Na+/K+ channel

Antidepressants Noradrenaline/5-HT transporters Na+, K+ channels l Noradrenaline/ 5-HT reuptake l Na+ currents t K+ currents l Excitability of peripheral and central neurons Cardiac arrhythmia, myocardial infarction, sedation, nausea, dry mouth, constipation, dizziness, sleep disturbance, blurred vision... 

HT3 Depolarisation Ligand-gated Na+/K+ channel 2-methyl 5-HT Ondansetron Postsynaptic and... 

For the internalisation of metals, many examples exist for which transport may be coupled to an energy-dependent process, of which only a few are described here. For example, the well-studied (e.g. [276]) Na+/K+ channel transports 3Na+ out and 2K+ in for each ATP molecule that is hydrolysed [242]. Mg2+ influx (but likely not efflux) is highly regulated in eukaryotes [277]. ATPases have been implicated in certain cases of Fe [278] or Zn [90] uptake by phytoplankton. Finally, although Cd internalisation by a polychaete appeared to be energy independent, accumulation was increased rather than decreased in the presence of ATPase inhibitors, suggesting that the efflux system might depend upon ATP synthesis [279]. 

Cation-TT interactions play a crucial role in molecular recognition. For example, Na /K cation interactions with aromatic rings of some amino acids are implicated in the biological functions of specific enzymes and in the selectivity of Na" /K channels. " The same factors are responsible of the relative stability of the charge-solvated vs. zwitterionic structure of amino acids. " ... 

Nicotinic Nn Postganglionic neurons, some presynaptic cholinergic terminals Opening of Na+,K+ channels, depolarization... 

ACh (muscarinic) receptors, AChE G < membrane delimited proteins G < activated K+ channel Ca++, Na+, K+ Channels... 

A potent aaivator of the cAMP, cyclic nucleotide-gated (CNG) Na+/K+ channel in olfactory cells is NO (nitric oxide), which is many times more potent than cAMP. However, NO is present only in developing olfactory neurons, where it seems to react directly with cysteine SH-groups in the P-subunit of the channel. It was speculated, therefore, that NO might be a channel activator early in development or in regenerating olfactory neurons (see ref. 91). 

The acetylcholine diffuses across the gap between the nerve terminal and the muscle membrane, (the neuromuscular cleft) and binds to receptors on the muscle surface. This results in the opening of Na /K channels and Na flows down its concentration gradient into the muscle. This ion flux causes a localised depolarisation, termed an "endplate potential", in the muscle. This nerve-evoked electrical disturbance can be measured using a microelectrode inserted into the muscle cell at the neuromuscular junction region and compared to a reference electrode. When the amplitude of this depolarisation reaches a threshold level a regenerative electrical depolarisation, known as an "action potential" is triggered in the muscle. This action potential is transmitted into the muscle cell where it triggers contraction of the muscle fibre. At the mammalian neuromuscular junction there is normally a 1 1 relationship between nerve action potentials and muscle action potentials. 

Na, K channels Aconitine and related diterpene alkaloids veratridine, zygadenine, and related steroidal alkaloids ajmaline, vincamine, ervatamine, mitragynine, and other indole alkaloids dicentrine and other aporphine alkaloids gonyautoxin paspalitrem and related indoles phalloidine, quinidine, and related quinoline alkaloids sparteine and related quinolizidine alkaloids saxitoxin strychnine tetrodotoxin... 

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