IGF-1-LR3
Growth Factor ResearchCAS 946870-92-4
Available sizes: 0.1 mg, 1 mg
IGF-1 LR3
Engineered to escape the binding proteins
IGF-1 is the principal mediator through which growth hormone acts on tissue, and its availability is controlled by a family of six binding proteins that hold the great majority of it inactive at any moment. That regulation is the system, not a nuisance.
LR3 defeats it deliberately: Arg³ in place of Glu³ reduces binding protein affinity by orders of magnitude, and the 13-residue N-terminal extension further alters its behaviour. The result circulates free and persists far longer.
What that means for interpretation
Because the analogue bypasses the regulatory layer, results obtained with it describe unregulated IGF-1 receptor signalling rather than IGF-1 physiology. That is a legitimate and often desirable experimental condition, but it is a distinction that has to be stated when comparing to native IGF-1 work.
IGF-1 receptor signalling in cell culture, where sustained availability is wanted
Myogenesis and satellite cell studies
Binding protein biology, using LR3 as the low-affinity contrast
Growth hormone axis research, as the downstream readout
Read alongside
The GHRH analogues Sermorelin, CJC-1295 and Tesamorelin act upstream of this molecule, as do the secretagogues. IGF-1 LR3 is where that axis terminates.
Documentation and verification
Certificates of Analysis are published for tested products and batches. A certificate is a batch-specific record: it reports what was measured, by which method, on a stated date, against a batch identifier. It is evidence about the sample analysed at the time of analysis, and it is silent on attributes it does not list and on what has happened to the material since.
The batch number is the field that connects the document to a physical vial. Where the identifier on a vial does not appear on a certificate, the certificate does not describe that vial, however thorough the analysis behind it was. Batch records can be searched directly, and the guides below explain what each field establishes and what it does not.
- Verify a batchSearch a batch number for the certificate records published against it.
- How to read a certificate of analysisWhat each field reports, and the limits of what a certificate can establish.
- Certificate, specification and safety data sheetThree documents that answer three different questions.
- Storage and handlingWhat defined storage conditions mean, and why cold slows degradation.
- Batch numbers and traceabilityHow an identifier ties material to the analysis describing it.
Supplied for laboratory research use only. Not for human or veterinary use.