Nejvíce citovaný článek - PubMed ID 11081638
Transient receptor potential cation channels subfamily V member 4 (TRPV4) are non-selective cation channels expressed in different cell types of the central nervous system. These channels can be activated by diverse physical and chemical stimuli, including heat and mechanical stress. In astrocytes, they are involved in the modulation of neuronal excitability, control of blood flow, and brain edema formation. All these processes are significantly impaired in cerebral ischemia due to insufficient blood supply to the tissue, resulting in energy depletion, ionic disbalance, and excitotoxicity. The polymodal cation channel TRPV4, which mediates Ca2+ influx into the cell because of activation by various stimuli, is one of the potential therapeutic targets in the treatment of cerebral ischemia. However, its expression and function vary significantly between brain cell types, and therefore, the effect of its modulation in healthy tissue and pathology needs to be carefully studied and evaluated. In this review, we provide a summary of available information on TRPV4 channels and their expression in healthy and injured neural cells, with a particular focus on their role in ischemic brain injury.
- Klíčová slova
- Ca2+ signaling, TRPV4, astrocytes, glia, ischemia,
- MeSH
- astrocyty * metabolismus MeSH
- centrální nervový systém metabolismus MeSH
- cerebrální infarkt MeSH
- ischemie mozku * metabolismus MeSH
- kationtové kanály TRPV * metabolismus MeSH
- lidé MeSH
- mozek metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- kationtové kanály TRPV * MeSH
- TRPV4 protein, human MeSH Prohlížeč
The vanilloid receptor [transient receptor potential (TRP)V1, also known as VR1] is a member of the TRP channel family. These receptors share a significant sequence homology, a similar predicted structure with six transmembrane-spanning domains (S1-S6), a pore-forming region between S5 and S6, and the cytoplasmically oriented C- and N-terminal regions. Although structural/functional studies have identified some of the key amino acids influencing the gating of the TRPV1 ion channel, the possible contributions of terminal regions to vanilloid receptor function remain elusive. In the present study, C-terminal truncations of rat TRPV1 have been constructed to characterize the contribution of the cytoplasmic C-terminal region to TRPV1 function and to delineate the minimum amount of C tail necessary to form a functional channel. The truncation of 31 residues was sufficient to induce changes in functional properties of TRPV1 channel. More pronounced effects of C-terminal truncation were seen in mutants lacking the final 72 aa. These changes were characterized by a decline of capsaicin-, pH-, and heat-sensitivity; progressive reduction of the activation thermal threshold (from 41.5 to 28.6 degrees C); and slowing of the activation rate of heat-evoked membrane currents (Q10 from 25.6 to 4.7). The voltage-induced currents of the truncated mutants exhibited a slower onset, markedly reduced outward rectification, and significantly smaller peak tail current amplitudes. Truncation of the entire TRPV1 C-terminal domain (155 residues) resulted in a nonfunctional channel. These results indicate that the cytoplasmic COOH-terminal domain strongly influences the TRPV1 channel activity, and that the distal half of this structural domain confers specific thermal sensitivity.
- MeSH
- buněčné linie MeSH
- elektrická vodivost MeSH
- imunohistochemie MeSH
- kapsaicin farmakologie MeSH
- koncentrace vodíkových iontů MeSH
- krysa rodu Rattus MeSH
- lidé MeSH
- metoda terčíkového zámku MeSH
- molekulární modely MeSH
- molekulární sekvence - údaje MeSH
- mutace MeSH
- proteinkinasa C metabolismus MeSH
- protony MeSH
- receptory léků chemie genetika fyziologie MeSH
- sekvence aminokyselin MeSH
- sekvenční delece MeSH
- sekvenční seřazení MeSH
- serin genetika MeSH
- terciární struktura proteinů MeSH
- vysoká teplota MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- kapsaicin MeSH
- proteinkinasa C MeSH
- protony MeSH
- receptory léků MeSH
- serin MeSH