Ion Transport by the Na-Ca Exchange in Isolated Rod Outer Segments
The inward membrane current generated by the coupled exchange of external sodium for internal calcium has been investigated in isolated rod outer segments. The exchange rate is sensitive to voltage, with a reduction by a factor of e occurring for a 70-mV depolarization in normal Ringer's soluti...
Gespeichert in:
| Veröffentlicht in: | Proceedings of the National Academy of Sciences - PNAS 1988-06, Vol.85 (12), p.4548-4552 |
|---|---|
| Hauptverfasser: | , , |
| Format: | Artikel |
| Sprache: | eng |
| Schlagworte: | |
| Online-Zugang: | Volltext |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| container_end_page | 4552 |
|---|---|
| container_issue | 12 |
| container_start_page | 4548 |
| container_title | Proceedings of the National Academy of Sciences - PNAS |
| container_volume | 85 |
| creator | Lagnado, L. Cervetto, L. McNaughton, P. A. |
| description | The inward membrane current generated by the coupled exchange of external sodium for internal calcium has been investigated in isolated rod outer segments. The exchange rate is sensitive to voltage, with a reduction by a factor of e occurring for a 70-mV depolarization in normal Ringer's solution. The voltage sensitivity is not a constant property of the exchange, as it is reduced by an increase in external Na+ or by the removal of external Ca2+, Mg2+, or K+. Changes in membrane potential do not appear to affect the affinity of the exchange mechanism for internal Ca2+, but hyperpolarization increases the affinity for external Na+. When the external Na+ concentration is raised sufficiently to saturate the exchange mechanism, the voltage sensitivity is no longer apparent. We propose that the voltage dependence of the exchange is due to the external Na+-binding site being sensitive to membrane potential, perhaps because it is located within the membrane electric field. |
| doi_str_mv | 10.1073/pnas.85.12.4548 |
| format | Article |
| fullrecord | <record><control><sourceid>jstor_pnas_</sourceid><recordid>TN_cdi_pnas_primary_85_12_4548</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><jstor_id>31819</jstor_id><sourcerecordid>31819</sourcerecordid><originalsourceid>FETCH-LOGICAL-c438t-e031ba10fe0e6f107ec6a7aa546ce837982bb1c2c515bbd69a589cb3b1de44cc3</originalsourceid><addsrcrecordid>eNqFkEtLAzEURoMotT7WgqBkpatp85pMZqnFR6FY0LoOSeaOtkxnapIB_fdOaVXc6OouvnO_ezkInVAyoCTjw1VtwkClA8oGIhVqB_UpyWkiRU52UZ8QliVKMLGPDkJYEELyVJEe6nGuiCKyj67HTY1n3tRh1fiI7QeOr4AfTDIy-ObdvZr6BfC8xuPQVCZCgR-bAk_bCB4_wcsS6hiO0F5pqgDH23mInm9vZqP7ZDK9G4-uJokTXMUECKfWUFICAVl2z4OTJjMmFdKB4lmumLXUMZfS1NpC5iZVubPc0gKEcI4footN78o3by2EqJfz4KCqTA1NG3SmmFSSsn9BKnIumco6cLgBnW9C8FDqlZ8vjf_QlOi1Xr3Wq1WqKdNrvd3G2ba6tUsovvmtzy4_3-brxa_0V8Hln4Au26qK8B478nRDLkJs_M8lqmjOPwHT_ZXy</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>14936287</pqid></control><display><type>article</type><title>Ion Transport by the Na-Ca Exchange in Isolated Rod Outer Segments</title><source>Jstor Complete Legacy</source><source>MEDLINE</source><source>PubMed Central</source><source>Alma/SFX Local Collection</source><source>Free Full-Text Journals in Chemistry</source><creator>Lagnado, L. ; Cervetto, L. ; McNaughton, P. A.</creator><creatorcontrib>Lagnado, L. ; Cervetto, L. ; McNaughton, P. A.