Pre mixed peptide pens are the best way to deliver your peptides. These pens are portable, easy to use and are more convenient than using vials with syringes. They have a special cartridge that contains a pre mixed peptide and come with a needle inside the case. The pen kits also contain a dial that allows you to set the dose accurately. The pens are also refillable and single cartridges can be purchased to top up the kit.
The peptide PEN (Gly-Glu-Pro-Pro-Lys-Pro) is an abundant neuropeptide in the hypothalamus and hippocampus, where it acts as an appetite stimulant and a pheromone that controls feeding behavior. We showed that PEN bound and activated GPR83, a heterotrimeric G protein-coupled receptor for neuropeptides, in mouse hypothalamic membranes. Subnanomolar concentrations of PEN increased the GTPgS binding of mGPR83, and this effect was desensitized by 30 min (Fig. 1D).
Moreover, we found that PEN binds and activates GPR171 in cultured neurons of the PVN. These results suggest that PEN and GPR171 are colocalized in a subset of neurons in the PVN and that both peptides modulate sEPSC amplitudes through distinct mechanisms. The fact that PEN and bigLEN, another proSAAS-derived peptide with biological activity through an unidentified receptor (29), have similar signaling properties may have important physiological implications. In addition, mPEN and bigLEN both undergo agonist-induced endocytosis and are likely to co-secrete in the PVN. This functional interplay between the two receptors may enable a bidirectional regulation of synaptic activity in the PVN.