| In Vivo: |
PST 2238, given orally at very low doses (1 and 10 microg/kg for 5-6 weeks), reduced the development of hypertension in MHS rats and normalized the increased renal Na,K-ATPase activity and mRNA levels, whereas it did not affect either blood pressure or Na,K-ATPase in Milan-normotensive (MNS) rats [2]. |
| In Vitro: |
PST 2238 displaced [3H]ouabain from the dog kidney Na+,K+-ATPase receptor (IC50 ) 1.5X 10-6M), was devoid of cardiac inotropic activity in isolated guinea pig atria, and showed no affinity up to 10-4 M with general (R1, R2, a1, a2, A1, A2, M1, M2, H1, H2, 5-HT1, 5-HT2, Ca2+ channels, TXA2/PGH2, PAF, GABAA, GABAB, DA-NE-5-HT uptake, glutammate,glycine, benzodiazepine) and hormonal (estrogenic, progestinic, androgenic, mineralcorticoid) receptors [1]. At molecular level, in the kidney, Rostafuroxin antagonizes EO triggering of the Src-epidermal growth factor receptor (EGFr)-dependent signaling pathway leading to renal Na+-K+ pump, and ERK tyrosine phosphorylation and activation [3]. |
| References: |
[1]. Quadri L, et al. 17 beta-(3-furyl)-5 beta-androstane-3 beta, 14 beta, 17 alpha-triol (PST 2238). A very potent antihypertensive agent with a novel mechanism of action. J Med Chem. 1997 May 23;40(11):1561-4.
[2]. Ferrari P, et al. PST 2238: A new antihypertensive compound that modulates Na,K-ATPase in genetic hypertension. J Pharmacol Exp Ther. 1999 Mar;288(3):1074-83.
[3]. Ferrari P, et al. Rostafuroxin: an ouabain antagonist that corrects renal and vascular Na+-K+- ATPase alterations in ouabain and adducin-dependent hypertension. Am J Physiol Regul Integr Comp Physiol. 2006 Mar;290(3):R529-35. |