</creatorcontrib><description>The inward membrane current generated by the coupled exchange of external sodium for internal calcium has been investigated in isolated rod outer segments. The exchange rate is sensitive to voltage, with a reduction by a factor of e occurring for a 70-mV depolarization in normal Ringer's solution. The voltage sensitivity is not a constant property of the exchange, as it is reduced by an increase in external Na+ or by the removal of external Ca2+, Mg2+, or K+. Changes in membrane potential do not appear to affect the affinity of the exchange mechanism for internal Ca2+, but hyperpolarization increases the affinity for external Na+. When the external Na+ concentration is raised sufficiently to saturate the exchange mechanism, the voltage sensitivity is no longer apparent. We propose that the voltage dependence of the exchange is due to the external Na+-binding site being sensitive to membrane potential, perhaps because it is located within the membrane electric field.</description><identifier>ISSN: 0027-8424</identifier><identifier>EISSN: 1091-6490</identifier><identifier>DOI: 10.1073/pnas.85.12.4548</identifier><identifier>PMID: 3380806</identifier><language>eng</language><publisher>United States: National Academy of Sciences of the United States of America</publisher><subject>Ambystoma tigrinum ; Animals ; antiport ; calcium ; Calcium - metabolism ; Carrier Proteins - metabolism ; Cell membranes ; Electric Conductivity ; Electric current ; Electric fields ; Electric potential ; Exchange rates ; In Vitro Techniques ; membrane currents ; Membrane potential ; Membrane Potentials ; P branes ; Photoreceptor Cells - physiology ; Pipettes ; Rod Cell Outer Segment - physiology ; rod outer segment membranes ; sodium ; Sodium - metabolism ; Sodium-Calcium Exchanger ; Stoichiometry ; Surgical suction ; Urodela</subject><ispartof>Proceedings of the National Academy of Sciences - PNAS, 1988-06, Vol.85 (12), p.4548-4552</ispartof><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c438t-e031ba10fe0e6f107ec6a7aa546ce837982bb1c2c515bbd69a589cb3b1de44cc3</citedby></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Uhttp://www.pnas.org/content/85/12.cover.gif</thumbnail><linktopdf>$$Uhttps://www.jstor.org/stable/pdf/31819$$EPDF$$P50$$Gjstor$$H</linktopdf><linktohtml>$$Uhttps://www.jstor.org/stable/31819$$EHTML$$P50$$Gjstor$$H</linktohtml><link.rule.ids>314,776,780,799,27901,27902,57992,58225</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/3380806$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Lagnado, L.</creatorcontrib><creatorcontrib>Cervetto, L.</creatorcontrib><creatorcontrib>McNaughton, P. A.</creatorcontrib><title>Ion Transport by the Na-Ca Exchange in Isolated Rod Outer Segments</title><title>Proceedings of the National Academy of Sciences - PNAS</title><addtitle>Proc Natl Acad Sci U S A</addtitle><description>The inward membrane current generated by the coupled exchange of external sodium for internal calcium has been investigated in isolated rod outer segments. The exchange rate is sensitive to voltage, with a reduction by a factor of e occurring for a 70-mV depolarization in normal Ringer's solution. The voltage sensitivity is not a constant property of the exchange, as it is reduced by an increase in external Na+ or by the removal of external Ca2+, Mg2+, or K+. Changes in membrane potential do not appear to affect the affinity of the exchange mechanism for internal Ca2+, but hyperpolarization increases the affinity for external Na+. When the external Na+ concentration is raised sufficiently to saturate the exchange mechanism, the voltage sensitivity is no longer apparent. We propose that the voltage dependence of the exchange is due to the external Na+-binding site being sensitive to membrane potential, perhaps because it is located within the membrane electric field.