| 毒性 |
A small basic protein (Mr57000). It contains 62
amino acids in a single chain, cross-linked by four disulfide
bonds. The toxin comprises 10% of the venom by weight. It is
a neurotoxin that is secreted by glands of the cobra snake and
injected into its prey via immobile, grooved fangs. Cobratoxin
may be radiolabeled and used as a specific radioligand in binding
studies performed on acetylcholine receptors. Cobratoxin is absorbed from the subcutaneous tissues and is distributed
throughout the body. After intoxication, high concentrations
are found at the motor endplates of neuromuscular junctions,
where it irreversibly binds to acetylcholine receptors. The primary
action is similar to that of curare, but the binding process
is slower. |
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