The mystery of celery and its effects on your cat

Those of you that follow Fox Valley Cat Clinic on facbook may already know about my unscientific study.  If not, this is your chance to be a part of my research. :)

I am interested in the effects of celery leaves on your cat compared to catnip.  Sounds crazy?  I have a good client that recently told me a story about his cat's suprising response to fresh celery leaves.  This cat treats celery leaves as if they were catnip by acting silly, rolling, rubbing and  vocalizing.
Having never heard of this response before, I thought I would experiment on my menagerie as well as ask others to report their results of similar celery leaf experimentation at home.
The results?  So far, no other cats are interested in celery leaves.
Please feel free to test this out at home and report back to me.  Perhaps our test group is not large enough...?
Dr. Maureen Flatley