You have not specified which technology you are using, but by writing "...open a link...", I presume it is about html/css/js.
I can think of three types of highlighting.
Adding an .active:
You could add a class, which somehow highlights the drilldown, by using a correlating color, changing font weight, adding shadow or/and transformations. This all can be done by css.
Adding an .inactive:
Reduce the visibility, alpha and color of the inactive sections.
By using icons you could show the user that a certain entity is open. Examples could be an open and closed folders, triangle arrows or plus/minus etc. Font Awesome is a nice example to accomplish that.
In case of "...open a link...":
If for example an anachor is already set, instead of already display the drilldown on load, you could set a timeout, scroll to the section, open it and let it flicker once. This can be easily done by jQuery.
The position of the drilldown should be inside of the table rows. Also do not overdo it. Sometimes less is more.
Bootstrap has some buildin functions to accomplish your thoughts. Maybe you should take a look.