P21 vs VIP (Vasoactive Intestinal Peptide)
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
P21
P21 is a synthetic peptide derived from Cerebrolysin, specifically designed to mimic the neurotrophic effects of the parent compound. It promotes neurogenesis and has shown cognitive-enhancing properties in research.
Full details →VIP (Vasoactive Intestinal Peptide)
VIP is a 28-amino acid neuropeptide with wide-ranging effects throughout the body. It acts as a neurotransmitter, neuromodulator, and immune regulator with particular importance in gut and lung function.
Full details →Side-by-Side Comparison
| Aspect | P21 | VIP (Vasoactive Intestinal Peptide) |
|---|---|---|
| Mechanism | Inhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity. | Binds to VPAC1 and VPAC2 receptors to modulate immune responses, regulate circadian rhythms, promote vasodilation, and support barrier function in gut and lungs. Has potent anti-inflammatory effects. |
| Typical Dosage | Research protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks. | Intranasal: 50-200mcg 1-3 times daily for chronic inflammatory conditions. Some protocols use subcutaneous administration. Dosing varies by condition. |
| Administration | Can be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously. | Intranasal is most common for inflammatory conditions. Subcutaneous injection also used. Must be stored cold and protected from light. |
| Side Effects | Limited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue. | May cause nasal irritation, flushing, headache, or temporary diarrhea. Generally well-tolerated at standard doses. |
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