Expression of calcitonin gene-related peptide-1 receptor mRNA in human tooth pulp and trigeminal ganglion

Numerous nerve fibres containing calcitonin gene-related peptide (CGRP) were found by immunocytochemistry in human molar pulp. These nerves were often seen around small blood vessels and as free endings without vascular contact. In the trigeminal ganglion a large number of CGRP-immunoreactive nerve-cell bodies, mostly of small to medium size, was encountered. Reverse transcriptase-polymerase chain reaction, using specific sense and antisense primers, detected mRNA expression of the human CGRP1 receptor in the pulp tissue and the trigeminal ganglion. Thus, both CGRP-containing nerve fibres and CGRP1 receptor mRNA are present in human tooth pulp, where they may be involved in the regulation of vascular tone and other local reactions to injury.