CALCA and migraine disorder: It is also possible that CTR without RAMPs has a role to play in the TG because administration of calcitonin and activation of CTR alone has previously been shown to be anti-nociceptive, including in migraine sufferers (Micieli et al., 1988; Ustdal et al., 1989; Humble, 2011; Ito et al., 2012).