Hindawi Publishing Corporation International Journal of Peptides Volume 2015, Article ID 828759, 7 pages http://dx.doi.org/10.1155/2015/828759 Research Article Correlation between Saliva and Plasma Levels of Endothelin Isoforms ET-1, ET-2, and ET-3 Roma Gurusankar,1 Prem Kumarathasan,2 Anusha Saravanamuthu,2 Errol M. Thomson,1 and Renaud Vincent1 1 Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada K1A 0K9 2Analytical Biochemistry and Proteomics Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada K1A 0K9 Correspondence should be addressed to Renaud Vincent;
[email protected] Received 17 January 2015; Revised 17 March 2015; Accepted 18 March 2015 Academic Editor: Kazuhiro Takahashi Copyright © 2015 Roma Gurusankar et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Although saliva endothelins are emerging as valuable noninvasive cardiovascular biomarkers, reports on the relationship between isoforms in saliva and plasma remain scarce. We measured endothelins in concurrent saliva and plasma samples (=30males; age 18–63) by HPLC-fluorescence. Results revealed statistically significant positive correlations among all isoforms between saliva and plasma: big endothelin-1 (BET-1, 0.55 ± 0.27 versus 3.35 ± 1.28 pmol/mL; = 0.38, = 0.041), endothelin-1 (ET-1, 0.52 ± 0.21 versus 3.45 ± 1.28 pmol/mL; = 0.53, = 0.003), endothelin-2 (ET-2, 0.21 ± 0.07 versus 1.63 ± 0.66 pmol/mL; = 0.51, = 0.004), and endothelin-3 (ET-3, 0.39 ± 0.19 versus 2.32 ± 1.44 pmol/mL; = 0.75, < 0.001).