|MadSci Network: Biochemistry|
I'm sorry that I've taken so long to answer your question Ashley, but it is so specific that I've had to do quite a bit of research to come up with some sort of answer for you. I don't think that I can help you in terms of ligand-receptor interactions, but I have come up with some candidate drug-like compounds that are found in celery, and to which you and your mother might have extra sensitivity.
To start, here is a list of all the chemicals found in celery. Many of these have a broad range of activities, but I've narrowed things down into three categories of compounds.
First we have the coumarin family of compounds; these are aromatic molecules that exhibit a variety of cytotoxic effects when exposed to UV light. From the list, we have Bergapten, Coumarin, Isopimpinellin (dimethyl psoralen), Psoralen, Scopoletin, and Xanthotoxin (8-methoxy Psoralen). All of these (and more) are present in celery. However, I wonder how often you eat celery while being exposed to a source of UV light.
Second, we have the bio-flavinoid family of compounds. These have enjoyed recent status as general cure-alls, being widely touted for their vasodilatory, anti-carcinogenic, anti-inflammatory, anti-microbial, immune stimulating, and anti-allergic effects. But they also have cytotoxic properties (among their numerous other properties). Both the compounds Apigenin and Rutin are bio-flavinoids found in celery.
Third, and I think most likely, is the compound Eugenol. This is the active ingredient in Clove Oil, and is used in temporary dental fillings to deaden the nerve pain of a cavity. The numbness that you experience from celery might be due to the numbing effects of Eugenol on your tounge.
As you can see from the list; there are many other compounds that have drug-like effects (e.g. Nicotine and Myristicin). Researching these might lead you to other candidate compounds.
I hope this helps some.
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