T-Type Calcium Current and Calcium-Induced Calcium-Release in Developing Chick Myocardium
| dc.contributor.author | Kitchens, Susan A. | |
| dc.date.accessioned | 2015-03-19T01:43:51Z | en |
| dc.date.available | 2015-03-19T01:43:51Z | en |
| dc.date.issued | 2002-02 | en |
| dc.identifier.uri | http://hdl.handle.net/10675.2/346854 | |
| dc.description.abstract | HYPOTHESES 1. The contribution of T-type calcium currents to the calcium transient are greater at young developmental ages, but decline with chick heart development. The decrease in contribution of T-type calcium current to the calcium transient mirrors the normal developmental reduction in magnitude of T-type current in the chick heart. 2. T-type calcium current plays a role in calcium-induced calcium-release during chick heart development. T-type current plays a significant role in the calcium-induced calcium-release process in younger embryos due to the greater magnitude of the current at earlier developmental stages. 3. More than one isoform of the T-type calcium channel is present in developing chick myocardium. The multiple isoforms will function concomitantly to provide sufficient T-type calcium current for proper development. 4. The expression of the T-type calcium channel in ventricle decreases with development. There is a concomitant decrease in T-type Ca2* current stimulation of CICR. SPECIFIC AIMS 1. To determine the contribution of T-type calcium current to the calcium transient during development in chick ventricular myocytes. The approach is to use a fluorescent calcium indicator to measure the transients from myocytes at embryonic day (ED) 5, EDI 1 andED15. 2. To determine the contribution of T-type calcium current to calcium-induced calciumrelease during chick heart development. The approach is to use pharmacological agents to quantify the contribution to the Ca3* transient from T-type Ca3* current stimulated CICR. 3. To determine which isoforms of the T-type calcium channel are likely to be present in chick myocardium. The approach is to use PCR methods to identify any T-type channel isoform mRNA expressed in chick ventricle. 4. To determine the level of expression of T-type calcium channel isoforms during the development of chick ventricle. The approach is to use molecular quantitation methods to examine the expression pattern of T-type channel isoforms in chick ventricle during development. | |
| dc.relation.url | http://search.proquest.com/docview/276271918?accountid=12365 | en |
| dc.rights | Copyright protected. Unauthorized reproduction or use beyond the exceptions granted by the Fair Use clause of U.S. Copyright law may violate federal law. | en |
| dc.subject | Cardiac Function | en |
| dc.subject | Excitation-contraction Coupling | en |
| dc.subject | Cellular Structures | en |
| dc.subject | Calcium Entry and Release Mechanisms | en |
| dc.subject | Calcium Currents | en |
| dc.subject | Developmental Changes | en |
| dc.title | T-Type Calcium Current and Calcium-Induced Calcium-Release in Developing Chick Myocardium | en |
| dc.type | Dissertation | en |
| dc.contributor.department | Department of Cellular Biology and Anatomy | en |
| dc.description.advisor | Not Listed | en |
| dc.description.degree | Doctor of Philosophy (Ph.D.) | en |
| dc.description.committee | Not Listed | en |
| html.description.abstract | HYPOTHESES 1. The contribution of T-type calcium currents to the calcium transient are greater at young developmental ages, but decline with chick heart development. The decrease in contribution of T-type calcium current to the calcium transient mirrors the normal developmental reduction in magnitude of T-type current in the chick heart. 2. T-type calcium current plays a role in calcium-induced calcium-release during chick heart development. T-type current plays a significant role in the calcium-induced calcium-release process in younger embryos due to the greater magnitude of the current at earlier developmental stages. 3. More than one isoform of the T-type calcium channel is present in developing chick myocardium. The multiple isoforms will function concomitantly to provide sufficient T-type calcium current for proper development. 4. The expression of the T-type calcium channel in ventricle decreases with development. There is a concomitant decrease in T-type Ca2* current stimulation of CICR. SPECIFIC AIMS 1. To determine the contribution of T-type calcium current to the calcium transient during development in chick ventricular myocytes. The approach is to use a fluorescent calcium indicator to measure the transients from myocytes at embryonic day (ED) 5, EDI 1 andED15. 2. To determine the contribution of T-type calcium current to calcium-induced calciumrelease during chick heart development. The approach is to use pharmacological agents to quantify the contribution to the Ca3* transient from T-type Ca3* current stimulated CICR. 3. To determine which isoforms of the T-type calcium channel are likely to be present in chick myocardium. The approach is to use PCR methods to identify any T-type channel isoform mRNA expressed in chick ventricle. 4. To determine the level of expression of T-type calcium channel isoforms during the development of chick ventricle. The approach is to use molecular quantitation methods to examine the expression pattern of T-type channel isoforms in chick ventricle during development. |
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