Uneven distribution of intracellular Cl- in rat hippocampal neurons.
Electrophysiological observations of neurons suggest that perikarya and dendrites differ in local intracellular Cl- concentration ([Cl-]i), that has not been demonstrated yet. Regional [Cl-]i in cultured hippocampal neurons was estimated using a Cl(-)-sensitive fluorescent dye. Calibration showed that perikaryonic [Cl-]i was lower than dendritic [Cl-]i. Ethacrynic acid, an inhibitor of the outwardly directed Cl(-)-pump, increased the perikaryonic but not dendritic [Cl-]i. A decrease in [Cl-]i induced by furosemide or bumetanide, inhibitors of Na+/K+/2Cl- cotransporters, was more prominent in dendrites than in perikarya. These findings suggest that uneven distribution of Cl- is generated by the region-specific localization of these transporters.
Hara
M
M
Department of Pharmacology, Kansai Medical University, Osaka, Japan.
Inoue
M
M
Yasukura
T
T
Ohnishi
S
S
Mikami
Y
Y
Inagaki
C
C
D000818:Animals; D002034:Bumetanide / Q000494:pharmacology; D002352:Carrier Proteins / Q000037:antagonists & inhibitors; D002712:Chlorides / Q000378:metabolism*; D003712:Dendrites / Q000737:chemistry; D004976:Ethacrynic Acid / Q000494:pharmacology; D005665:Furosemide / Q000494:pharmacology; D006624:Hippocampus / Q000166:cytology* / Q000378:metabolism; D007424:Intracellular Fluid / Q000737:chemistry; D009474:Neurons / Q000737:chemistry* / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar; D028021:Sodium-Potassium-Chloride Symporters
D002352:Carrier Proteins; D002712:Chlorides; D028021:Sodium-Potassium-Chloride Symporters; D002034:Bumetanide; D005665:Furosemide; D004976:Ethacrynic Acid