Human platelet calcium mobilisation in response to beta-amyloid (25-35): buffer dependency and unchanged response in Alzheimer's disease.
In the present study, the effects of beta-amyloid (25-35) (Abeta (25-35)) upon calcium signalling by the human platelet has been investigated. When assays were conducted using HEPES buffers, Abeta (25-35), but not the inactive peptide Abeta (35-25), produced a robust increase in intracellular calcium that remained after removal of extracellular calcium but was abolished by the phospholipase C inhibitor U-73122. There was no significant difference between the calcium response to Abeta (25-35) in platelets from patients with Alzheimer's disease and from age-matched controls. In contrast to the robust effects on calcium mobilisation in HEPES buffers, very little calcium response to Abeta (25-35) was seen when Krebs (pH 7.8) buffer was used.
Hedin
H L
HL
Department of Pharmacology and Clinical Neuroscience, Umeå University, SE-901 87, Umeå, Sweden. henrietta.hedin@pharm.umu.se
Eriksson
S
S
Fowler
C J
CJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood*; D016229:Amyloid beta-Peptides / Q000494:pharmacology*; D001692:Biological Transport / Q000187:drug effects; D001792:Blood Platelets / Q000378:metabolism*; D002021:Buffers; D002118:Calcium / Q000378:metabolism*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D004963:Estrenes / Q000494:pharmacology; D005110:Extracellular Space / Q000378:metabolism; D005260:Female; D006531:HEPES / Q000494:pharmacology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D010446:Peptide Fragments / Q000494:pharmacology*; D011760:Pyrrolidinones / Q000494:pharmacology; D012016:Reference Values; D012701:Serotonin / Q000494:pharmacology
D016229:Amyloid beta-Peptides; D002021:Buffers; D002121:Calcium Channel Blockers; D004963:Estrenes; D010446:Peptide Fragments; D011760:Pyrrolidinones; C074636:amyloid beta-protein (25-35); C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; D012701:Serotonin; D006531:HEPES; D002118:Calcium