title: Inhibition of 11beta-hydroxysteroid dehydrogenase in guinea pig kidney by three bioflavonoids and their interactions with gossypol.
abstract: OBJECTIVE
  To study the effects of some bioflavonoids on the gossypol-induced hypokalemia.
  
  
  METHODS
  The 11beta-hydroxysteroid dehydrogenase (11beta-OHSD) protein was prepared from guinea pig kidney. The activity of 11beta-OHSD with NAD as the coenzyme was measured by HPLC. The drug interaction was analysed by isobolographic method.
  
  
  RESULTS
  The 11beta-OHSD can be inhibited by some bioflavonoids. The IC50 (95 % confidence limits) values were: quercetin 164 (79 - 341) micromol/L, morin 913 (385 - 2173) micromol/L, and naringenin 2193 (1114 - 4315) micromol/L. When the 11beta-OHSD was treated with quercetin, tangeretin, morin, naringenin plus gossypol, the combination index (CI) values were 0.92, 0.85, 0.98, and 1.01 respectively.
  
  
  CONCLUSIONS
  The interaction of some bioflavonoids with gossypol might be one of the factors for gossypol-induced hypokalemia.
authors.affiliation: Department of Biochemical Pharmacology, Family Planning Research Institute, Zhejiang Academy of Medical Sciences, Hangzhou 310013, China.
authors.forename: Mao-Shan
authors.initials: MS
authors.lastname: Wang
authors.forename: Hong
authors.initials: H
authors.lastname: Shi
authors.forename: Ke-Shen
authors.initials: KS
authors.lastname: Wang
authors.forename: Marcus M
authors.initials: MM
authors.lastname: Reidenberg
mesh_terms: D043205:11-beta-Hydroxysteroid Dehydrogenase Type 1; D000818:Animals; D003864:Depression, Chemical; D004357:Drug Synergism; D004791:Enzyme Inhibitors; D047309:Flavones; D005419:Flavonoids / Q000494:pharmacology*; D006072:Gossypol / Q000009:adverse effects / Q000494:pharmacology*; D006168:Guinea Pigs; D006913:Hydroxysteroid Dehydrogenases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D007008:Hypokalemia / Q000139:chemically induced; D008297:Male; D009243:NAD / Q000378:metabolism; D011794:Quercetin / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D047309:Flavones; D005419:Flavonoids; D009243:NAD; C008548:morin; D011794:Quercetin; D006913:Hydroxysteroid Dehydrogenases; D043205:11-beta-Hydroxysteroid Dehydrogenase Type 1; C059006:tangeretin; D006072:Gossypol