tokens: The evoked increases in dural blood flow were also abolished by topical pre - administration of atropine ( 1 mm ) and [ Lys1 , Pro2 , 5 , Arg3 , 4 , Tyr6 ] - VIP ( 0 . 1 mm ) , a vasoactive intestinal polypeptide ( VIP ) antagonist , onto the exposed dura mater .