Channel Blocker Function
Channel blockers are signal transduction reagents able to prevent the opening of an ion channel, acting as antagonists. Different type of molecules, such as cations, anions, amino acids, peptides and other chemicals can block channels.
Ion channels are protein complexes, often comprised out of many proteins, that form pores inside a membrane. These channels can selectively permit the passage of ions through the membrane in which they are situated. Often channels can switch between an open and a closed state by different stimuli. Since ions carry electrical charges, ion channels are important for the regulation of the membrane potential, which is necessary for processes such as neurotransmission, muscle contraction and T-cell activation. Whether the particular ions can pass through the channel or not depends on different factors like:
• Ion concentration inside or outside of the membrane
• Condition of the channel (open / closed)
• Presence of agonists or antagonists
Channel Blocker Mechanisms and Applications
Channel blockers can act specifically on one channel, or on a range of different channels. The blockage is mediated by the binding of the channel blocker to a portion of the channel. The different mechanisms vary between channels and blockers, but all blockers produce an alteration in the electrochemical gradient of the cell membrane.
Prominent examples of channel blockers are calcium (Ca) channel blockers, which are used as antihypertensive drugs or various toxins like Tetrodotoxin (TTX) that act through the blockage of ion channels. Other blockers are specific to potassium (K) and sodium (Na) channels.
Channel blockers are used for various experiments like:
• Evaluation of signal transduction pathways
• Production or suppression of physiological responses
• Treatment of diseases
• Ion channel detection