In growth hormone research, two analogs of Growth Hormone-Releasing Hormone (GHRH) are incredibly popular: CJC-1295 with DAC and Modified GRF (1-29) (which is CJC-1295 without DAC). While they share the same base sequence, their pharmacokinetic profiles are completely different.

## Modified GRF (1-29): The Pulsatile Stimulator

Modified GRF (1-29) has a very short half-life of approximately 30 minutes. In research models, this mimics the body's natural, pulsatile release of GHRH. It causes a sharp, immediate spike in GH levels that quickly returns to baseline. Researchers prefer this for studies requiring natural, episodic GH pulses.

## CJC-1295 with DAC: The Extended Release

DAC stands for Drug Affinity Complex. It is a lipid molecule attached to the peptide that binds to albumin in the blood. This prevents the peptide from being rapidly degraded by enzymes (DPP-IV inhibition). As a result, CJC-1295 with DAC has a massive half-life of up to 8 days.

Instead of a sharp pulse, it creates a sustained, elevated "bleed" of GH over several days. This is highly useful for researchers studying the effects of chronic, stable GH elevation versus acute pulsing.

Find both Modified GRF (1-29) and CJC-1295 with DAC for your endocrinology research at Pure Peptides UK.

*Disclaimer: Strictly for in vitro laboratory research.*