Please wait, while we are loading the content...
Please wait, while we are loading the content...
| Content Provider | PubMed Central |
|---|---|
| Author | Chen, J. Yamada, K. A. Kléber, A. G. Corr, P. B. Yan, G. X. |
| Abstract | 1. The contribution of the concentrating effect due to shrinkage of the extracellular space (ECS) to cellular K+ efflux on extracellular potassium ([K+]o) accumulation in response to ischaemia was investigated in an isolated, blood-perfused rabbit papillary muscle preparation with a confined extracellular space. 2. The ECS was quantified using either of two extracellular markers, choline or tetramethyl ammonium (TMA), each with specific ion-selective electrodes, as well as by measurement of extracellular resistance (ro). [K+]o and [Na+]o were also measured simultaneously using K(+)- and Na(+)-selective electrodes. 3. During ischaemia, [K+]o increased 3-fold from 4.2 +/- 0.1 to 12.6 +/- 1.0 mM at 10 min (n = 10) analogous to changes in the ischaemic heart in vivo. The ECS decreased to 83.9 +/- 3.2% of control measured using 1 mM choline extracellularly (n = 9, P < 0.01) or to 85.7 +/- 0.7% of control using 1 mM TMA (n = 6, P < 0.01). Nearly identical decreases in ro (84.1 +/- 2.4%, n = 15, P < 0.01) occurred simultaneously. 4. The small decrease in the ECS contributed only 0.8-0.9 mM to the total increase in [K+]o of 8.4 mM and had a minor effect on transmembrane K+ flux. No significant differences between the relative changes in [choline] and [Na+]o were observed. This excluded a major transmembrane Na+ movement during early ischaemia. 5. Bumetanide (10 mM), an inhibitor of K(+)-Cl- cotransport, a process which is involved in cell volume regulation consequent to osmotic cell swelling, significantly attenuated the increase in [K+]o after 6 min of ischaemia (8.3 +/- 0.6 mM, n = 5 vs. 10.3 +/- 0.4 mM in the control group, n = 6, P < 0.05), whereas N-ethylmaleimide (1 mM), a stimulator of this cotransporter, augmented [K+]o accumulation (12.0 +/- 0.6 mM at 6 min, P < 0.05). 6. We conclude that during early myocardial ischaemia, a major component of [K+]o accumulation is not caused by diminution of ECS per se, but rather by increased net K+ efflux due in part to K(+)-Cl cotransport secondary to myocyte volume regulation. |
| Starting Page | 215 |
| File Format | |
| ISSN | 14697793 |
| e-ISSN | 14697793 |
| Journal | The Journal of Physiology |
| Issue Number | Pt 1 |
| Volume Number | 490 |
| Language | English |
| Publisher Date | 1996-01-01 |
| Access Restriction | Open |
| Subject Keyword | Research in Higher Education |
| Content Type | Text |
| Resource Type | Article |
| Subject | Physiology Sports Science |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
| Sl. | Authority | Responsibilities | Communication Details |
|---|---|---|---|
| 1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
| 2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
| 3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
| 4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
| 5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
| 6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
| 7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
| 8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
| 9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |
|
Loading...
|