Aging
Definition
The irreversible loss of one alkyl group from the phosphorylated AChE-organophosphate complex, after which oximes can no longer reactivate the enzyme. Aging half-times range from minutes (soman) to many hours (most agricultural OPs).
- Mechanism
- Irreversible loss of an alkyl group from phosphorylated AChE
- Consequence
- Oximes can no longer reactivate the enzyme
- Fastest agent
- Soman, minutes
- Slowest agents
- Most agricultural organophosphates, many hours
Common questions
Why does aging time matter for treating organophosphate poisoning?+
Oxime antidotes such as pralidoxime only work before the enzyme-inhibitor complex ages, so a fast-aging agent narrows the treatment window dramatically compared with a slow-aging pesticide, where oximes may remain effective for many hours after exposure.
Does aging affect all organophosphates at the same rate?+
No, the aging half-time varies enormously by compound, from minutes for military nerve agents like soman to many hours for common agricultural organophosphates, which is a major reason clinical urgency differs so much between exposure types.
Related terms
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