Obeyed (9)
(Another definition for conformed that I've seen is " toed the party line".)
'obeyed' is the definition.
(heeding is a kind of obeying)
This is all the clue.
(Other definitions for heeded that I've seen before include "Took notice of" , "Took note" , "Paid attention to, say warning" , "Listened, minded" , "Respected" .)