TY - JOUR
T1 - Endothelium-independent vasodilation effect of di- and tri-peptides in thoracic aorta of Sprague-Dawley rats
AU - Tanaka, Mitsuru
AU - Tokuyasu, Mai
AU - Matsui, Toshiro
AU - Matsumoto, Kiyoshi
N1 - Funding Information:
The authors thank S. Watanabe, Faculty of Agriculture, Kyushu University, for his technical support. This study was in part supported by a grand for JSPS Research Fellowships for Young Scientists to MT and in part by a grand-in-aid for the Ministry of Education, Science, Sports and Culture of Japan (No. 19208012) to TM.
PY - 2008/4/9
Y1 - 2008/4/9
N2 - The goal of this study was to elucidate the structure-activity relationship for vasodilating peptides and their underlying mechanism. In this study, we synthesized 62 di- and tri-peptides having aromatic amino acid residues (Tyr, Trp and Phe). Among them, only 4 peptides (HW, WH, WL and WV) evoked an apparent vasodilating effect in 50 mM KCl-contracted aortic rings in the descending order of WH>HW>WL>WV; WH showed the vasodilating activity with an EC50 of 3.4 mM. Within our experimental results, it seems likely that Trp residue at the N-terminal would play a role in eliciting vasodilating effect. No appearance of vasodilating effect for stereoisomers of WH with D-configuration revealed that the vessel would recognize the l-configuration of WH. The presence of angiotensin I-converting enzyme (ACE) inhibitor (50 nM enalaprilat) did not affect the WH-induced vasodilating effect, though WH showed a slight ACE inhibitory activity (IC50: 93 μM). The effect was also observed in the endothelium-denuded aortic rings. In contrast, WH provoked a significant displacement to the right in the vasodilating curve in the presence of 30 nM verapamil, while no shift was observed in the presence of 2.5 nM nifedipine. These results indicate that WH, a vasodilating di-peptide, would exert a vasodilation via the suppression of Ca2+ influx into KCl-induced depolarized aortic rings. The present study also suggests that the binding site of WH to the Ca2+ channel may be competitive to that of phenylalkylamine-type voltage-gated L-type Ca2+ channel blocker.
AB - The goal of this study was to elucidate the structure-activity relationship for vasodilating peptides and their underlying mechanism. In this study, we synthesized 62 di- and tri-peptides having aromatic amino acid residues (Tyr, Trp and Phe). Among them, only 4 peptides (HW, WH, WL and WV) evoked an apparent vasodilating effect in 50 mM KCl-contracted aortic rings in the descending order of WH>HW>WL>WV; WH showed the vasodilating activity with an EC50 of 3.4 mM. Within our experimental results, it seems likely that Trp residue at the N-terminal would play a role in eliciting vasodilating effect. No appearance of vasodilating effect for stereoisomers of WH with D-configuration revealed that the vessel would recognize the l-configuration of WH. The presence of angiotensin I-converting enzyme (ACE) inhibitor (50 nM enalaprilat) did not affect the WH-induced vasodilating effect, though WH showed a slight ACE inhibitory activity (IC50: 93 μM). The effect was also observed in the endothelium-denuded aortic rings. In contrast, WH provoked a significant displacement to the right in the vasodilating curve in the presence of 30 nM verapamil, while no shift was observed in the presence of 2.5 nM nifedipine. These results indicate that WH, a vasodilating di-peptide, would exert a vasodilation via the suppression of Ca2+ influx into KCl-induced depolarized aortic rings. The present study also suggests that the binding site of WH to the Ca2+ channel may be competitive to that of phenylalkylamine-type voltage-gated L-type Ca2+ channel blocker.
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U2 - 10.1016/j.lfs.2008.02.001
DO - 10.1016/j.lfs.2008.02.001
M3 - Article
C2 - 18329669
AN - SCOPUS:41149164074
VL - 82
SP - 869
EP - 875
JO - Life Sciences
JF - Life Sciences
SN - 0024-3205
IS - 15-16
ER -