GHRP-6 and Hexarelin

Growth Hormone Releasing Peptide-6 (GHRP-6) is one of the best growth hormone secretagogues that have the unique potential of stimulating the release of growth hormone (GH) by two entirely different mechanisms. While GHRP-6 has the ability to amplify the natural growth hormone releasing hormone (GHRH) signal transduction pathway, it can also act as a functional antagonist of the hormone resulting in inhibition of somatostain (GH secretion).

Growth hormone releasing peptide-6 is well known to have a positive influence on the feedback loop that signals inhibition of growth hormone release and can be used for stimulating the natural production of GH again when the same has been inhibited by long term use of synthetic drugs. Moreover, it also has the ability to stimulate a significant improvement in the level of normal pulsatile physiological secretion by its hypothalamic action and pulsatile secretory bursts of growth hormone. In addition to that, it can protect neurons and stimulate strength like some steroids in the Dihydrotestosterone family.^[1]

GHRP-6 is commonly used by sportsmen, especially those into bodybuilding and strength athletics, to lose fat and weight in a safe and effective manner besides rejuvenating and strengthening of joints, bone mass, and connective tissue. It is used after a steroid cycle with growth hormone as the primary or only compound and leads to re-establishment of the organic growth hormone levels to normal besides improving the level of insulin-like growth factor 1 (IGF-1) and may be stacked with low doses of growth hormone for enhancing its effects and help users stay away from exhaustion, a common complication with GH. When injected, it can increase the level of basal rate by four times and the IGF-1 level remains increased within a week after injection. The best part is that it can be administered not only independently but also in a combination with anabolic steroids, commonly during a bulking cycle.^[2]

A concurrent administration of GHRH and GHRP-6 can result in the synergistic release of GH from pituitary stores.^[3] It is worthwhile to note that the GHRPs (GHRP-6, GHRP-2 and Hexarelin) come in only one half-life form and potent of generating a growth hormone pulse that lasts only for a few hours and therefore re-administration of a GHRP is necessary to bring an effect on additional pulses. Hydrolysis by trypsin-like enzymes could not affect the result of stimulation as growth hormone is released in a pulsatile way and a higher level of GH is observed between 15-30 minutes after administration of GH-RH analogues in a subcutaneous manner.^[4]

Hexarelin, on the other hand, is a powerful GH-releasing peptide, that has the chemical name of L-Histidyl-2-methyl-D-tryptophyl-L-alanyl-L-tryptophyl-D-phenylalanyl-L-lysinamide; {HIS}{D-2-ME-TRP}{ALA}{TRP}{d-PHE}{LYS}-NH2 and the molecular formula of C₄₇H₅₈N₁₂O₆. ^[5]This peptide is rated better than growth hormone releasing hormone and growth Hormone Releasing Peptide-6 as it can easily and dramatically stimulate the secretion of GH, ACTH (adrenocorticotropic hormone), cortisol, and prolactin during sleep. Moreover, it is believed to be long-lasting and effective than GHRH and users of Hexarelin can experience a potent GH releasing peptide combination when they combine Hexarelin with GHRP-6 rather than combining GHRH with GHRP-6.^[6]

This is because the former combination is linked with circulating IGF-1 concentration improvements in the context of serum IGF-1, IGF-binding protein-3 concentrations, and promotion of linear growth besides being equally effective in reestablishing the levels of Insulin-like development factor-I and growth hormones. Use of this compound is also admired for its ability to promote growth of new muscle fibers, increase size of existing muscle fibers, and improve body strength and on-field performance. Furthermore, Hexarelin is also found to be second to none when it comes to promotion of neural protection, joint rejuvenation, protection and healing, and fat reduction and is best used in doses of 200 mcg per day when used via subcutaneous injections The best thing about this peptide is that its unique amino acid sequence promotes the level of growth hormone in the body without shutting down the body’s own production.

Hexarelin, unlike GHRP-6, does not induce food intake as it has the potential of increasing the levels of ghrelin that are responsible for faster emptying of the gastric system and the feeling of hunger. In addition to that, use of Hexarelin is related to inhibition of the increase in diastolic pressure of the left ventricular end as with coronary perfusion pressure, reactivity of the coronary vasculature to angiotensin and releasing the creatine kinase from the perfusate of the heart. It can even prevent the fall in release of prostacyclin besides improving recovery of contractility. Few studies in the recent past have even suggested that this compound has cardioprotective actions. ^[7] Hexarelin is considered to be the strongest peptide when compared to GHRP-2 and GHRP-6 for stimulating GH secretion. On the other hand, GHRP-6 is less strong than GHRP-2.

At the saturation dose 100mcg, GHRP-6 does not lead to an increase in the levels of cortisol and prolactin but it can do so at higher dosages though the rise is still within the normal range. Hexarelin, on the other hand, has the highest potential to increase prolactin and cortisol even at the 100mcg saturation dosage and this rise would reach the higher levels of what is defined as normal. While Growth hormone releasing peptide-6 can be used at 100mcg saturation doses three or four times a day without the risk of desensitization, Hexarelin is characterized by desensitization though it is believed that there is no loss of sensitivity in the long term at saturation doses. However, Hexarelin dosages even at 100mcg three times a day can bring some down regulation within 14 days. GHRP-6 chronic use at 100mcg dosed several times a day every day would not lead to significant prolactin or cortisol problems or pituitary problems or desensitization. In the interest of users, it is commonly advised that the best option is to use a GHRP + a GHRH analog pre-bed (to support the night time pulse), once or twice throughout the day, which is ideally be done on either an empty stomach or with only protein in the stomach as fats and carbohydrates tend to blunt the release of growth hormone.