6] M) were administered 10 min before veratrine (1 X [10.
4] M) were added 20 min and 10 min, respectively, before administering veratrine (1 x [10.
Paeoniflorin (Nacalai Tesque Japan), veratrine hydrochloride (Sigma, USA), verapamil hydrochloride (Sigma USA), ethylene glycol-bis([beta]-aminoethyl ether) N,N,N',N'-tetraacetic acid (EGTA)(Sigma USA), naloxone (Sigma USA), ryanodine (RBI USA), norepinephrine (RBI USA) and potassium chloride (Merck USA) were dissolved in Krebs' Ringer solution.
2] M) had no effect on isolated rat and mouse vas deferens (data are not shown), but veratrine (1 x [10.
As Tables 1 and 2 show, the phasic contractions induced by veratrine were concentration-dependent.