Calls out for past demands (8)
I believe the answer is:
exclaims
'calls out' is the definition.
('exclaim' can be a synonym of 'call out')
'past demands' is the wordplay.
'past' becomes 'ex' (similar in meaning).
'demands' becomes 'claims' (claiming is a kind of demanding).
'ex'+'claims'='EXCLAIMS'
'for' is the link.
(Other definitions for exclaims that I've seen before include "Cries out in climaxes" , "Suddenly cries out" , "Cries out from pain or surprise" .)