title: Combining growth hormone-releasing hormone antagonist with luteinizing hormone-releasing hormone antagonist greatly augments benign prostatic hyperplasia shrinkage.
abstract: OBJECTIVE
  Benign prostatic hyperplasia often affects aging men. Antagonists of the neuropeptide growth hormone-releasing hormone reduced prostate weight in an androgen induced benign prostatic hyperplasia model in rats. Luteinizing hormone-releasing hormone antagonists also produce marked, protracted improvement in lower urinary tract symptoms, reduced prostate volume and an increased urinary peak flow rate in men with benign prostatic hyperplasia. We investigated the influence of a combination of antagonists of growth hormone-releasing hormone and luteinizing hormone-releasing hormone on animal models of benign prostatic hyperplasia.
  
  
  METHODS
  We evaluated the effects of the growth hormone-releasing hormone antagonist JMR-132, given at a dose of 40 μg daily, the luteinizing hormone-releasing hormone antagonist cetrorelix, given at a dose of 0.625 mg/kg, and their combination on testosterone induced benign prostatic hyperplasia in adult male Wistar rats in vivo. Prostate tissue was examined biochemically and histologically. Serum levels of growth hormone, luteinizing hormone, insulin-like growth factor-1, dihydrotestosterone and prostate specific antigen were determined.
  
  
  RESULTS
  Marked shrinkage of the rat prostate (30.3%) occurred in response to the combination of growth hormone-releasing hormone and luteinizing hormone-releasing hormone antagonists (p<0.01). The combination strongly decreased prostatic prostate specific antigen, 6-transmembrane epithelial antigen of the prostate, interleukin-1β, nuclear factor-κβ and cyclooxygenase-2, and decreased serum prostate specific antigen.
  
  
  CONCLUSIONS
  A combination of growth hormone-releasing hormone antagonist with luteinizing hormone-releasing hormone antagonist potentiated a reduction in prostate weight in an experimental benign prostatic hyperplasia model. Results suggest that this shrinkage in prostate volume was induced by the direct inhibitory effects of growth hormone-releasing hormone and luteinizing hormone-releasing hormone antagonists exerted through their respective prostatic receptors. These findings suggest that growth hormone-releasing hormone antagonists and/or their combination with luteinizing hormone-releasing hormone antagonists should be considered for further development as therapy for benign prostatic hyperplasia.
authors.affiliation: Veterans Affairs Medical Center and South Florida Veterans Affairs Foundation for Research and Education, Miami, Florida 33125, USA. FRick@med.miami.edu
authors.forename: Ferenc G
authors.initials: FG
authors.lastname: Rick
authors.forename: Luca
authors.initials: L
authors.lastname: Szalontay
authors.forename: Andrew V
authors.initials: AV
authors.lastname: Schally
authors.forename: Norman L
authors.initials: NL
authors.lastname: Block
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Nadji
authors.forename: Karoly
authors.initials: K
authors.lastname: Szepeshazi
authors.forename: Irving
authors.initials: I
authors.lastname: Vidaurre
authors.forename: Marta
authors.initials: M
authors.lastname: Zarandi
authors.forename: Magdolna
authors.initials: M
authors.lastname: Kovacs
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Rekasi
mesh_terms: D000818:Animals; D004359:Drug Therapy, Combination; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors* / Q000627:therapeutic use; D013007:Growth Hormone-Releasing Hormone / Q000037:antagonists & inhibitors*; D008297:Male; D009929:Organ Size / Q000187:drug effects; D011470:Prostatic Hyperplasia / Q000188:drug therapy* / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D017337:Sermorelin / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: C534070:GHRH(1-29)NH2, PhAcTyr(1)-Arg(2)-P(H)e(4-CL)(6)-Ala(8)-Tyr(Me)(10)-His(11)-Abu(15)-His(20)-Nle(27)-Arg(28)-HLCr(29)-; D007987:Gonadotropin-Releasing Hormone; D017337:Sermorelin; D013007:Growth Hormone-Releasing Hormone; C062876:cetrorelix