Possible different mechanism between amyloid-beta (25-35)-and substance P-induced chemotaxis of murine microglia.
The mechanism of murine microglial chemotaxis induced by amyloid-beta protein (A beta (25-35)) was investigated. A beta (25-35) dose-dependently stimulated microglial chemotaxis at concentrations between 100 pM and 10 nM. Substance P, a NK-1 agonist, stimulated chemotaxis at concentrations of 10 nM or more. GR-64349, a NK-2 agonist, and senktide, a NK-3 agonist, did not stimulate microglial chemotaxis. We examined whether homologous desensitization of chemotaxis would occur by A beta (25-35). The chemotactic effect of microglia was homologously desensitized by 10 nM A beta (25-35). On the other hand, substance P at 10 nM did not desensitize the A beta (25-35)-induced chemotaxis. These data show that A beta (25-35) induces the chemotaxis of microglia probably through a receptor other than the NK-1 receptor.
Maeda
K
K
Hyogo Institute for Aging Brain and Cognitive Disorders, Saisho-ko Himeji, Japan.
Nakai
M
M
Maeda
S
S
Kawamata
T
T
Yamaguchi
T
T
Tanaka
C
C
D016229:Amyloid beta-Peptides / Q000494:pharmacology* / Q000502:physiology; D000818:Animals; D001921:Brain / Q000166:cytology; D002478:Cells, Cultured; D002633:Chemotaxis / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D017628:Microglia / Q000166:cytology*; D016874:Neurofibrillary Tangles / Q000737:chemistry / Q000378:metabolism; D015288:Neurokinin A / Q000031:analogs & derivatives / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology* / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D013373:Substance P / Q000031:analogs & derivatives / Q000494:pharmacology* / Q000502:physiology
D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C074636:amyloid beta-protein (25-35); C054724:senktide; C068031:neurokinin A (3-10), lysyl(3)-glycyl(8)-R-lactam-leucine(9)-; D013373:Substance P; D015288:Neurokinin A