CJC-1295 Without DAC

CJC-1295 Without DAC | Buy CJC-1295 No DAC UK | Modified GRF (1-29) | Research Use Only

CJC-1295 Without DAC — also known as Modified GRF (1-29), Mod GRF (1-29), and tetrasubstituted GRF (1-29) — is a synthetic 29-amino acid analogue of human GHRH (1-29) incorporating four targeted amino acid substitutions that confer robust resistance to DPP-4 enzymatic cleavage, while preserving full GHRH receptor activity and extending effective half-life from the sub-10-minute window of native GRF (1-29) to approximately 30 minutes. Unlike its albumin-binding counterpart CJC-1295 With DAC, the no-DAC variant produces discrete, physiologically pulsatile GH release events — making it the preferred GHRH-class research tool for studying GH axis pulse dynamics, somatotroph receptor pharmacology, and GHRH-R-mediated signalling in controlled, short-duration experimental models. Buy CJC-1295 Without DAC in the UK from Peptides Lab UK with >99% HPLC-verified purity, batch-specific COA, and fast UK dispatch for laboratory and in vitro research use only.

Distributed by Peptides Lab UK in a high-purity lyophilised format, for laboratory research use only. This compound is handled in controlled settings for in vitro and pre-clinical studies, with no applications in human or veterinary medicine. Each batch undergoes rigorous quality analysis to ensure >99% purity (HPLC verified).

What Is CJC-1295 Without DAC (Modified GRF 1-29)?

Modified GRF (1-29), often abbreviated as Mod GRF (1-29) and originally known as tetrasubstituted GRF (1-29), is a 29-amino acid peptide analogue of growth hormone-releasing hormone. It is a modified version of the shortest fully functional fragment of GHRH — GRF (1-29), also known as Sermorelin — with the first 29 amino acids of GHRH having been shown to be equally potent as the full 44-amino acid GHRH structure. GRF (1-29) itself was found to suffer from rapid metabolic clearance, leading to the synthesis of analogues with substituted amino acids more resistant to enzymatic cleavage.

CJC-1295 Without DAC, also known as Modified GRF (1-29), is a tetrasubstituted GHRH analogue that binds the GHRH receptor and activates cAMP/PKA-mediated GH synthesis, essentially mimicking the hypothalamic release signal but with enhanced stability against enzymatic degradation.

Modified GRF (1-29) is a synthetic modification of growth hormone releasing factor with D-Ala, Gln, Ala, and Leu substitutions at positions 2, 8, 15, and 27 respectively — substitutions that create a significantly more stable and longer-acting compound than either native GRF (1-29) or Sermorelin, while maintaining the same receptor interaction profile at the GHRH receptor.

An important terminological note for the research community: Modified GRF (1-29) is identical to the portion of CJC-1295 DAC that is not bound to the maleimidopropionamide (MPA) group, minus the terminal lysine. The presence of a free terminal lysine in a literal CJC-1295 peptide without DAC conjugation would have the opposite effect of DAC — it would drastically reduce the active life of the peptide to that of Sermorelin. What is correctly referred to as CJC-1295 without DAC in research and commercial contexts is therefore Modified GRF (1-29).

As a research compound, CJC-1295 Without DAC UK is the most widely used pulsatile GHRH-class secretagogue in pre-clinical GH axis research, and the reference GHRH component in the most extensively studied dual-pathway GH secretagogue combination — CJC-1295 No DAC + Ipamorelin — which is described in a separate Peptides Lab UK product listing.

How Does CJC-1295 Without DAC Work?

The Four Amino Acid Substitutions — Mechanism of Stability

Four targeted amino acid substitutions — D-Ala² (position 2), Gln⁸ (position 8), Ala¹⁵ (position 15), and Leu²⁷ (position 27) — give CJC-1295 Without DAC dramatically improved resistance to DPP-IV proteolytic cleavage compared to native GRF (1-29), which has a half-life of under 10 minutes. The D-alanine substitution at position 2 is specifically directed at blocking the primary DPP-4 cleavage site, while the remaining substitutions prevent additional enzymatic attack at susceptible positions and reduce oxidative degradation during storage and in vivo.

