Loop Through Combobox Objects To Add Items?

method of looping through objects to make changes.

I have 12 comboboxes on a userform which I have set to dropdown list and want to populate during the userform initialization. Each combobox is called "pt*" where * is a number from 1 - 12. I have currently set up my code with 12 lines, one for each combobox to apply the same dropdown list to each of the 12 boxes.

ie
Code:
pt1.rowsource = ptsource
(where ptsource contains a range reference on the worksheet)

I'm interested to learn how to improve my code to loop through 1-12 and apply the rowsource to each combobox.

I did search through some past questions but could only come up with a method which seemed to step through every combobox on a worksheet rather than userform and in my case, I have two other comboboxes on the userform which I do not want to add this rowsource to, only the "pt*" named comboboxes.