CALCA and infection: CGRP plays a role in the pathophysiology of cutaneous leishmaniasis, and this role is suggested to be the reason behind the failure of susceptible BALB/c mice (express less CGRP + ve fibres compared to resistant C57BL/6 mice) to mount a proper immune response against Leishmania compared to C57BL/6 mice during the first week of infection [73].