＞98%

Store at -20℃ for one year（Powder）；Store at 2-4℃ for two weeks；Store at -20℃ for six months after dissolution.

甲磺suan酚妥拉明

白色或类白色结晶性粉末

DMSO : 37.8 mg/mL (100 mM)

water : 37.8 mg/mL (100 mM)

α-adrenergic receptor

Phentolamine mesylate displaces binding of the selective alpha 1 receptor antagonists HEAT and prazosin and the alpha 2 receptor antagonists rauwolscine and RX 821002 with relatively high affinity in corpus cavernosum membranes. Phentolamine mesylate causes concentration dependent relaxation in erectile tissue strips pre-contracted with adrenergic agonists penylephrine, norepinephrine, oxymetazoline and UK 14,304, as well as with non-adrenergic contractile agents Endothelin and KCl. Phentolamine mesylate induces relaxation of corpus cavernosum erectile tissue by direct antagonism of alpha 1 and 2 adrenergic receptors and by indirect functional antagonism via a non-adrenergic, endothelium-mediated mechanism suggesting nitric oxide synthase activation. Phentolamine, an alpha-adrenergic antagonist, blocks the vasoconstriction associated with the epinephrine used in dental anesthetic formulations, thus enhancing the systemic absorption of the local anesthetic from the injection site.

Phentolamine is a reversible competitive alpha-adrenergic antagonist with similar affinities for alphal and alpha2 receptors. Phentolamine mesylate causes vasodilatation and thus hypotension by decreasing peripheral vascular resistance. Phentolamine mesylate (30 and 100 nM) dose-dependently enhances electrical field stimulation-induced relaxation of the rabbit corpus cavernosum. Phentolamine relaxes rabbit corpus cavernosum independent of alpha-adrenergic receptor blockade. Phentolamine mesylate relaxes nonadrenergic noncholinergic neurons of the rabbit corpus cavernosum by activating NO synthase and is independent of alpha-adrenergic receptor blockade.