Copper Peptide Hair Growth Serum (GHK Cu & AHK Cu) Peptide Therapy for Hair Growth: Explore Your Options The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline : . Dr. Shintre breaks down what it is and why it works. ? A copper based peptide that naturally occurs in your Hair Growth Serum Intense with Copper Peptide GHK Cu Hair Growth Serum Intense with Copper Peptide GHK Cu