Fig. 1.

Bath application of metrifonate significantly decreased the accommodation and the postburst AHP in CA1 neurons from aging subjects. An example of the effect of metrifonate on accommodation is illustrated in A–C(same neuron). A depicts a typical response elicited during the 800 msec depolarizing pulse obtained in baseline measures.B illustrates a typical increase in number of action potentials elicited during the accommodation pulse after the perfusate has been changed to 200 μm metrifonate. Cdepicts a typical decrease in the number of action potentials elicited after the perfusate has been changed to a combination of 200 μm metrifonate and 1 μm atropine, indicating that the metrifonate effect is muscarinic. An example of the AHP decrement observed after the perfusate has been changed to a 100 μm metrifonate in CA1 neurons from aging subjects is illustrated in D (scales for B andC are the same as that of A).