converting string from list to variable

[alo]

I have a list {x1,x2,x3...}->z when x1,x2.. may differ in each input.
in the function I have to use those x1,x2 as variables :
x1=5
x2=6
...
I tried 5->#z[1] (argument must be a string error)or
5->#"z[1]" (indirection string is not a valid variable name error)

Thanks

[mellamokb]

Try 5->z(1)

~ mellamokb