Androgen Receptor

As all testosterone esters, testosterone propionate is rapidly hydrolysed into free testosterone in plasma. Testosterone is metabolized to 17-keto steroids through two different pathways. The major active metabolites are estradiol and dihydrotestosterone (DHT).Testosterone propionate is rapidly hydrolysed into testosterone. Testosterone is metabolized to 17-keto steroids through two different pathways. The major active metabolites are estradiol and dihydrotestosterone (DHT). Route of Elimination: About 90% of a dose of testosterone given intramuscularly is excreted in the urine as glucuronic and sulfuric acid conjugates of testosterone and its metabolites; about 6% of a dose is excreted in the feces, mostly in the unconjugated form.

Testosterone propionate is used in veterinary practice in heifers in order to stimulate maximal growth. The administration of testosterone propionate can induce production of proteins related to male sexual development. Clinical trials have shown a decrease in plasma LH after the administration of testosterone propionate.

Absorption
Testosterone propionate presents a slow absorption from the intramuscular site of administration. This slow absorption is due to the presence of the less polar ester group. The absorption rate of testosterone propionate generates a frequent injection requirement when compared with testosterone enanthate or testosterone cypionate. It presents absorption parameters of AUC and residence time of 180-210 ng h/ml and 40-60 h, respectively.
Route of Elimination
About 90% of a dose of testosterone given intramuscularly is excreted in the urine as glucuronic and sulfuric acid conjugates of testosterone and its metabolites. From the rest of the dose, approximately 6% of a dose is excreted in the feces, mostly in the unconjugated form.
Volume of Distribution
The registered volume of distribution for testosterone propionate is in the range of 75-120 L/kg.
Clearance
Testosterone propionate has a reduced clearance rate compared to testosterone. The reported clearance rate is of approximately 2000 ml/min.
Biological Half-Life
Testosterone propionate possesses a relatively short half-life compared with other testosterone esters at approximately 4.5 days.

Absorption, Distribution and Excretion
Testosterone propionate presents a slow absorption from the intramuscular site of administration. This slow absorption is due to the presence of the less polar ester group. The absorption rate of testosterone propionate generates a frequent injection requirement when compared with testosterone enanthate or testosterone cypionate. It presents absorption parameters of AUC and residence time of 180-210 ng h/ml and 40-60 h, respectively.
About 90% of a dose of testosterone given intramuscularly is excreted in the urine as glucuronic and sulfuric acid conjugates of testosterone and its metabolites. From the rest of the dose, approximately 6% of a dose is excreted in the feces, mostly in the unconjugated form.
The registered volume of distribution for testosterone propionate is in the range of 75-120 L/kg.
Testosterone propionate has a reduced clearance rate compared to testosterone. The reported clearance rate is of approximately 2000 ml/min.

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Metabolism / Metabolites
As all testosterone esters, testosterone propionate is rapidly hydrolysed into free testosterone in plasma. Testosterone is metabolized to 17-keto steroids through two different pathways. The major active metabolites are estradiol and dihydrotestosterone (DHT).
Testosterone propionate is rapidly hydrolysed into testosterone. Testosterone is metabolized to 17-keto steroids through two different pathways. The major active metabolites are estradiol and dihydrotestosterone (DHT).
Route of Elimination: About 90% of a dose of testosterone given intramuscularly is excreted in the urine as glucuronic and sulfuric acid conjugates of testosterone and its metabolites; about 6% of a dose is excreted in the feces, mostly in the unconjugated form.

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Biological Half-Life
Testosterone propionate possesses a relatively short half-life compared with other testosterone esters at approximately 4.5 days.

Toxicity Summary
The effects of testosterone in humans and other vertebrates occur by way of two main mechanisms: by activation of the androgen receptor (directly or as DHT), and by conversion to estradiol and activation of certain estrogen receptors. Free testosterone (T) is transported into the cytoplasm of target tissue cells, where it can bind to the androgen receptor, or can be reduced to 5α-dihydrotestosterone (DHT) by the cytoplasmic enzyme 5α-reductase. DHT binds to the same androgen receptor even more strongly than T, so that its androgenic potency is about 2.5 times that of T. The T-receptor or DHT-receptor complex undergoes a structural change that allows it to move into the cell nucleus and bind directly to specific nucleotide sequences of the chromosomal DNA. The areas of binding are called hormone response elements (HREs), and influence transcriptional activity of certain genes, producing the androgen effects.

