Please wait, while we are loading the content...
Please wait, while we are loading the content...
| Content Provider | PubMed Central |
|---|---|
| Author | Benson, R. S. P. Sidhu, S. S. Jones, M. N. Case, R. M. Thompson, D. G. |
| Copyright Year | 2002 |
| Abstract | Fatty acids induce cholecystokinin (CCK) secretion both in humans and from murine enteroendocrine cell lines. In both cases, only fatty acids above a critical acyl chain length (C10) are capable of inducing a response. Using the enteroendocrine cell line STC-1, the aim of this study was to determine whether this acyl chain length dependency is related to the fact that longer chain fatty acids are relatively insoluble in aqueous solutions and, if so, whether it is insoluble aggregates of fatty acids rather than free fatty acids which evoke CCK secretion. Solutions of fatty acids (chain length C8–C14), which were judged by filtration and Zeta sizer measurement to contain no fatty acid aggregates, never evoked CCK secretion from STC-1 cells. Filtering fatty acid solutions (of chain length C10, C12 and C14) through polytetrafluoroethylene (PTFE) filters (0.45 μm pore size) revealed a narrow concentration range for each acid over which the amount of fatty acid removed from the solution increased sharply due to the formation of fatty acid aggregates. Filtration experiments, in which suspensions of C10, C12 and C14 fatty acids were passed through pore sizes of 0.2, 0.45 or 1.2 μm, suggested that STC-1 cells did not respond to fatty acid aggregates of greater than 1.2 μm, while at least 50 % of the CCK response was mediated by aggregates which were smaller than 0.45 μm. Fatty acids induce CCK secretion from STC-1 cells by elevating intracellular Ca2+ concentration ([Ca2+]i). We therefore measured the effects on [Ca2+]i of filtered C10, C12 and C14 fatty acids. In all cases, [Ca2+]i responses were closely correlated with CCK secretion. Interestingly, while filtrates of fatty acid solutions evoked CCK secretion and elevated [Ca2+]i, freshly prepared solutions of fatty acids at the same concentration as the filtrates did not. This suggested that fatty acid aggregates were not in equilibrium with the solvent after filtration. The observation that the ability of C10, C12 and C14 filtrates to elevate [Ca2+]i decayed with time was consistent with this hypothesis. Furthermore, sonication of the filtrates abolished their ability to elevate [Ca2+]i. These data further suggest that it is a physical property of the fatty acid solution (the presence of insoluble fatty aggregates) which is responsible for the observed cellular responses. We conclude that Ca2+ mobilisation and CCK secretion in STC-1 cells is driven by a signal transduction mechanism that senses insoluble fatty acid aggregates, rather than free fatty acids in solution. |
| Related Links | http://dx.doi.org/10.1113/jphysiol.2001.012969 |
| Ending Page | 131 |
| Page Count | 11 |
| Starting Page | 121 |
| File Format | |
| ISSN | 00223751 |
| e-ISSN | 14697793 |
| Journal | The Journal of Physiology |
| Issue Number | Pt 1 |
| Volume Number | 538 |
| Language | English |
| Publisher | Blackwell Science Inc |
| Publisher Date | 2002-01-01 |
| Access Restriction | Open |
| Rights Holder | Blackwell Science Inc |
| Subject Keyword | Physiology 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...
|