A 17beta-hydroxy steroid that is testosterone in which the 4,5 double bond has been reduced to a single bond with alpha-configuration at position 5.
Identification
17beta-hydroxy-5alpha-androstan-3-one
17beta-hydroxy-5alpha-androstan-3-one
17beta-Hydroxy-5alpha-androstan-3-one
17beta-hydroxy-5alpha-androstan-3-one
17beta-hydroxyandrostan-3-one
17beta-Hydroxyandrostan-3-one
17beta-Hydroxyandrostan-3-one
4,5alpha-dihydrotestosterone
5alpha-DHT
5alpha-dihydrotestosterone
5alpha-Dihydrotestosterone
androstanolona
Androstanolone
androstanolone
androstanolone
androstanolonum
DHT
Dihydrotestosteron
DIHYDROTESTOSTERONE
dihydrotestosterone
Stanolone
Species
mus musculus
NCBI:txid10090 19425150
daphnia magna
NCBI:txid35525 Changes in the Metabolic Elimination Profile of Testosterone Following Exposure of the Crustacean Daphnia magna to TributyltinGerald A. LeBlanc and James B. McLachlanEcotoxicology and Environmental Safety 45, 296-303 (2000)
homo sapiens
NCBI:txid9606 10.1038/nbt.2488
NCBI:txid9606 10625505
NCBI:txid9606 16585475
Europe PubMed Central results
Mnemonic effects of testosterone and its 5alpha-reduced metabolites in the conditioned fear and inhibitory avoidance tasks.
Author: Edinger KL, Lee B, Frye CA.
Abstract: Experiments were conducted to examine whether performance in hippocampally-mediated learning tasks is influenced by testosterone (T) and/or its 5alpha-reduced metabolites, dihydrotestosterone (DHT) and 3alpha-androstanediol (3alpha-diol). Performance in the conditioned fear and inhibitory avoidance tasks were examined in intact and gonadectomized (GDX), androgen-replaced rats. In Experiment 1, the behavior of intact and GDX rats in the conditioned fear paradigm were compared. GDX rats spent more time freezing, an index of increased learning, in the context, hippocampally-mediated task, but not in the cued, amygdala-mediated task. In Experiment 2, GDX rats were administered T, DHT, 3alpha-diol, estrogen (E2), or vehicle 1 mg/kg sc after training in the conditioned fear paradigm. T-, 3alpha-diol-, or E2-, compared with vehicle-administered rats, spent significantly more time freezing in the contextual, but not the cued, condition. In Experiment 3, intact compared with GDX rats had significantly longer crossover latencies, indicating better performance, in the inhibitory avoidance task. In Experiment 4, T, DHT, 3alpha-diol, or vehicle 1 mg/kg sc was administered to GDX rats immediately following training in the inhibitory avoidance task. Rats administered T, DHT, or 3alpha-diol had significantly longer crossover latencies compared with vehicle controls. In Experiment 5, androgen levels in the hippocampus were elevated 1 h following administration, when androgen exposure is essential for consolidation. These data indicate that androgens effects to enhance learning may be mediated in part by actions of 5alpha-reduced metabolites in the hippocampus.
Effects of testosterone metabolites on copulation, medial preoptic dopamine, and NOS-immunoreactivity in castrated male rats.
Author: Putnam SK, Sato S, Riolo JV, Hull EM.
Abstract: The medial preoptic area (MPOA) is an important integrative site for male sexual behavior. Dopamine (DA) is released in the MPOA of male rats shortly before and during copulation. In a previous study, we identified 17beta-estradiol (E(2)) as the metabolite of testosterone (T) that maintains MPOA basal extracellular DA levels. However, the presence of dihydrotestosterone (DHT), an androgenic metabolite of T, is required for the female-induced increase in MPOA DA observed during copulation. Recently, we reported that assays of MPOA tissue DA content showed that castrates actually had more stored DA than did gonadally intact males. Therefore, the reduction in extracellular levels in castrates was not due to decreased availability of DA; most likely it was due to decreased release. Furthermore, T upregulates neuronal nitric oxide synthase (nNOS) in the MPOA. NO has been implicated in the regulation of DA release in the MPOA. It is not known, however, which metabolite(s) of T regulate(s) tissue stores of DA and/or nNOS in the MPOA of male rats. The present experiments were designed to test the following: (1) whether E(2), DHT, or the combination of the two influences MPOA DA tissue levels, an indication of stored DA, in male rat castrates; and (2) whether E(2), DHT, or the combination of the two influences NOS-ir in the MPOA of castrated male rats. The results indicate that E(2) up-regulates nNOS-ir in the MPOA and maintains tissue content of DA at levels similar to those in T-treated rats. DHT did not influence nNOS-ir, while attenuating the effect of castration on tissue DA content.
Safety aspects of androgen treatment with 5alpha-dihydrotestosterone.
Author: Sakhri S, Gooren LJ.
Abstract: 5alpha-Dihydrotestosterone (DHT), the most powerful naturally occurring androgen, is commercially available since 1982 as a gel. In view of its considerably higher biopotency (three to six times) than of testosterone, side effects, particularly on the main target organ of androgens, the prostate, are anticipated. In fact, DHT appears to be a prostate-sparing androgen for two reasons. Unlike testosterone, it does not undergo any further amplification in biopotency through 5alpha reduction in the prostate. Secondly, it is likely to lead to less aromatisation of testosterone to oestradiol in the prostate, thus reducing local oestradiol concentrations. Oestrogens have been implicated in the aetiology of benign prostate hyperplasia and prostate cancer. However, aromatisation of testosterone has appeared to be essential for the maintenance of bone mineral density. Administration of DHT reduces circulating oestradiol levels, but the levels remain above the levels critical for the antiresorptive effect of oestrogens on bone. Effects of DHT on erythropoiesis and on lipids are very similar to those of testosterone. Safety concerns regarding androgen treatment with DHT are similar to those of treatment with testosterone, while the effects of DHT on the prostate are likely to be less biopotent.