MK677 known as Ibutamoren is a well-known compound in Sports and Nutrition industry. People have acknowledged great results while using ibutamoren but there is a lot of articles about its “darkside”. Are there any side effects? Is it a perfect supplement for quick results? Or is it just needless supplement that is “not working”. Read this blog post to find out.

bodybuilding mk677

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What is MK677?

MK-677 can be also called Ibutamoren or Nutrabol. It is a very popular compound on the market that boosts growth hormone. There are even more advantages of this product that will be described later in this article. If you like the more chemical stuff, then the next paragraph was written for you.

mk677 and yk11
MK-677 from TWP

Ibutamoren (developmental code names MK-677MK-0677L-163,191; former tentative brand name Oratrope) is a potent, long-acting, orally-active, selective, and non-peptideagonist of the ghrelin receptor and a growth hormone secretagogue, mimicking the growth hormone (GH)-stimulating action of the endogenoushormoneghrelin. It has been shown to increase the secretion of several hormones including GH and insulin-like growth factor 1 (IGF-1) and produces sustained increases in the plasma levels of these hormones without affecting cortisol levels.

Ibutamoren is frequently displayed in the SARMS category, however, MK-677 is not a Sarm. It usually works better with the Sarms and that is why it is sold as a Sarm to be more clear. Just like for example Stenabolic.

One of the most notable claims made about Ibutamoren is that it can increase the secretion of growth factors-1 (IGF-1) and growth hormone (GH).

It does this by imitating the way the ghrelin hormone works. This allows it to bind onto one of the brain’s dedicated ghrelin receptors (GHSR). Once activated, GHSR then stimulates the production of the growth hormone in the brain.

Compound Profile: Recommended Dosage: CAS Number: Half-life:
MK-677 (Ibutamoren) 10 to 20mg per day 159634-47-6 6 hours

It’s interesting to note that GHSR is especially present in the brain regions. This region functions like memory, biological rhythms, mood, pleasure, appetite, and cognition.

Therefore, among all benefits, the most interesting is how MK-677 supporting the growth hormone.

To better understand how MK-677 supports the GH, we will have a look at human growth hormone and what it is responsible for.

Human Growth hormone

Growth hormone release is not continuous; it is released in a number of ‘bursts’ or pulses every three to five hours. This release is controlled by two other hormones that are released from the hypothalamus (a part of the brain): growth hormone-releasing hormone, which stimulates the pituitary to release growth hormone, and somatostatin, which inhibits that release.

Growth hormone levels are increased by sleep, stress, exercise and low glucose levels in the blood. They also increase around the time of puberty. Growth hormone release is lowered in pregnancy and if the brain senses high levels of growth hormone or insulin-like growth factors already in the blood.

So, now we know that growth hormone is responsible for growth in the whole body and not only muscles.

Naturally, MK677 may have an effect on these functions as well, whether it’s to increase or diminish them.

What makes MK-677 so unique is the fact that it can increase GH levels. But it does not disrupt the action of other hormones in your body such as cortisol which was found on numerous websites about MK-677.

If it was influencing other hormones such as cortisol, it could result in side effects. However, there have not been found any side effects when it comes to MK-677! These would include reduced immune function, impaired wound healing and a diminished ability to learn and memorize information and even more. Thankfully, that’s unlikely to happen with Ibutamoren. There is a study proving that cortisol has not been significantly changed.

A potent, orally active growth hormone (GH) secretagogue L-163,191 belonging to a recently synthesized structural class has been characterized. L-163,191 releases GH from rat pituitary cells in culture with EC50 = 1.3 +/- 0.09 nM and is mechanistically indistinguishable from the GH-releasing peptide GHRP-6 and the prototypical nonpeptide GH secretagogue L-692,429 but clearly distinguishable from the natural GH secretagogue, GH-releasing hormone. L-163,191 elevates GH in dogs after oral doses as low as 0.125 mg/kg and was shown to be specific in its release of GH without significant effect on plasma levels of aldosterone, luteinizing hormone, thyroxine, and prolactin after oral administration of 1 mg/kg. Only modest increases in cortisol were observed. Based on these properties, L-163,191 has been selected for clinical studies.

How does MK-677 work?

As mentioned, MK-677 works by imitating the activity of ghrelin. In case you’re wondering, ghrelin is a naturally occurring hormone.

It functions as a neuropeptid