OBJECTIVETo search for specific protein makers and target proteins for intervention with Yimusake Tablets (YT) in the penile tissue of rats with ED induced by compound cold stress and explore the molecular mechanisms underlying the development and progression of ED.METHODSEighty adult male rats were screened and divided into three groups, normal control (n = 10), ED model control (n = 15) and YT intervention (n = 15). The model of compound cold stress-induced ED was established in the latter two groups, and meanwhile the animals in the YT intervention group were treated with oral YT for 2 weeks. After that, proteins were extracted from the penile tissues of the rats for screening and identification by iTRAQ labeling combined with LC-MS-MS proteomics, and the IPA bioinformatics software was used for analysis of differentially expressed proteins.RESULTSA total of 48 differentially expressed proteins were identified from the penile tissue of the ED model controls, of which 18 were associated with endothelial function, 5 with smooth muscle activity and 4 with inflammation, involving the biological processes of glucose metabolism and alcohol catabolism and the signaling pathways of glucose metabolism, calcium and RXR activation. In comparison, 29 differentially expressed proteins were identified from the rats in the YT intervention group, of which 5 were associated with endothelial function, 1 with smooth muscle activity and 4 with inflammation, involving the biological processes of glucose metabolism, vasodilation and acute-phase response and the signaling pathways glucose metabolism, RXR activation and acute-phase response. Seven ED-associated candidate biomarkers were obtained from the differentially expressed proteins in the ED model control and YT intervention group, including Collagen alpha-1(III) chain(COL3α1), Collagen alpha-1(I) chain(COL1α1), Collagen alpha-2(I) chain(COL1α2), Glyceraldehyde-3-phosphate dehydrogenase(GAPDH), T-kininogen 1(MAP1),Biglycan(BGN), and Myosin-11(MYH11).CONCLUSIONSChanges of vascular endothelial and smooth muscle functions in the penile tissue are likely to be the key mechanisms underlying the development and progression of compound stress-induced ED, which is also associated with inflammation as well as the interaction of the identified differentially expressed proteins and their participation in the relevant signaling pathways. The 7 proteins obtained can be used as the markers of compound stress-induced ED in the rat penile tissue, of which MAP1, GAPDH, BGN and MYH11 may serve as target proteins for YT intervention.