Journal
CELLULAR AND MOLECULAR NEUROBIOLOGY
Volume 28, Issue 8, Pages 1119-1128Publisher
SPRINGER/PLENUM PUBLISHERS
DOI: 10.1007/s10571-008-9288-8
Keywords
Anthopleura sp; Recombinant neurotoxins; Cerebral cortical neurons; Voltage-gated Na plus channels; Inactivation
Categories
Funding
- Guangdong Science-Tech Program [2001331004202516]
- Ministry of Science and Technology of China [2007AA091401]
- Science Foundation of Life Sciences School
- Sun Yat-sen University
Ask authors/readers for more resources
We have investigated the action of the recombinant neurotoxins, named Hk7a and Hk2a, whose amino acid sequences differ only in two positions, isolated from the sea anemone Anthopleura sp., on neuronal sodium currents using the whole-cell voltage-clamp techniques. The rat cerebral cortical neurons in primary culture were used for this study. In our experiments, these cells all express tetrodotoxin-sensitive (TTX-S) sodium currents. Under the voltage-clamp condition, application of Hk7a and Hk2a reduced the sodium channel current amplitude and shifted the voltage dependence of activation to more positive potential; while Hk7a produced no significant effect on the voltage at which 50% of the channels were inactivated, Hk2a caused profound hyperpolarizing shift of the voltage-dependent inactivation. Also, both Hk7a and Hk2a increased the time course of recovery from inactivation. In kinetic studies, whereas application of Hk2a slows the time to peak of voltage-gated sodium channel, the time course of fast and slow inactivating component, no significant effect was observed in Hk7a. These results suggested that the difference of key amino acid between Hk7a and Hk2a might contribute to their different action; therefore, they could be used as pharmacological tool to study the structure and function of voltage-gated sodium channel.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available