title: S-100ab increases Ca2+ release in purified sarcoplasmic reticulum vesicles of frog skeletal muscle.
abstract: The S-100ab protein, a mixed isoform member of the S-100 family, stimulates Ca(2+)-induced Ca(2+)-release from sarcoplasmic reticulum vesicles purified from frog skeletal muscle cells. The effects of S-100ab appear to be specific and result from its peculiar characteristics rather than the fact that it is a calcium-binding protein. Moreover, the addition of S-100ab to the solution completely abolished the inhibition provoked when Ruthenium Red was added alone. Experiments that added labelled Ryanodine with and without S-100 indicated that the protein diminished the affinity of the alkaloid at its receptor site.
mesh_terms: D000818:Animals; D015415:Biomarkers; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000187:drug effects* / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000502:physiology*; D002417:Cattle; D009119:Muscle Contraction; D009132:Muscles / Q000648:ultrastructure; D009414:Nerve Growth Factors; D011898:Ranidae / Q000378:metabolism; D012430:Ruthenium Red / Q000494:pharmacology; D012433:Ryanodine / Q000494:pharmacology; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000494:pharmacology*; D012519:Sarcoplasmic Reticulum / Q000187:drug effects* / Q000378:metabolism
chemical_list: D015415:Biomarkers; D015220:Calcium Channels; D002135:Calcium-Binding Proteins; D009414:Nerve Growth Factors; C030564:S-100 calcium-binding protein alpha subunit; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; D012430:Ruthenium Red; D012433:Ryanodine; D002118:Calcium