Background:

Phentolamine mesylate is a competitive, reversible α-adrenoceptor antagonist with an IC50 between 5 and 30 nM.

参考文献:
[1]. Giussani, D.A., et al., Alpha 1- and alpha 2-adrenoreceptor actions of phentolamine and prazosin on breathing movements in fetal sheep in utero. J Physiol, 1995. 486 ( Pt 1): p. 249-55.
[2]. Saeed, M., et al., Alpha-adrenoceptor blockade by phentolamine causes beta-adrenergic vasodilation by increased catecholamine release due to presynaptic alpha-blockade. J Cardiovasc Pharmacol, 1982. 4(1): p. 44-52.