Loading...
Please wait, while we are loading the content...
Similar Documents
Ca2+ influx through stretch-activated cation channels activates maxi K+ channels in porcine endocardial endothelium.
| Content Provider | Semantic Scholar |
|---|---|
| Author | Hoyer, Joachim Distler, Armin Haase, Winfried Gögelein, Heinz |
| Copyright Year | 1994 |
| Abstract | The endocardial endothelium is an important modulator of myocardial function. The present study demonstrates the existence of a stretch-activated Ca(2+)-permeable cation channel and of a Ca(2+)-activated K+ channel in the endocardial endothelium of the porcine right atrium. The stretch-activated channel is permeable for K+, Na+, Ca2+, and Ba2+, with mean conductances of approximately 32 pS for the monovalent cations and approximately 13 pS for divalent cations. The Ca(2+)-activated K+ channel has a mean conductance of 192 pS in symmetrical KCl. solution. Channel activity is strongly dependent on membrane potential and the cytosolic Ca2+ concentration. Half-maximal activation occurs at a cytosolic Ca2+ concentration of approximately 5 microM. The influx of Ca2+ through the stretch-activated channel is sufficient to activate the Ca(2+)-activated K+ channel in cell-attached patches. Upon activation of the stretch-activated channel, the cytosolic Ca2+ concentration increases, at least locally, to values of approximately 0.5 microM, as deduced from the open probability of the Ca(2+)-dependent K+ channel that was activated simultaneously. The stretch-activated channels are capable of inducing an intracellular Ca2+ signal and may have a role as mechanosensors in the atrial endothelium, possibly activated by atrial overload. |
| File Format | PDF HTM / HTML |
| DOI | 10.1073/pnas.91.6.2367 |
| Alternate Webpage(s) | http://www.pnas.org/content/91/6/2367.full.pdf?origin=publication_detail |
| PubMed reference number | 7510889 |
| Alternate Webpage(s) | https://doi.org/10.1073/pnas.91.6.2367 |
| Journal | Medline |
| Volume Number | 91 |
| Issue Number | 6 |
| Journal | Proceedings of the National Academy of Sciences of the United States of America |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
