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OTR-AC (MK-29, OSTARINE-O-ACETATE) Solution, 750mg (25mg/mL)

OTR-AC (MK-29, OSTARINE-O-ACETATE) Solution, 750mg (25mg/mL)

Regular price €49,99
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OTR-AC, also known as MK-2866 Ester, is MK-2866 (Ostarine) that has undergone esterification (the process of combining an organic acid with an alcohol). This chemical process is used to maximize potency and extend the half-life (the time required for a quantity to reduce to half of its initial value) of a substance. Due to this process, the ester version of ostarine has the capacity to remain bioactive ten times longer. This results in benefits such as reduced dosing frequency and more stable blood levels.

How OTR-AC Works 
As the ester version of the selective androgen receptor modulator (SARM) ostarine, OTR-AC is more potent and has longer-lasting effects. By binding to proteins in the body known as androgen receptors, it stimulates the formation of muscle tissue. This, in turn, leads to an increase in muscle mass and strength.

Research on OTR-AC
Increase in Muscle Mass and Strength 
Studies suggest that OTR-AC, along with other SARMs, increases muscle mass and strength by stimulating the formation of muscle tissue:

  • In adult rats, the administration of SARMs, including OTR-AC, resulted in an increase in lean muscle mass and a decrease in body fat percentage.
  • In older male and female rats, OTR-AC administration resulted in increased lean muscle mass, decreased fat mass, and significant improvements in their ability to climb stairs.
  • Studies showed that OTR-AC may help increase muscle mass in rats with cancer cachexia (muscle wasting).
  • In older male and female rats, OTR-AC significantly improved total lean body mass and physical function.
  • In rats that had their ovaries surgically removed, OTR-AC improved muscle tissue.
  • In rats, OTR-AC increased muscle mass by enhancing the production of muscle cells.

Reduction of Body Fat 
Aside from helping gain muscle mass, OTR-AC has also been found to reduce overall body fat:

  • In Phase I and II clinical trials, OTR-AC has demonstrated promising results in increasing total lean body mass, decreasing total tissue fat percentage, and enhancing functional performance.
  • A review of studies showed that OTR-AC can help increase lean body mass and reduce body fat in overweight rats.
  • In a phase 2a study, the administration of OTR-AC along with other SARMs resulted in increased lean fat mass and decreased body fat percentage.
  • In male rats, OTR-AC increased fat cell breakdown by improving lipid metabolism and affecting the release of adiponectin (a hormone that regulates fatty acid breakdown).

Improvement of Bone Health 
Studies suggest that OTR-AC can help stimulate bone formation and protect against bone disorders:

  • In rats that had their ovaries surgically removed, OTR-AC administration resulted in improved bone healing.
  • In a rat model for aged male osteoporosis, both OTR-AC and testosterone treatments improved bone healing by increasing callus volume and area, bone volume and density, and bone width.
  • In a rat model of postmenopausal osteoporosis, high doses of OTR-AC for 5 weeks resulted in increased bone volume, density, and bone mineral density.


Reduction of Cholesterol Levels 
Evidence suggests that OTR-AC can help lower cholesterol levels, especially low-density lipoprotein (bad cholesterol):

  • In older male and female rats, OTR-AC administration resulted in a significant reduction in low-density lipoprotein levels.
  • In rats that had their ovaries surgically removed, OTR-AC treatment reduced blood cholesterol levels.



Half Life
24 hours.

This material is sold for use in laboratory research only. Terms of sale apply. Not for human consumption, nor for medical, veterinary use. Please use with our DISCLAIMER before ordering.

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