GHRH Receptor Binding and cAMP/PKA Signalling

Modified GRF (1-29) acts to increase growth hormone production and release by binding to the growth hormone-releasing hormone receptor on cells in the anterior pituitary — the same GHRHR target as native GHRH, Sermorelin, and Tesamorelin. Receptor engagement activates the Gs/adenylate cyclase pathway, increasing intracellular cAMP and engaging PKA-linked phosphorylation events that drive both GH gene transcription and pulsatile secretory granule exocytosis from somatotroph cells.

High GHRH-R Selectivity — No GHS-R1a Cross-Reactivity

Modified GRF (1-29) demonstrates high selectivity for GHRHR, with minimal cross-reactivity to other pituitary hormone receptors including the growth hormone secretagogue receptor (GHS-R1a) that mediates the effects of ghrelin and GHRPs such as Ipamorelin. This receptor selectivity makes it an ideal clean GHRH-R agonist for studies where the specific contribution of the GHRH pathway needs to be isolated from ghrelin/GHS-R1a biology.

Physiological Pulsatile GH Release Architecture

Unlike longer-acting formulations, the design of Modified GRF (1-29) emphasises short-duration action to preserve the pulsatile nature of GH release, which is critical for metabolic homeostasis. Its shorter duration of action more closely mimics the pulsatile nature of endogenous GHRH secretion, thereby supporting physiological episodic GH release patterns — in contrast to CJC-1295 with DAC, which produces sustained GH elevation with days-long GHRH-receptor occupancy.

Somatostatin Feedback Preservation

The no-DAC variant’s short half-life ensures GH is released in discrete bursts that respect somatostatin’s inhibitory feedback — an important distinction in research models where physiological GH axis dynamics and the somatostatin/GHRH interplay are the experimental focus. The pulsatile GH release profile is considered by many researchers to more closely mirror the natural hypothalamic-pituitary-somatotroph communication cycle than sustained GHRH-receptor stimulation.

What Does CJC-1295 Without DAC Do in Research?

In laboratory and pre-clinical settings, CJC-1295 Without DAC has been studied as the prototypical pulsatile GHRH-class secretagogue for GH axis biology. Research has examined its role in:

• GHRH receptor binding, Gs/adenylate cyclase activation, and cAMP/PKA signalling pathway studies
• Physiological pulsatile GH secretion modelling and somatotroph biology investigations
• GH and IGF-1 axis regulation and downstream anabolic signalling research
• DPP-4 resistance profiling and GHRH analogue structural pharmacology studies
• Somatotroph proliferation, GH mRNA transcription, and pituitary reserve research
• GH pulsatility architecture — pulse amplitude, frequency, trough levels, and inter-pulse intervals
• Somatostatin feedback dynamics and GHRH/somatostatin interplay modelling
• Metabolic pathway research — lipid oxidation, glucose homeostasis, and anabolic signalling
• GH axis ageing, somatopause, and GHRH pulse amplitude decline studies
• Dual-pathway synergy research when combined with GHS-R1a agonists such as Ipamorelin
• Comparative GHRH analogue pharmacology — Sermorelin, Tesamorelin, and CJC-1295 DAC

CJC-1295 Without DAC and Pituitary Somatotroph Biology

Research in GHRH knockout mice using the CJC-1295 backbone demonstrated that administration caused an increase in total pituitary RNA and GH mRNA, suggesting that proliferation of somatotroph cells had occurred — as confirmed by immunohistochemistry — establishing that the tetrasubstituted GHRH scaffold acts not only on acute GH release but also on transcriptional upregulation of GH gene expression and pituitary somatotroph reserve, findings directly relevant to the no-DAC variant’s receptor biology.

CJC-1295 Without DAC and DPP-4 Resistance Research

Research that led to the identification of the tetrasubstituted GRF backbone confirmed that all maleimido derivatives of hGRF(1-29) sharing the same four amino acid substitutions showed enhanced in vitro stability against DPP-IV and retained bioactivity in GH secretion assays in cultured rat anterior pituitary cells — establishing that the tetrasubstituted scaffold itself is responsible for DPP-4 resistance, independent of the DAC albumin-binding moiety.

