How to update fields in a table type valueset?

Hi

I need to create an integrator using which the valueset creation process is going to be automatized. I have found the api using which an independent valueset can be modified (values can be added to it).

But  I am unable to find an api using which an existing table type valueset can be modified (I need to modify ID, value, meaning, where clause). Is there any api to do this ?

Thanks.