Beschrijving

Testo 400 – Royal Pharmaceuticals (400 mg/ml Testosterone Blend)

Category: Injectable Testosterone Blend (Research Only)
Brand: Koninklijke Farmaceutische Producten
Concentration: 400 mg/ml total testosterone esters
Packing: 10 × 1 ml ampoules
Origin: United Kingdom
Price: €59
Use Notice: Laboratory research and analytical applications only – not for human or veterinary administration.

🧪 What Is Testo 400?

Testo 400 is a high-strength oil-based testosterone blend containing 400 mg/ml of testosterone ester prodrugs. After intramuscular injection, esterases gradually convert these esters into free testosterone, making it a standard reference compound in androgen-receptor studies, pharmacokinetics, and doping-analysis research.
Because the exact ester composition is not stated on the label, the material is catalogued as “Testosterone blend, 400 mg/ml (mixed esters)”.

🔬 Mechanism of Action (Testosterone Esters)

Prodrug activation

Each ester (e.g., enanthate, cypionate, decanoate, etc.) becomes active testosterone only after enzymatic cleavage. The oil depot slows release, producing a multi-day to multi-week exposure curve depending on ester length.

Androgen receptor signalling

• Released testosterone diffuses into cells
• In some tissues converts to DHT
• Binds to intracellular androgen receptors
• Hormone–receptor complex regulates androgen-responsive genes

This results in increased protein synthesis, nitrogen retention, erythropoiesis, and modulation of androgen-dependent metabolic pathways.

📚 Research Context & Applications

• Analytical chemistry: calibration standards for LC-MS/MS, GC-MS and HPLC testosterone detection
• Release-profile modelling: ester hydrolysis rate and depot-release kinetics
• Androgen-receptor studies: receptor binding, transcriptional response, cross-talk with other hormonal pathways
• Anti-doping research: development of detection windows for exogenous testosterone

These applications refer strictly to laboratory and analytical use.

📈 Expected Research-Level Observations

• Rise in free and esterified testosterone concentrations over extended periods
• Measurement of testosterone → DHT and testosterone → estradiol metabolic pathways
• Changes in androgen-responsive gene expression in cellular models
• Modulation of nitrogen balance and erythropoietic markers in experimental models

⚠️ Safety Profile & Potential Adverse Effects (Testosterone Class)

Endocrine & Reproductive

• Suppression of LH/FSH
• Reduced endogenous testosterone production
• Decreased spermatogenesis and testicular atrophy

Cardiovascular & Haematological

• Increased hematocrit / polycythaemia
• Adverse lipid shifts (↓HDL, ↑LDL)
• Possible elevation in blood pressure

Androgenic Effects

• Acne, oily skin, male-pattern hair loss
• Virilisation in female exposure

Psychological & Neurologic

• Mood change, irritability, aggression

Hepatic Considerations

• Low intrinsic hepatotoxicity compared with 17-α-alkylated orals
• Liver enzymes may still fluctuate under certain conditions

These points derive from known properties of testosterone esters and are provided for scientific completeness.

🛑 Compliance & Legal Status

• Testosterone and its esters are controlled substances or prescription-only medications in most jurisdictions.
• Listed under WADA S1 “Anabolic Agents” — prohibited at all times.
• Product is supplied strictly for laboratory, analytical, and research use only.

📊 Technical Data Table

For laboratory and research use only. Not for human or veterinary administration.