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CYP isoenzymes
++ = mitochondrial | |||||
| CYP11 2 subfamilies, 3 genes
(steroid biosynthesis) | |||||
| Isoenzyme | Substrates | Inducer | Inhibitor | Alleles | Effects (alleles, interactions) |
| CYP11A1++ | "cholesterol side chain cleavage enzyme" (converts cholesterol to pregnenolone) | branched phosphatidylcholines | ? | ? | the first and rate-limiting enzyme in all steroid biosynthesis! (deficiency: congenital adrenal hyperplasia) |
| CYP11B1++ | (11 beta hydroxylase : makes cortisol from 11-deoxycortisol)
(adrenal fasciculata/reticularis; ? also vascular endothelium! ) | ACTH | ? | ? | (deficiency: CAH, hypertension) |
| CYP11B2++ | (aldosterone synthase: hydroxylates corticosterone)
(adrenal glomerulosa alone; ? also vascular smooth muscle!! ) ) | angiotensin II; high potassium, low sodium | ? | ? | (may be important in angiogenesis!) The -344C allele in the promoter region greatly increases the risk of nonfatal MI in those with smoking and dyslipidaemia [Circulation 1999 Nov 30;100(22):2213-8] |
| Last update 2000-1-22 | Author jo@anaesthetist.com |