4. FUTURE PERSPECTIVES.
Future research should aim to compare quantitatively the expression of the discussed peptides and receptors, both in relation to sex and age. Preliminary expression studies suggest that (i) CGRP and CT are the most expressed of the studied peptides, (ii) that CGRP receptor and CTR are the most frequently expressed receptor types and (iii) that AM2, AMY1 and AMY3receptors occur in rat TG, but are mainly localized to the SGCs. The demonstration of the specific ligands and receptor sites in TG neurons highlights the importance of CGRP and the CGRP receptor as viable contributors in primary headache disorders. Future investigations of the expression of the CGRP-family of peptides near the node of Ranvier is warranted. Understanding the location and distribution is important in deciding on how to identify future targets for anti-migraine medications and this will facilitate future drug development and ultimately enrich the therapeutic options for the patients.