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.