Beta-amyloid peptide 25-35 regulates basal and hormone-stimulated Ca2+ levels in cultured rat astrocytes.
Beta-amyloid peptide (beta-AP), a characteristic constituent found in senile plaques characteristic for Alzheimer's disease, is neurotoxic by a still largely unknown mechanism. The fragment beta-AP 25-35 induces the full neurotoxic effects. It is important to understand for neurons and astrocytes the influence of beta-AP on Ca2+, a key regulator in cell toxicity and cell damage. Here we examined the effects of acute application of beta-A4 and beta-AP 25-35 on the regulation of cytosolic Ca2+ ([Ca2+]i) in rat astrocytes in primary culture. Transient [Ca2+]i rise in astrocytes induced by a brief stimulation with beta-AP was most probably due to release of Ca2+ from intracellular stores which was exacerbated by reduced extracellular Ca2+ indicating the involvement of receptors sensing extracellular Ca2+. Furthermore, P2 receptor-induced [Ca2+]i oscillations in astrocytes were reversibly interrupted by beta-AP.
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Institut für Neurobiochemie, Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Germany.
Reiser
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G
D000255:Adenosine Triphosphate / Q000494:pharmacology; D016229:Amyloid beta-Peptides / Q000494:pharmacology*; D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D004791:Enzyme Inhibitors / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology*; D010507:Periodicity; D051381:Rats; D017208:Rats, Wistar; D019284:Thapsigargin / Q000494:pharmacology
D016229:Amyloid beta-Peptides; D004791:Enzyme Inhibitors; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40); C074636:amyloid beta-protein (25-35); D019284:Thapsigargin; D000255:Adenosine Triphosphate; D002118:Calcium