MARC 主機 00000nam  2200325   4500 
001    AAI3117970 
005    20051017073436.5 
008    051017s2004                        eng d 
020    0496653946 
035    (UnM)AAI3117970 
040    UnM|cUnM 
100 1  Blair, Nathaniel Tyler 
245 10 Contributions of voltage-gated sodium, calcium and 
       potassium currents to the excitability of nociceptive 
       sensory neurons 
300    229 p 
500    Source: Dissertation Abstracts International, Volume: 65-
       01, Section: B, page: 0093 
500    Adviser: Bruce P. Bean 
502    Thesis (Ph.D.)--Harvard University, 2004 
520    In this thesis I have studied how the voltage-gated 
       conductances expressed in nociceptors control various 
       aspects of action potential generation during stimuli of 
       varying duration and frequency. In Chapter 2 I present 
       experiments using the action potential clamp method to 
       measure the TTX-sensitive sodium, TTX-resistant sodium and
       calcium currents flowing during nociceptor action 
       potentials, and focus on how inactivation shapes the 
       contributions of TTX-sensitive and TTX-resistant sodium 
       channels. The TTX-resistant sodium current contributes the
       majority of charge transferred during the action potential,
       and due to its slow and incomplete inactivation, 
       contributes a significant fraction of the inward charge 
       during the action potential shoulder.  Chapter 3 describes
       the role of TTX-resistant sodium current slow inactivation
       in the adaptation of firing in nociceptive sensory 
       neurons. Although TTX-resistant sodium channels recover 
       from fast inactivation quite quickly, their rapid entry to
       slow inactivation prevents nociceptors from firing 
       continuously throughout a depolarizing stimulus. Lastly, 
       in Chapter 4 I describe the role of Kv3 and large 
       conductance calcium-activated potassium channels in 
       nociceptor action potential repolarization and in action 
       potential broadening that occurs during repetitive 
       stimulation. These studies will help in understanding the 
       control of nociceptor excitability, and how changes in 
       conductances might contribute to hyperalgesic states 
590    School code: 0084 
590    DDC 
650  4 Biology, Neuroscience 
650  4 Chemistry, Biochemistry 
690    0317 
690    0487 
710 20 Harvard University 
773 0  |tDissertation Abstracts International|g65-01B 
856 40 |u