RT Journal Article
SR Electronic
T1 PST2238: A New Antihypertensive Compound That Antagonizes the Long-Term Pressor Effect of Ouabain
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 83
OP 94
VO 285
IS 1
A1 Ferrari, P.
A1 Torielli, L.
A1 Ferrandi, M.
A1 Padoani, G.
A1 Duzzi, L.
A1 Florio, M.
A1 Conti, F.
A1 Melloni, P.
A1 Vesci, L.
A1 Corsico, N.
A1 Bianchi, G.
YR 1998
UL http://jpet.aspetjournals.org/content/285/1/83.abstract
AB The inhibition of the long-term pressor effect of ouabain may be useful for the therapy of essential hypertension. Here, for the first time, a selective inhibitor of the ouabain pressor effect is described.In vitro, 17β-(3-furyl)-5β-androstane-3β, 14β, 17α-triol (PST 2238) displaced ouabain from its binding sites on purified sodium, potassium ATPase enzyme (Na-K ATPase) (IC50 1.7 × 10−6 M) without interacting with other receptors involved in blood pressure regulation or hormonal control. In cultured renal cells, incubation with ouabain (10−10 to 10−8 M) for 5 days stimulated the Na-K pump at Vmax, whereas PST 2238 showed the same effect at micromolar concentration. The ouabain-dependent increase in the Na-K pump rate was abolished by PST 2238 at concentrations from 10−14 to 10−9 M. In rats made hypertensive by chronic infusion of 50 μg/kg/day of ouabain, PST 2238 given p.o at very low doses (0.1–1 μg/kg/day for 4 weeks) abolished the increase in blood pressure and renal Na-K ATPase activity caused by ouabain. PST 2238 did not affect either blood pressure or renal Na-K ATPase activity in normotensive rats. In conclusion, PST 2238 is a very potent compound that normalizes both blood pressure and alterations in the Na-K pump caused by ouabain. Thus it represents the prototype of a new class of antihypertensive drugs that could be effective in forms of hypertension sustained by the concomitant increase of endogenous ouabain levels and alterations in the Na-K pump. The American Society for Pharmacology and Experimental Therapeutics