Hypertonicity-induced cation channels

Autor: E Endl, F ter Veld, Tongju Li, Maryna Bondarava, Frank Wehner, H R Nürnberger
Rok vydání: 2006
Předmět:
Zdroj: Acta Physiologica. 187:21-25
ISSN: 1748-1716
1748-1708
DOI: 10.1111/j.1748-1716.2006.01561.x
Popis: Whenever studied in a quantitative fashion, hypertonicity-induced cation channels (HICCs) are found to be the main mediators of regulatory volume increase. In most instances, these channels are either inhibited by amiloride (but insensitive to Gd3+ and flufenamate) or they are efficiently blocked by Gd3+ and flufenamate (but insensitive to amiloride). Of note, however, from two preparations so far a mixed type of pharmacology has also been reported. Whereas the ion selectivity of amiloride-sensitive HICCs has not been studied in much detail yet, amiloride-insensitive channels are either equally permeable to Na+, K+, Cs+ and Li+ but impermeable to N-methyl-D-glucamine (NMDG+) or they exhibit a permeability to Li+ and NMDG+ that amounts to some 50% when compared with that of Na+. Also in this respect, however, some peculiarities do exist. Concerning the actual molecular correlate, evidence was reported that HICCs may be related to the (amiloride-sensitive) epithelial Na+ channel and/or to transient receptor potential channels. Recent findings suggest that HICCs may contribute to cell proliferation, just as the K+ channels that are employed in regulatory volume decrease are mediators of the opposing process, i.e. apoptosis.
Databáze: OpenAIRE
Externí odkaz: