Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1975-11-7
pubmed:abstractText
The complement component, C5a provokes the selective release of granule-associated enzymes from the intact, viable cytochalasin B-treated human polymorphonuclear leukocytes (PMN) in the absence of phagocytosis or cellular adherence to surfaces. Consquently, in this experimental system the influence of divalent cations on these two processes can be disregarded and their effects on enzymes secretion can be studied directly. Cytochalasin B-treated PMN exposed to C5a in calcium and magnesium-free media consistently secreted significant amounts of the granule-associated enzymes, beta-glucuronidase and lysozyme. The basal secretory response was not diminished if cells were preincubated with 5.0 mM EDTA, nor was it influenced if 1.0 mm or 2.0 mM EDTA were present in the reaction mixtures. The addition of calcium (up to 1.5 to 2.0 mM) produced a concentration-dependent enhancement of beta-glucuronidase release, whereas increasing amounts of calcium (above 2.0 mM) inhibited secretion of this enzyme. Lysozyme release was similarly enhanced by the addition of calcium, but inhibition with high concentrations was not observed. Calcium per se, in the absence of C5a, provoked only the release of lysozyme from these cells. The effects of calcium upon enzyme release were not associated with alterations in the state of assembly of cytoplasmic microtubules. These findings provide another example of the role of calcium in "stimulus-secretion coupling" and provide evidence that exocytosis of various granules in human PMN is regulated by independent mechanisms involving calcium.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:volume
115
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
665-70
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:1151072-Adult, pubmed-meshheading:1151072-Calcium, pubmed-meshheading:1151072-Cations, Divalent, pubmed-meshheading:1151072-Cell Adhesion, pubmed-meshheading:1151072-Complement C5, pubmed-meshheading:1151072-Complement System Proteins, pubmed-meshheading:1151072-Cytochalasin B, pubmed-meshheading:1151072-Dimethyl Sulfoxide, pubmed-meshheading:1151072-Glucuronates, pubmed-meshheading:1151072-Glucuronidase, pubmed-meshheading:1151072-Granulocytes, pubmed-meshheading:1151072-Humans, pubmed-meshheading:1151072-L-Lactate Dehydrogenase, pubmed-meshheading:1151072-Leukocytes, pubmed-meshheading:1151072-Micrococcus, pubmed-meshheading:1151072-Microscopy, Electron, pubmed-meshheading:1151072-Microtubules, pubmed-meshheading:1151072-Muramidase, pubmed-meshheading:1151072-Phagocytosis, pubmed-meshheading:1151072-Phenolphthaleins
pubmed:year
1975
pubmed:articleTitle
Influence of divalent cations upon complement-mediated enzyme release from human polymorphonuclear leukocytes.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.