Induction of calcium release from sarcoplasmic reticulum of skeletal muscle by xanthone and norathyriol
| Autor: | Che-Ming Teng, Y W. Cheng, Jaw Jou Kang, Feng‐Nien ‐N Ko, Min-Liang Kuo, C.N. Lin |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Male
medicine.medical_specialty Ruthenium red Phosphodiesterase Inhibitors Xanthones Diaphragm Muscle Proteins chemistry.chemical_element Calcium-Transporting ATPases In Vitro Techniques Calcium Potassium Chloride Mice chemistry.chemical_compound Caffeine Internal medicine Xanthone medicine Animals Magnesium Muscle Skeletal Pharmacology Mice Inbred ICR Voltage-dependent calcium channel Ryanodine Chemistry Ryanodine receptor Endoplasmic reticulum Skeletal muscle Ruthenium Red Sarcoplasmic Reticulum Endocrinology medicine.anatomical_structure Xanthenes Biophysics Female Calcium Channels Rabbits medicine.symptom Muscle Contraction Research Article Muscle contraction |
| Zdroj: | British Journal of Pharmacology. 118:1736-1742 |
| ISSN: | 0007-1188 |
| Popis: | 1. Effects of xanthone and its derivative, 1,3,6,7-tetrahydroxyxanthone (norathyriol), on Ca2+ release and ryanodine binding were studied in isolated sarcoplasmic reticulum (SR) vesicles from rabbit skeletal muscle. 2. Both xanthone and norathyriol dose-dependently induced Ca2+ release from the actively loaded SR vesicles which was blocked by ruthenium red, a specific Ca2+ release inhibitor, and Mg2+. 3. Xanthone and norathyriol also dose-dependently increased apparent [3H]-ryanodine binding. Norathyriol, but not xanthone, produced a synergistic effect on binding activation when added concurrently with caffeine. 4. In the presence of Mg2+, which inhibits ryanodine binding, both caffeine and norathyriol, but not xanthone, could restore the binding to the level observed in the absence of Mg2+. 5. Xanthone activated the Ca(2+)-ATPase activity of isolated SR vesicles dose-dependently reaching 70% activation at 300 microM. 6. When tested in mouse diaphragm, norathyriol potentiated the muscle contraction followed by twitch depression and contracture in either a Ca(2+) -free bathing solution or one containing 2.5 mM Ca2+. These norathyriol-induced effects on muscle were inhibited by pretreatment with ruthenium red or ryanodine. 7. These data suggest that xanthone and norathyriol can induce Ca2+ release from the SR of skeletal muscle through a direct interaction with the Ca2+ release channel, also known as the ryanodine receptor. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text