Comment · Thu, January 22, 2015 · Ceretropic
Semax and libido
Original post in this thread
[deleted] · 3 points
So I've been taking Semax (nasal spray version from Ceretropic) daily for approximately 2 weeks now in dosages of 600-1000mcg and I've noticed a decrease in libido.
Not sure if it's caused by Semax but I'll stop using it for now to see if anything changes.
Was wondering if any of you had similar experiences with Semax?
What they were answering
EnLilaSko · 1 points
https://www.ncbi.nlm.nih.gov/pubmed/21629206 - ACTH 4-10 seems to be an agonist.
I got most of the info from the site you link in the product description.
Also found this on wiki -
http://www.sciencedirect.com/science/article/pii/S0014299912000544
Apparently, no data are available concerning the melanocortin receptors involved in the above described effects of Semax. However, Semax is identical to a melanocortin analogue that had been studied by Adan et al. (1994), and found to antagonize the action of alpha-MSH on the melanocortin MC4 and MC5 receptors, but not on the melanocortin MC3 receptors, both in “in vitro” and in “in vivo” models (alpha-MSH-induced cAMP accumulation in embryonal kidney cells, and alpha-MSH-induced excessive grooming behavior in rats, respectively). These data are intriguing and further investigations are needed in order to establish what melanocortin receptors (MC3?) are involved, and how (partial agonism?), in the mechanism of action of Semax in hypoxic conditions.
u/MisterYouAreSoDumb · Ceretropic
That's MSH/ACTH(4-10). Other ACTH(4-10) analogs antagonize MC4.
Identification of Antagonists for Melanocortin MC3, MC4, and MC5 Receptors
> Two peptides, [D-ArgS]ACTH(adrenocorticotrope hormone)-(4-10) and [ProS'I°,Glyg]ACTH-(4-10), antagonized the
action of a-MSH on the melanocortin M C 4 and MC 5 receptors, but not the melanocortin MC3 receptor. [Ala6]ACTH-(4-10)
inhibited the a-MSH activation of the melanocortin MC 3 and MC 5, but only weakly antagonized the activation of the
melanocortin M C 4 receptor. [Phe-I7]ACTH-(4-10) antagonized the melanocortin MC3, MC 4 and MC 5 receptors equally well.
These antagonists were also tested to block a behavioral response induced by a-MSH, a-MSH-induced excessive grooming
behavior in rats was inhibited by [Phe-Iv]ACTH-(4-10), [D-ArgS]ACTH-(4-10) and [ProS'm,Gly9]ACTH-(4-10), but not by
[Ala6]ACTH-(4-10). This suggests that a-MSH-induced excessive grooming behavior is mediated by melanocortin MC 4
receptors.
So it looks like the modifications to the ACTH(4-10) peptide alter the melanocortin effects. Some are agonists, while others are antagonists. Semax appears to be an antagonist. So it is possible that is the reason some people are getting sex drive changes.