title: Effects of Etomidate on the Steroidogenesis of Rat Immature Leydig Cells.
abstract: BACKGROUND
  Etomidate is a rapid hypnotic intravenous anesthetic agent. The major side effect of etomidate is the reduced plasma concentration of corticosteroids, leading to the abnormal reaction of adrenals. Cortisol and testosterone biosynthesis has similar biosynthetic pathway, and shares several common steroidogenic enzymes, such as P450 side chain cleavage enzyme (CYP11A1) and 3β-hydroxysteroid dehydrogenase 1 (HSD3B1). The effect of etomidate on Leydig cell steroidogenesis during the cell maturation process is not well established.
  
  
  METHODS
  Immature Leydig cells isolated from 35 day-old rats were cultured with 30 μM etomidate for 3 hours in combination with LH, 8Br-cAMP, 25R-OH-cholesterol, pregnenolone, progesterone, androstenedione, testosterone and dihydrotestosterone, respectively. The concentrations of 5α-androstanediol and testosterone in the media were measured by radioimmunoassay. Leydig cells were cultured with various concentrations of etomidate (0.3-30 μM) for 3 hours, and total RNAs were extracted. Q-PCR was used to measure the mRNA levels of following genes: Lhcgr, Scarb1, Star, Cyp11a1, Hsd3b1, Cyp17a1, Hsd17b3, Srd5a1, and Akr1c14. The testis mitochondria and microsomes from 35-day-old rat testes were prepared and used to detect the direct action of etomidate on CYP11A1 and HSD3B1 activity.
  
  
  CONCLUSIONS
  In intact Leydig cells, 30 μM etomidate significantly inhibited androgen synthesis. Further studies showed that etomidate also inhibited the LH- stimulated androgen production. On purified testicular mitochondria and ER fractions, etomidate competitively inhibited both CYP11A1 and HSD3B1 activities, with the half maximal inhibitory concentration (IC50) values of 12.62 and 2.75 μM, respectively. In addition, etomidate inhibited steroidogenesis-related gene expression. At about 0.3 μM, etomidate significantly inhibited the expression of Akr1C14. At the higher concentration (30 μM), it also reduced the expression levels of Cyp11a1, Hsd17b3 and Srd5a1. In conclusion, etomidate directly inhibits the activities of CYP11A1 and HSD3B1, and the expression levels of Cyp11a1 and Hsd17b3, leading to the lower production of androgen by Leydig cells.
authors.affiliation: Department of Anesthiology, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People's Republic of China.
authors.forename: Hua-Cheng
authors.initials: HC
authors.lastname: Liu
authors.affiliation: Department of Anesthiology, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People's Republic of China.
authors.forename: Danyan
authors.initials: D
authors.lastname: Zhu
authors.affiliation: Department of Anesthiology, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People's Republic of China.
authors.forename: Chan
authors.initials: C
authors.lastname: Wang
authors.affiliation: School of Pharmacy, Wenzhou Medical University, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, People's Republic of China.
authors.forename: Hongguo
authors.initials: H
authors.lastname: Guan
authors.affiliation: Department of Anesthiology, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People's Republic of China.
authors.forename: Senlin
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Anesthiology, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People's Republic of China.
authors.forename: Cong
authors.initials: C
authors.lastname: Hu
authors.affiliation: Department of Anesthiology, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People's Republic of China.
authors.forename: Zhichuan
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Anesthiology, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People's Republic of China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Department of Anesthiology, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People's Republic of China.
authors.forename: Han
authors.initials: H
authors.lastname: Lin
authors.affiliation: Department of Anesthiology, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People's Republic of China.
authors.forename: Qing-Quan
authors.initials: QQ
authors.lastname: Lian
authors.affiliation: Department of Anesthiology, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, People's Republic of China.
authors.forename: Ren-Shan
authors.initials: RS
authors.lastname: Ge
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases / Q000096:biosynthesis / Q000235:genetics; D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase / Q000096:biosynthesis / Q000235:genetics; D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000728:Androgens / Q000096:biosynthesis*; D018686:Anesthetics, Intravenous / Q000494:pharmacology / Q000633:toxicity*; D000818:Animals; D002478:Cells, Cultured; D002786:Cholesterol Side-Chain Cleavage Enzyme / Q000096:biosynthesis / Q000235:genetics; D003470:Culture Media / Q000494:pharmacology; D003600:Cytosol / Q000737:chemistry; D004960:Estradiol Dehydrogenases / Q000096:biosynthesis / Q000235:genetics; D005045:Etomidate / Q000494:pharmacology / Q000633:toxicity*; D005786:Gene Expression Regulation / Q000187:drug effects; D012739:Gonadal Steroid Hormones / Q000494:pharmacology; D007985:Leydig Cells / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D008297:Male; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics; D008861:Microsomes / Q000737:chemistry; D008928:Mitochondria / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D013737:Testis / Q000166:cytology / Q000254:growth & development
chemical_list: D000728:Androgens; D018686:Anesthetics, Intravenous; D003470:Culture Media; D012739:Gonadal Steroid Hormones; D008565:Membrane Proteins; D015124:8-Bromo Cyclic Adenosine Monophosphate; D015067:17-Hydroxysteroid Dehydrogenases; C476565:17beta-hydroxysteroid dehydrogenase type 3; D004960:Estradiol Dehydrogenases; D002786:Cholesterol Side-Chain Cleavage Enzyme; D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase; C548472:Srd5a1 protein, rat; D005045:Etomidate