AChRs exhibit three different half-lives, depending on the state of innervation.

TA muscles of anaesthetized mice were injected with 125I-BGT on day zero and then 125I emission from injected hindlimbs was measured over 25 days. Regressions from data sets normalized to day 2 after pulse labeling were calculated using two-exponential terms and t1/2 values of 1.1 days (fast compartment), 8.1 days (intermediate compartment) and 13.1 days (slow compartment). The table shows compartment sizes, rate constants, half-lives, and mean receptor lifetimes, all ± SD (n-values: control n = 10, acutely denervated n = 5, long-term denervated n = 4).