Simultaneous determination of testosterone, dihydrotestosterone and 5 alpha-androstan-3 alpha,-17 beta-diol by isotopic dilution mass spectrometry in plasma and prostatic tissue of patients affected by benign prostatic hyperplasia. Effects of 3-month treatment with a GnRH analog.
This article reports an isotope dilution mass spectrometric method for the simultaneous measurement of testosterone (T), dihydrotestosterone (DHT), and 5 alpha-androstan-3 alpha, 17 beta-diol (3 alpha-diol) in human plasma and prostatic tissue. After addition of tri-deuterated steroids as internal standards to prostatic tissue homogenates or plasma samples, extraction was performed with diethylether. The extracts were purified by two chromatographic steps (Sep-Pak C 18 cartridge and Sephadex LH-20) and injected into a gas chromatograph coupled with a mass spectrometer after derivatization with heptafluorobutyric acid. This method was highly specific and showed good precision, accuracy, reproducibility and sensitivity. T, DHT, and 3 alpha-diol were measured in human plasma and in prostatic tissue of seven patients with benign prostatic hyperplasia (BPH) treated for 3 months with a long acting GnRH analog before surgery. Plasma levels of T, DHT, and 3 alpha-diol were reduced by GnRH analog treatment to castrate levels. The tissue concentrations of the same steroids, compared with those obtained from 19 untreated patients, showed a mean reduction of about 90% for DHT and 3 alpha-diol, and about 75% for T. These results suggest that about 90% of prostatic DHT and 3 alpha-diol depend on testicular activity because they are dramatically reduced after pharmacologic castration.
Salerno
R
R
Department of Clinical Physiopathology, University of Florence, Italy.
Moneti
G
G
Forti
G
G
Magini
A
A
Natali
A
A
Saltutti
C
C
Di Cello
V
V
Costantini
A
A
Serio
M
M
D015113:Androstane-3,17-diol / Q000097:blood*; D000732:Androstanols / Q000097:blood*; D002064:Buserelin / Q000627:therapeutic use*; D013196:Dihydrotestosterone / Q000097:blood*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008297:Male; D008722:Methods; D011467:Prostate / Q000032:analysis*; D011470:Prostatic Hyperplasia / Q000188:drug therapy / Q000473:pathology*; D013739:Testosterone / Q000097:blood*
D000732:Androstanols; D013196:Dihydrotestosterone; D015113:Androstane-3,17-diol; D013739:Testosterone; D002064:Buserelin