I think it is considered hazardous material under DOT regulations. There are exceptions for small quantities, such as perfumes which are also hazardous. Pam is an aerosol flammable (cooking oil) so it may not pass the muster. Check specifically with your airline and any transferring airlines.

You might want to consider buying a pumpable aerosol sprayer designed to be reloaded with cooking oil. I use this instead of Pam. Biggest problem is they tend to plug and you don't get as uniform a spray as Pam but it seems to work as well. More environmentally friendly too. Travel with it empty.