</description><subject>Ambystoma tigrinum</subject><subject>Animals</subject><subject>antiport</subject><subject>calcium</subject><subject>Calcium - metabolism</subject><subject>Carrier Proteins - metabolism</subject><subject>Cell membranes</subject><subject>Electric Conductivity</subject><subject>Electric current</subject><subject>Electric fields</subject><subject>Electric potential</subject><subject>Exchange rates</subject><subject>In Vitro Techniques</subject><subject>membrane currents</subject><subject>Membrane potential</subject><subject>Membrane Potentials</subject><subject>P branes</subject><subject>Photoreceptor Cells - physiology</subject><subject>Pipettes</subject><subject>Rod Cell Outer Segment - physiology</subject><subject>rod outer segment membranes</subject><subject>sodium</subject><subject>Sodium - metabolism</subject><subject>Sodium-Calcium Exchanger</subject><subject>Stoichiometry</subject><subject>Surgical suction</subject><subject>Urodela</subject><issn>0027-8424</issn><issn>1091-6490</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>1988</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><recordid>eNqFkEtLAzEURoMotT7WgqBkpatp85pMZqnFR6FY0LoOSeaOtkxnapIB_fdOaVXc6OouvnO_ezkInVAyoCTjw1VtwkClA8oGIhVqB_UpyWkiRU52UZ8QliVKMLGPDkJYEELyVJEe6nGuiCKyj67HTY1n3tRh1fiI7QeOr4AfTDIy-ObdvZr6BfC8xuPQVCZCgR-bAk_bCB4_wcsS6hiO0F5pqgDH23mInm9vZqP7ZDK9G4-uJokTXMUECKfWUFICAVl2z4OTJjMmFdKB4lmumLXUMZfS1NpC5iZVubPc0gKEcI4footN78o3by2EqJfz4KCqTA1NG3SmmFSSsn9BKnIumco6cLgBnW9C8FDqlZ8vjf_QlOi1Xr3Wq1WqKdNrvd3G2ba6tUsovvmtzy4_3-brxa_0V8Hln4Au26qK8B478nRDLkJs_M8lqmjOPwHT_ZXy</recordid><startdate>19880601</startdate><enddate>19880601</enddate><creator>Lagnado, L.</creator><creator>Cervetto, L.</creator><creator>McNaughton, P. A.</creator><general>National Academy of Sciences of the United States of America</general><general>National Acad Sciences</general><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>8FD</scope><scope>FR3</scope><scope>M7Z</scope><scope>P64</scope><scope>7X8</scope></search><sort><creationdate>19880601</creationdate><title>Ion Transport by the Na-Ca Exchange in Isolated Rod Outer Segments</title><author>Lagnado, L. ; Cervetto, L. ; McNaughton, P. A.</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c438t-e031ba10fe0e6f107ec6a7aa546ce837982bb1c2c515bbd69a589cb3b1de44cc3</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>1988</creationdate><topic>Ambystoma tigrinum</topic><topic>Animals</topic><topic>antiport</topic><topic>calcium</topic><topic>Calcium - metabolism</topic><topic>Carrier Proteins - metabolism</topic><topic>Cell membranes</topic><topic>Electric Conductivity</topic><topic>Electric current</topic><topic>Electric fields</topic><topic>Electric potential</topic><topic>Exchange rates</topic><topic>In Vitro Techniques</topic><topic>membrane currents</topic><topic>Membrane potential</topic><topic>Membrane Potentials</topic><topic>P branes</topic><topic>Photoreceptor Cells - physiology</topic><topic>Pipettes</topic><topic>Rod Cell Outer Segment - physiology</topic><topic>rod outer segment membranes</topic><topic>sodium</topic><topic>Sodium - metabolism</topic><topic>Sodium-Calcium Exchanger</topic><topic>Stoichiometry</topic><topic>Surgical suction</topic><topic>Urodela</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Lagnado, L.</creatorcontrib><creatorcontrib>Cervetto, L.</creatorcontrib><creatorcontrib>McNaughton, P. A.