GLP-3 R Phase 2: −28.7%143 Compounds · 5 Layers>98% HPLC All VialsFree Shipping $200+Third-Party Test ReportsResearch Use OnlyCAS Numbers VerifiedGHK-Cu: 4,000+ GenesGLP-3 R Phase 2: −28.7%143 Compounds · 5 Layers>98% HPLC All VialsFree Shipping $200+Third-Party Test ReportsResearch Use OnlyCAS Numbers VerifiedGHK-Cu: 4,000+ Genes
Guide7 min read2026-04-16

HGH Fragment 176-191: Lipolytic Research Peptide

The C-terminal fragment of human growth hormone retains lipolytic activity without the full GH effects on IGF-1 or insulin. Here is why researchers care.

Isolating One Function From a Multi-Function Hormone

Full-length human growth hormone produces multiple overlapping effects: lipolysis, IGF-1 induction, insulin resistance, cellular proliferation. Research that wants to study one of these effects in isolation has to either use antagonists or use a fragment that retains only the target function.

HGH Fragment 176-191 is the second approach. The research-grade peptide is available as HGH Fragment 176-191 5mg.

The C-Terminal Region

Human growth hormone is a 191-amino-acid protein. Structure-function research has mapped different regions to different effects:

  • N-terminal / residues 1-15: Insulin antagonism and glucose metabolism effects
  • Middle region: IGF-1 induction via hepatic GH receptor activation
  • C-terminal / residues 177-191: Lipolytic activity on adipose tissue

The 176-191 fragment captures the lipolytic region without the segments driving IGF-1 or glucose effects.

Lipolytic Mechanism

The fragment's mechanism involves:

  • Beta-3 adrenergic activation in adipose tissue
  • Hormone-sensitive lipase upregulation
  • Triglyceride hydrolysis and fatty acid release
  • Reduced lipogenesis via inhibition of acetyl-CoA carboxylase

The net effect is accelerated fatty acid mobilization without the systemic metabolic effects of full GH.

Why This Matters for Research Design

In full-GH research, teasing apart lipolysis vs IGF-1 vs insulin effects is difficult because all three occur simultaneously. The fragment approach asks: what happens when only the lipolytic axis is engaged?

This enables:

  • Lipolysis dose-response studies without IGF-1 confounding
  • Adipose-specific research without systemic growth effects
  • Comparative research against full-length GH compounds

Handling Notes

Lyophilized HGH Fragment is stable at −20°C long-term. Reconstitution with bacteriostatic water is standard. >98% HPLC purity is the research grade.

For research protocols targeting the lipolytic axis specifically, see HGH Fragment 176-191 5mg.