Please wait, while we are loading the content...
Please wait, while we are loading the content...
| Content Provider | PubMed Central |
|---|---|
| Author | Baylor, S. M. Pape, P. C. |
| Abstract | 1. Experiments were carried out on intact, single skeletal muscle fibres from frog in order to estimate the apparent diffusion constant of myoglobin (denoted DAPP) in the myoplasm of living muscle cells. An optical technique was employed to measure myoglobin concentration along the fibre axis following injection of metmyoglobin (denoted metMb) at a point source. The concentration profiles were fitted by the one-dimensional diffusion equation to give estimates of DAPP. The method relied on the fact that myoglobin is normally absent from these frog fibres, thus permitting resolution of the myoglobin-related absorbance above the intrinsic absorbance of the fibre. 2. One complication in the method was that metMb became significantly reduced to oxymyoglobin (denoted MbO2) during the elapsed time before measurement of the concentration profile. The rate of reduction was evaluated by fitting myoglobin-related absorbance spectra, measured at different times following injection of metMb, with in vitro absorbance spectra of metMb and MbO2. Results from four experiments indicated that reduction could be described by a first-order, irreversible reaction having an average rate constant of 0.0164 min-1 (22 degrees C). The effect of reduction on the fitting of DAPP was taken into account. 3. DAPP was determined under three fibre conditions: (1) long sarcomere spacing (3.6-3.8 microns) at 16 degrees C, (2) long sarcomere spacing at 22 degrees C, and (3) normal sarcomere spacing (2.4-2.7 microns) at 22 degrees C. The average values for DAPP under these conditions were: (1) 0.12 (n = 5); (2) 0.17 (n = 5); and (3) 0.15 (n = 7) x 10(-6) cm2 s-1. The average value at 22 degrees C, 0.16 x 10(-6) cm2 s-1, is about 4 times smaller than values for myoglobin diffusivity at 20 degrees C commonly assumed in models of facilitated transport of oxygen by myoglobin. 4. In order to test the possibility that the unexpectedly low value of DAPP found in intact fibres might be due to the binding of myoglobin to relatively immobile sites in myoplasm, experiments were carried out in a cut-fibre preparation using a technique described by Maylie, Irving, Sizto & Chandler (1987 b) for determining the diffusion constants and degree of myoplasmic binding of absorbance dyes. Values for DAPP and the factor (denoted 1 + beta) by which the total myoglobin concentration exceeded the free myoglobin concentration were obtained by fitting the absorbance data by solutions of the one-dimensional diffusion equation.(ABSTRACT TRUNCATED AT 400 WORDS) |
| Ending Page | 275 |
| Starting Page | 247 |
| File Format | |
| ISSN | 14697793 |
| e-ISSN | 14697793 |
| Journal | The Journal of Physiology |
| Volume Number | 406 |
| Language | English |
| Publisher Date | 1988-12-01 |
| 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...
|