We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Effects of eupatilin on the contractility of corpus cavernosal smooth muscle through nitric oxide-independent pathways.
- Authors
Choo, S. H.; Lee, S. W.; Chae, M. R.; Kang, S. J.; Sung, H. H.; Han, D. H.; Chun, J. N.; Park, J. K.; Kim, C. Y.; Kim, H. K.; So, I.
- Abstract
Eupatilin (5,7-dihydroxy-3,4,6-trimethoxyflavone) is one of the main compounds present in Artemisia species. Eupatilin has both antioxidative and anti-inflammatory properties and a relaxation effect on vascular contraction regardless of endothelial function. We evaluated the relaxant effects of eupatilin on the corpus cavernosum ( CC) of rabbits and the underlying mechanisms of its activity in human corpus cavernosum smooth muscle ( CCSM) cells. Isolated rabbit CC strips were mounted in an organ bath system. A conventional whole-cell patch clamp technique was used to measure activation of calcium-sensitive K+-channel currents in human CCSM cells. The relaxation effect of eupatilin was evaluated by cumulative addition (10−5 m ~ 3 × 10−4 m) to CC strips precontracted with 10−5 m phenylephrine. Western blotting analysis was performed to measure myosin phosphatase targeting subunit 1 ( MYPT1) and protein kinase C-potentiated inhibitory protein for heterotrimeric myosin light chain phosphatase of 17- kDa ( CPI-17) expression and to evaluate the effect of eupatilin on the RhoA/Rho-kinase pathway. Eupatilin effectively relaxed the phenylephrine-induced tone in the rabbit CC strips in a concentration-dependent manner with an estimated EC50 value of 1.2 ± 1.6 × 10−4 m ( n = 8, p < 0.05). Iberiotoxin and tetraethylammonium significantly reduced the relaxation effect ( n = 8, p < 0.001 and p = 0.003, respectively). Removal of the endothelium or the presence of L- NAME or indomethacin did not affect the relaxation effect of eupatilin. In CCSM cells, the extracellular application of eupatilin 10−4 m significantly increased the outward currents, and the eupatilin-stimulated currents were significantly attenuated by treatment with 10−7 m iberiotoxin ( n = 13, p < 0.05). Eupatilin reduced the phosphorylation level of MYPT1 at Thr853 of MLCP and CPI-17 at Thr38. Eupatilin-induced relaxation of the CCSM cells via NO-independent pathways. The relaxation effects of eupatilin on CCSM cells were partially due to activation of BKCa channels and inhibition of RhoA/Rho-kinase.
- Subjects
ARTEMISIA; SYMPATRIC speciation; WESTERN immunoblotting; PROTEIN kinases; PHOSPHOTRANSFERASES
- Publication
Andrology, 2017, Vol 5, Issue 5, p1016
- ISSN
2047-2919
- Publication type
Article
- DOI
10.1111/andr.12397