Swelling-activated chloride currents in embryonic chick heart cells.
OBJECTIVE
To characterize a swelling-activated chloride current, I(Cl, swell), in white Leghorn chick heart cells and the effects of chlorpromazine (CPZ) effects.


METHODS
The patch-clamp technique in the whole-cell configuration was used.


RESULTS
Hyposmotic swelling elicited I(Cl, swell) in white Leghorn chick heart cells. The current amplitude increased from (452 +/- 200) pA to (849 +/- 373) pA with a reduction of osmolarity from 300 mmol.L-1 to 270 mmol.L-1, 4',4-Diisothiocyanostilbene-2,2'-disulphonic acid (DIDS) 100 mumol.L-1 decreased I(Cl, swell) from (1196 +/- 505) pA to (830 +/- 328) pA in hyposmotic solution. In white Leghorn chick heart cells I(Cl, swell) was not induced by CPZ 30 mumol.L-1, which is different from the case of E coli spheroplast.


CONCLUSIONS
Swelling-activated chloride current was activated by hyposmotic swelling in white Leghorn chick heart cells. The mechanism for activating the current is different from that of mechanosensitive ion channels of E coli.
Wei
H
H
Department of Physiology and Biophysics, Liren Laboratory, Fudan University, Shanghai 200433, China.
Mei
Y A
YA
Wu
M M
MM
Sun
J T
JT
Zhou
H Q
HQ
Zhang
Z H
ZH
D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D002642:Chick Embryo; D018118:Chloride Channels / Q000187:drug effects*; D002746:Chlorpromazine / Q000494:pharmacology*; D006321:Heart / Q000502:physiology; D009206:Myocardium / Q000166:cytology*; D018408:Patch-Clamp Techniques
D018118:Chloride Channels; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; D002746:Chlorpromazine