</creatorcontrib><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>Technology Research Database</collection><collection>Engineering Research Database</collection><collection>Biochemistry Abstracts 1</collection><collection>Biotechnology and BioEngineering Abstracts</collection><collection>MEDLINE - Academic</collection><jtitle>Proceedings of the National Academy of Sciences - PNAS</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Lagnado, L.</au><au>Cervetto, L.</au><au>McNaughton, P. A.</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Ion Transport by the Na-Ca Exchange in Isolated Rod Outer Segments</atitle><jtitle>Proceedings of the National Academy of Sciences - PNAS</jtitle><addtitle>Proc Natl Acad Sci U S A</addtitle><date>1988-06-01</date><risdate>1988</risdate><volume>85</volume><issue>12</issue><spage>4548</spage><epage>4552</epage><pages>4548-4552</pages><issn>0027-8424</issn><eissn>1091-6490</eissn><abstract>The inward membrane current generated by the coupled exchange of external sodium for internal calcium has been investigated in isolated rod outer segments. The exchange rate is sensitive to voltage, with a reduction by a factor of e occurring for a 70-mV depolarization in normal Ringer's solution. The voltage sensitivity is not a constant property of the exchange, as it is reduced by an increase in external Na+ or by the removal of external Ca2+, Mg2+, or K+. Changes in membrane potential do not appear to affect the affinity of the exchange mechanism for internal Ca2+, but hyperpolarization increases the affinity for external Na+. When the external Na+ concentration is raised sufficiently to saturate the exchange mechanism, the voltage sensitivity is no longer apparent. We propose that the voltage dependence of the exchange is due to the external Na+-binding site being sensitive to membrane potential, perhaps because it is located within the membrane electric field.</abstract><cop>United States</cop><pub>National Academy of Sciences of the United States of America</pub><pmid>3380806</pmid><doi>10.1073/pnas.85.12.4548</doi><tpages>5</tpages><oa>free_for_read</oa></addata></record> |
| fulltext | fulltext |
| identifier | ISSN: 0027-8424 |
| ispartof | Proceedings of the National Academy of Sciences - PNAS, 1988-06, Vol.85 (12), p.4548-4552 |
| issn | 0027-8424 1091-6490 |
| language | eng |
| recordid | cdi_pnas_primary_85_12_4548 |
| source | Jstor Complete Legacy; MEDLINE; PubMed Central; Alma/SFX Local Collection; Free Full-Text Journals in Chemistry |
| subjects | Ambystoma tigrinum Animals antiport calcium Calcium - metabolism Carrier Proteins - metabolism Cell membranes Electric Conductivity Electric current Electric fields Electric potential Exchange rates In Vitro Techniques membrane currents Membrane potential Membrane Potentials P branes Photoreceptor Cells - physiology Pipettes Rod Cell Outer Segment - physiology rod outer segment membranes sodium Sodium - metabolism Sodium-Calcium Exchanger Stoichiometry Surgical suction Urodela |
| title | Ion Transport by the Na-Ca Exchange in Isolated Rod Outer Segments |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-02-05T08%3A39%3A07IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-jstor_pnas_&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Ion%20Transport%20by%20the%20Na-Ca%20Exchange%20in%20Isolated%20Rod%20Outer%20Segments&rft.jtitle=Proceedings%20of%20the%20National%20Academy%20of%20Sciences%20-%20PNAS&rft.au=Lagnado,%20L.&rft.date=1988-06-01&rft.volume=85&rft.issue=12&rft.spage=4548&rft.epage=4552&rft.pages=4548-4552&rft.issn=0027-8424&rft.eissn=1091-6490&rft_id=info:doi/10.1073/pnas.85.12.4548&rft_dat=%3Cjstor_pnas_%3E31819%3C/jstor_pnas_%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_pqid=14936287&rft_id=info:pmid/3380806&rft_jstor_id=31819&rfr_iscdi=true |