Nandrolone decanoate (Deca-Durabolin) is a 19-nortestosterone ester with a high anabolic-to-androgenic ratio (125:37 vs testosterone’s 100:100). The 19-nor scaffold means it cannot be converted by 5α-reductase to a more androgenic DHT analog — it converts instead to the weaker dihydronandrolone — producing significantly less androgenic activity in tissues (prostate, skin, scalp) than equivalent doses of testosterone. The decanoate ester extends half-life to ~15 days, making it a true depot injection. Research applications include muscle wasting (sarcopenia, cachexia, HIV wasting), bone density, anaemia, and the differential AR activation profile in androgen-sensitive vs androgen-resistant tissues.
Following decanoate ester hydrolysis, nandrolone activates the androgen receptor with high affinity — but with tissue-specific differences vs testosterone due to 5α-reductase metabolism:
Muscle: Full AR agonism → MPS, IGF-1 upregulation, satellite cell activation. High anabolic effect
Prostate/skin/scalp: 5α-reductase converts nandrolone → dihydronandrolone (weak AR agonist) — minimal androgenic effect vs testosterone → DHT in same tissues
Progestogenic: Nandrolone activates progesterone receptor — relevant to HPG axis suppression (LH/FSH) and gynecomastia research
Bone: AR activation in osteoblasts → bone mineral density; also via IGF-1 upregulation
Erythropoiesis: EPO upregulation in kidney — haematocrit increase
Why nandrolone is used to study tissue-selective androgen signalling
The contrast between nandrolone and testosterone in 5α-reductase-expressing vs non-expressing tissues is the basis for studying tissue-selective AR activation. In muscle (low 5α-reductase), nandrolone and testosterone are comparably anabolic. In prostate and skin (high 5α-reductase), nandrolone produces much less androgenic stimulation because dihydronandrolone is a weak AR agonist while DHT is highly potent. This makes nandrolone the reference compound for tissue-selective androgen receptor modulator (SARM) research design.
Key Research Studies & Clinical Data
Key nandrolone research
Study
Population
Key finding
Johansen et al. 1999
HIV-wasting patients, nandrolone vs placebo 16 weeks
Lean body mass +3.6 kg nandrolone vs −0.5 kg placebo; quality of life improvement
Schols et al. 1995
COPD cachexia, nandrolone + pulmonary rehab
Lean mass gain, 6-min walk improvement vs exercise alone
Menke et al. 2017 review
Renal failure anaemia, nandrolone historical data
Haematocrit improvement before erythropoietin era; now reference for EPO-comparison research
Research Protocols — Nandrolone Decanoate
Protocol 1: Muscle wasting/cachexia model (castrated rat)
Orchidectomy + 2 weeks recovery → nandrolone decanoate 10 mg/kg IM once weekly × 8 weeks vs testosterone vs vehicle. Gastrocnemius mass, grip strength, MPS (puromycin), AR expression (IHC), satellite cells.
Protocol 2: Anabolic:androgenic dissection
Nandrolone vs testosterone vs DHT in orchidectomised rat. Levator ani (anabolic marker) vs seminal vesicle weight (androgenic marker). Maps tissue-selective AR activation.
Protocol 3: Bone density
Nandrolone decanoate 5–15 mg/kg IM weekly × 12 weeks in ovariectomised rats. Femur and lumbar spine BMD (DXA/µCT), trabecular architecture, osteocalcin, bone ALP.
Protocol 4: HPG + progesterone receptor
Nandrolone vs testosterone in intact male rats. LH/FSH suppression (time course), PR expression in pituitary, testicular weight and spermatogenesis at 8 weeks.
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Frequently Asked Questions
What is nandrolone decanoate?
Nandrolone decanoate is a 19-nortestosterone anabolic-androgenic steroid with a decanoate ester (15-day half-life). Its 5α-reductase metabolism to a weak androgen makes it more tissue-selective than testosterone — high anabolic activity in muscle, low androgenic activity in prostate and skin.
Why does nandrolone have a high anabolic ratio?
The anabolic:androgenic ratio of 125:37 (vs testosterone 100:100) arises because nandrolone is not converted to a potent androgen by 5α-reductase in androgenic tissues. 5α-reductase converts testosterone → DHT (strong androgen); it converts nandrolone → dihydronandrolone (weak androgen). So the androgenic side effects in prostate/skin are diminished while muscle anabolic effects are preserved.
What is nandrolone used for in research?
Research applications include muscle wasting/cachexia models, sarcopenia, bone density in hypogonadal animals, erythropoiesis, tissue-selective androgen receptor biology, and HPG axis suppression studies. It is also used as the reference compound for SARM research due to its tissue selectivity profile.
What formats does QSC supply nandrolone in?
QSC supplies nandrolone decanoate at 200 mg/mL injectable, in vial kits. Ships from QSC domestic warehouses in USA, EU, UK, Canada, and Australia.
What is the difference between nandrolone and testosterone for research?
Testosterone converts to DHT (highly androgenic) via 5α-reductase in prostate, skin, and scalp. Nandrolone converts to dihydronandrolone (weakly androgenic) in the same tissues. Both have similar AR affinity in muscle. This differential metabolism makes nandrolone the tool for studying anabolic effects without full androgenic receptor activation in 5α-reductase-expressing tissues.
Research Use Only: All QSC compounds are sold strictly for laboratory research purposes. Not for human use. Not approved by the FDA or equivalent regulatory bodies for human administration. All purchases confirm research intent and compliance with applicable local regulations.
