Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Carbenoxolone sodium, CS, a liquorice derivative associated with hypertension and sodium retention, has been demonstrated to inhibit 11 beta-hydroxysteroid dehydrogenase, an enzyme that metabolizes cortisol and corticosterone to their respective inactive 11-dehydro products (cortisone and 11-dehydrocorticosterone). It has been proposed that the increased bioavailability of unmetabolized corticosterone and cortisol following 11 beta-OHSD inhibition allows these steroids to act on renal mineralocorticoid receptors to elicit the mineralocorticoid action. Here we describe how CS amplifies the antinatriuretic activity of aldosterone and deoxycorticosterone; the latter steroid is of particular importance in that it does not possess a hydroxyl group at the C-11 position in the steroid ring, indicating that another mechanism(s) in addition to 11 beta-OHSD inhibition is responsible for the amplification of the action of deoxycorticosterone.
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PMID:The 11 beta-OHSD inhibitor, carbenoxolone, enhances Na retention by aldosterone and 11-deoxycorticosterone. 231 75

In humans, diminished 11 beta-hydroxysteroid dehydrogenase (11 beta-OHSD) enzyme activity has been associated with sodium retention and hypertension. These studies show that the toad bladder, another target tissue epithelium displaying steroid-induced sodium transport, possesses the enzyme 11 beta-OHSD. The toad urinary bladder rapidly transformed corticosterone (3 x 10(-8) M) (50% by 10 min and 90% by 180 min) with 11-dehydrocorticosterone being the major metabolite. The 11-dehydrocorticosterone produced reached an apparent plateau when the tissue incubations were repeated with higher concentrations of corticosterone (10(-7) and 10(-6) M). Carbenoxolone sodium (2.5 x 10(-5) M), a water soluble derivative of glycyrrhetinic acid, markedly inhibited the metabolism of corticosterone (3 x 10(-8) M) to 11-dehydrocorticosterone similar to previous observations in the mammalian kidney. Carbenoxolone sodium (2.5 x 10(-5) M) did not significantly affect short-circuit current (SCC) in toad bladders when added to either the serosal or mucosal bath. However, when carbenoxolone sodium was added to the mucosal bath and 60 min later corticosterone 10(-6) M was placed in the serosal bath, bladders generated a SCC 2.07 +/- 0.17 (mean +/- SE) times above base line at 360 min compared with 1.48 +/- 0.11 in bladders exposed to corticosterone alone (P less than 0.02). In parallel experiments, carbenoxolone sodium in the mucosal bath enhanced the rise in SCC induced by cortisol 10(-6) M; 1.66 +/- 0.16 times above base line at 360 min compared with 1.07 +/- 0.14 with cortisol alone (P less than 0.02). We conclude that the toad bladder contains 11 beta-OHSD and inhibition of this enzyme with carbenoxolone sodium is associated with amplification of glucocorticoid-induced transepithelial sodium transport in this tissue. However, since the quantity of 11-dehydro-product produced appears to be limited, other factors in addition to inhibition of 11 beta-OHSD may play a role in this amplification of sodium transport.
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PMID:Effect of carbenoxolone on glucocorticoid metabolism and Na transport in toad bladder. 250 91