larger amount of Ca2+ from the SR via SR Ca2+ release channels (ryanodine receptor, RyR).1,2 The free cytosolic Ca2+ concentration determines the extent of muscle activation and therefore regulates force development. The SR Ca2+ ATPase (SERCA) pumps the Ca2+ back into the SR and is therefore responsible for muscle relaxation and for replenishing Ca2+ stores needed for the next contraction.3 SERCA pump activity is regulated by the small 52-aminoacid phosphoprotein phospholamban (PLB), which in its unphosphorylated state lowers the affinity of SERCA for Ca2+.4
1. FABIATO A. Calcium-induced release of calcium from the cardiac sarcoplasmic reticulum. Am J Physiol 1983; 245: C1–C14. 2. BERS DM, PEREZ-REYES E. Ca channels in cardiac myocytes: structure and function in Ca influx and intracellular Ca release. Cardiovasc Res 1999; 42: 339–360. 3. MACLENNAN DH. Purification and properties of an adenosine triphosphatase from sarcoplasmic reticulum. J Biol Chem 1970; 245: 4508–4518. 4. SIMMERMANN HK, JONES LR. Phospholamban: protein structure, mechanism of action, and role in cardiac function. Physiol Rev 1998; 78: 921–947. |
Inkl. Literaturverweise wörtlich übereinstimmend wird ein geschlossener Abschnitt ohne Kennzeichnung übernommen. Einzige Abänderung: aus "sarcolemma" wird das allgemeinere "plasmalemma". Ansonsten erfolgt durch Aa kein Eingriff in den Textkorpus. |
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