I doubt it. You certainly can't do it from the Airport App.
You can check/see the MAC addresses by clicking on the icon/image of the APE in the AirPort app. Then you should see an info window with 'edit' in the bottom right corner of the window. You should see the name of the APE at the top of the window. Hold down the option key while clicking the name.
The MAC address is attached to specific hardware modules inside. The only time I have seen changing the MAC address is on virtual devices, such as changing it on the NIC in Parallels.
It's also worth mentioning that the APE has three MAC addresses, 1 ethernet, 1 2.4Ghz and 1 5Ghz.