Pediatric Implications of Normal Insulin GH IGF Axis Physiology Endotext NCBI Bookshelf Growth Hormone and IGF 1 Actions in the Brain and Neuropsychiatric Diseases Physiology American Physiological Society Targeting growth hormone function: strategies and therapeutic applications Signal Transduction and Targeted Therapy IGF 1 vs. HGH Which is Better for Growth and Fat Loss? HRT Before vs. after 3 months of GHK Cu peptide therapy smoother texture, more even tone, and skin that looks healthier overall. Small peptide, big difference