Amyloid beta protein-induced irreversible current in rat cortical neurones.
The effect of amyloid beta protein (A beta P) was examined in neurones dissociated from rat cortex using the nystatin perforated patch-clamp technique. A beta P at concentrations > 10 nM induced an irreversible slow inward current associated with an increase in membrane conductance. The time lag until the appearance of the effect of A beta P shortened in a concentration-dependent manner. When extracellular Na+ and Cl-, and intracellular K+ were replaced by equimolar N-methyl glucamine, isothionate- and Cs+, respectively, the membrane conductance and the reversal potential were not affected. Even when an internal solution including 1,2-bis(O-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (20 mM) was used, the effect of A beta P did not alter. It is suggested that A beta P binds to the neuronal membrane and opens non-selective ion channels, resulting in neuronal degeneration.
Furukawa
K
K
Department of Neurophysiology, Tohoku University School of Medicine, Sendai, Japan.
Abe
Y
Y
Akaike
N
N
D016229:Amyloid beta-Peptides / Q000494:pharmacology*; D000818:Animals; D002540:Cerebral Cortex / Q000166:cytology / Q000187:drug effects*; D004553:Electric Conductivity; D007473:Ion Channels / Q000187:drug effects*; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar
D016229:Amyloid beta-Peptides; D007473:Ion Channels