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Protein Binding
Even 98% of testosterone in plasma is bound to sex hormone-binding globulin and 2% remains unbound or bound to albumin and other proteins.

[1] Archives of General Psychiatry, 57, 133-140;

[2] Personality and Individual Differences, 28, 437-445;

[3] Am J Physiol Endocrinol Metab 2003 Jan 7;

[4] J Investig Med. 1997 Oct;45(8):441-7;

[5] J Clin Endocrinol Metab. 1986 Dec;63(6):1361-4;

[6] J Clin Endocrinol Metab. 1997 Feb;82(2):407-13;

[7] Am J Physiol Endocrinol Metab. 2002 Mar;282(3):E601-7;

[8] Curr Opin Clin Nutr Metab Care. 2004 May;7(3):271-7;

[9] Curr Pharm Biotechnol. 2004 Oct;5(5):459-70;

[10] Metabolism. 1991 Apr;40(4):368-77;

[11]] J Lab Clin Med. 1995 Mar;125(3):326-33;

[12] Zhonghua Nan Ke Xue. 2003;9(4):248-51.

Testosterone propionate appears as odorless white or yellowish-white crystals or a white or creamy-white crystalline powder. (NTP, 1992)
Testosterone propionate is a steroid ester.
Testosterone propionate is a slower-releasing anabolic steroid with a short half-life. It is a synthetic androstane steroid derivative of testosterone in the form of 17β propionate ester of testosterone. Testosterone propionate was developed initially by Watson labs, and FDA approved on February 5, 1974. Currently, this drug has been discontinued in humans, but the vet application is still available as an OTC.
Testosterone Propionate is a short acting oil-based injectable formulation of testosterone. Testosterone inhibits gonadotropin secretion from the pituitary gland and ablates estrogen production in the ovaries, thereby decreasing endogenous estrogen levels. In addition, this agent promotes the maintenance of male sex characteristics and is indicated for testosterone replacement in hypogonadal males. (NCI04)
An ester of testosterone with a propionate substitution at the 17-beta position.
An ester of TESTOSTERONE with a propionate substitution at the 17-beta position.
See also: Testosterone (has active moiety); Estradiol Benzoate; Testosterone Propionate (component of).

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Drug Indication
Testosterone propionate is used in veterinary practice in heifers in order to stimulate maximal growth.

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Mechanism of Action
The effects of testosterone in humans and other vertebrates occur by way of two main mechanisms: by activation of the androgen receptor (directly or as DHT), and by conversion to estradiol and activation of certain estrogen receptors. Free testosterone (T) is transported into the cytoplasm of target tissue cells, where it can bind to the androgen receptor, or can be reduced to 5alpha-dihydrotestosterone (DHT) by the cytoplasmic enzyme 5alpha-reductase. The areas of binding are called hormone response elements (HREs), and influence transcriptional activity of certain genes, producing the androgen effects.

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Pharmacodynamics
The administration of testosterone propionate can induce production of proteins related to male sexual development. Clinical trials have shown a decrease in plasma LH after the administration of testosterone propionate.

C22H32O3

344.495

344.235

57-85-2

5995

Typically exists as solid at room temperature

1.1±0.1 g/cm3

454.6±45.0 °C at 760 mmHg

118-123 °C

196.3±28.8 °C

0.0±1.1 mmHg at 25°C

1.538

4.9

0

3

3

25

621

6

O(C(C([H])([H])C([H])([H])[H])=O)[C@@]1([H])C([H])([H])C([H])([H])[C@@]2([H])[C@]3([H])C([H])([H])C([H])([H])C4=C([H])C(C([H])([H])C([H])([H])[C@]4(C([H])([H])[H])[C@@]3([H])C([H])([H])C([H])([H])[C@@]21C([H])([H])[H])=O

PDMMFKSKQVNJMI-BLQWBTBKSA-N

InChI=1S/C22H32O3/c1-4-20(24)25-19-8-7-17-16-6-5-14-13-15(23)9-11-21(14,2)18(16)10-12-22(17,19)3/h13,16-19H,4-12H2,1-3H3/t16-,17-,18-,19-,21-,22-/m0/s1

[(8R,9S,10R,13S,14S,17S)-10,13-dimethyl-3-oxo-1,2,6,7,8,9,11,12,14,15,16,17-dodecahydrocyclopenta[a]phenanthren-17-yl] propanoate

Enarmon Androlon Testosterone propionate

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)