Amino acid-permeable anion channels in early mouse embryos and their possible effects on cleavage
Sonoda, M; Okamoto, F; Kajiya, H; Inoue, Y; Honjo, K; Sumii, Y; Kawarabayashi, T; Okabe, K
HERO ID
2789478
Reference Type
Journal Article
Year
2003
Language
English
PMID
| HERO ID | 2789478 |
|---|---|
| In Press | No |
| Year | 2003 |
| Title | Amino acid-permeable anion channels in early mouse embryos and their possible effects on cleavage |
| Authors | Sonoda, M; Okamoto, F; Kajiya, H; Inoue, Y; Honjo, K; Sumii, Y; Kawarabayashi, T; Okabe, K |
| Journal | Biology of Reproduction |
| Volume | 68 |
| Issue | 3 |
| Page Numbers | 947-953 |
| Abstract | Effects of several Cl(-) channel blockers on ionic currents in mouse embryos were studied using whole-cell patch-clamp and microelectrode methods. Microelectrode measurements showed that the resting membrane potential of early embryonic cells (1-cell stage) was -23 mV and that reduction of extracellular Cl(-) concentration depolarized the membrane, suggesting that Cl(-) conductance is a major contributor for establishing the resting membrane potential. Membrane currents recorded by whole-cell voltage clamp showed outward rectification and confirmed that a major component of these embryonic currents are carried by Cl(-) ions. A Cl(-) channel blocker, 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), suppressed the outward rectifier current in a voltage- and concentration-dependent manner. Other Cl(-) channel blockers (5-nitro-2-[3-phenylpropyl-amino] benzoic acid and 2-[3-(trifluoromethyl)-anilino] nicotinic acid [niflumic acid]) similarly inhibited this current. Simultaneous application of niflumic acid with DIDS further suppressed the outward rectifier current. Under high osmotic condition, niflumic acid, but not DIDS, inhibited the Cl(-)current, suggesting the presence of two types of Cl(-) channels: a DIDS-sensitive (swelling-activated) channel, and a DIDS-insensitive (niflumic acid-sensitive) Cl(-) channel. Anion permeability of the DIDS-insensitive Cl(-) current differed from that of the compound Cl(-) current: Rank order of anion permeability of the DIDS-sensitive Cl(-) channels was I(-) = Br(-) > Cl(-) > gluconate(-), whereas that of the DIDS-insensitive Cl(-) channel was I(-) = Br(-) > Cl(-) > gluconate(-). These results indicate that early mouse embryos have a Cl(-) channel that is highly permeable to amino acids, which may regulate intracellular amino acid concentration. |
| Doi | 10.1095/biolreprod.102.007088 |
| Pmid | 12604647 |
| Wosid | WOS:000181212400031 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Language Text | English |
| Keyword | developmental biology; early development; embryo |