Figure 2. [Factors that stimulate and suppress GH secretion under physiological conditions.]. Endotext NCBI Bookshelf My Second Week of GHK CU & NAD+ Injections 50mg GHK Cu Vial Blue Copper Peptide Face Serum Age Aging Moisturizing Repairing for Skin Care Serum Facial Care Kit d Growth hormon Central regulate metabolism Encyclopedia MDPI The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline