Aim: Calcitonin gene-related peptide (CGRP) is a predominant neurotransmitter in sensory nerves.It has been reported that the expression of CGRP in lung was decreased in PF patients evoked by crystalline silica and crocidolite and CGRP significantly inhibited vascular remodeling in hypoxia-induced PAH.Therefore, in the present study, we tested whether the inhibitory regulation of CGRP on lung fibroblasts proliferation and pulmonary fibrosis was through inhibition of eukaryotic initiation factor 3a (eIF3a) expression.