The antagonistic properties of YM471, a potent nonpeptide vasopressin (AVP) V1A and V2 receptor antagonist, were characterized using human coronary artery smooth muscle cells (CASMC). YM471 potently inhibited specific binding of 3H-AVP to V1A receptors on human CASMC, exhibiting a Ki value of 0.49 nM. Furthermore, YM471 inhibited the AVP-induced increase in intracellular free Ca2+ concentration with an IC50 value of 1.42 nM, but exerted no agonistic activity on CASMC. Additionally, while AVP concentration-dependently induced hyperplasia and hypertrophy in CASMC, YM471 prevented these AVP-induced growth effects, exhibiting IC50 values of 0.93 and 2.64 nM, respectively. These results indicate that YM471 has high affinity for V1A receptors on, and high potency in inhibiting AVP-induced physiologic responses of, human CASMC.
|Number of pages||8|
|Publication status||Published - 2002 Oct 1|
- Coronary artery
- Smooth muscle cells
- V receptor
ASJC Scopus subject areas
- Cellular and Molecular Neuroscience