CJC-1295 Without DAC and the Dual Receptor Research Model

CJC-1295 Without DAC engages the GHRH receptor pathway — activating cAMP/PKA-mediated GH gene transcription and vesicle exocytosis — while having no cross-reactivity with the GHS-R1a ghrelin receptor. When combined with Ipamorelin in dual-pathway research models, the two compounds engage both the cAMP pathway via GHRHR and the calcium signalling pathway via GHS-R1a simultaneously on the same somatotroph cell population — producing a synergistic GH pulsatility profile that neither compound achieves independently.

CJC-1295 Without DAC and Metabolic Research Models

Exploratory applications for Modified GRF (1-29) in pre-clinical research include models of growth hormone deficiency, HIV/AIDS-associated wasting and cachexia, idiopathic short stature, and metabolic syndrome — reflecting the breadth of GH axis research contexts in which physiological pulsatile GHRH stimulation is a relevant experimental tool.

What Do Studies Say About CJC-1295 Without DAC?

The published evidence base for CJC-1295 Without DAC draws on both the direct characterisation of the tetrasubstituted backbone and the extensive clinical and pre-clinical literature generated for CJC-1295 with DAC, which shares the same four amino acid substitutions and GHRH receptor pharmacology.

The Foundational Characterisation Study

The 2005 study by Jetté et al. that identified CJC-1295 as a long-lasting GRF analogue via albumin bioconjugation simultaneously confirmed the pharmacological profile of the tetrasubstituted GRF backbone — showing a 4-fold increase in GH area under the curve over a 2-hour period compared to native hGRF(1-29) in rats, with all three maleimido derivatives of the same tetrasubstituted scaffold demonstrating enhanced DPP-4 stability and full GHRH receptor bioactivity in anterior pituitary cell assays. This established the four amino acid substitutions as conferring substantially enhanced in vitro and in vivo potency independent of the DAC modification.

CJC-1295 Backbone Clinical Data — Relevant to the No-DAC Research Profile

Two randomised, placebo-controlled, double-blind, ascending-dose clinical trials of CJC-1295 DAC — which shares the same tetrasubstituted GHRH backbone as the no-DAC variant — produced dose-dependent increases in mean plasma GH concentrations of 2 to 10-fold for 6 days or more, and mean IGF-1 concentrations of 1.5 to 3-fold for 9–11 days. The studies confirmed the GHRH receptor pharmacological profile of the tetrasubstituted scaffold that underpins both variants, with the no-DAC form studied as the pulsatile delivery model and the DAC form providing the prolonged pharmacokinetic extension of that same receptor biology.

Pulsatile GH Architecture — Why the No-DAC Profile Matters

Research has confirmed that CJC-1295 Without DAC preserves the pulsatile nature of GH release — a feature considered critical for maintaining physiological GH axis dynamics, since the amplitude and frequency of GH pulses govern downstream effects on lean body mass, metabolic rate, and IGF-1 axis regulation. The no-DAC variant’s short ~30-minute effective half-life supports GH pulse patterns that more closely resemble endogenous GHRH-mediated secretion events than either CJC-1295 DAC or direct exogenous GH administration.

Sermorelin vs CJC-1295 Without DAC — The Research Upgrade

Compared to Sermorelin — the unmodified GRF (1-29) reference compound with a half-life of less than 10 minutes — CJC-1295 Without DAC’s four amino acid substitutions provide a substantially longer and more consistent research window while maintaining the same pulsatile GH release profile. The D-alanine substitution at position 2 specifically targets the primary DPP-4 cleavage site that limits Sermorelin’s in vivo stability, and additional substitutions further extend resistance to enzymatic degradation in biological matrices.

Key cited studies:

• Jetté L et al. (2005) — hGRF(1-29)-Albumin Bioconjugates Activate the GRF Receptor on the Anterior Pituitary in Rats: Identification of CJC-1295 as a Long-Lasting GRF Analog — Endocrinology 146(7):3052–3058. PubMed ID: 15817669. DOI: 10.1210/en.2004-1611
• Teichman SL et al. (2006) — Prolonged Stimulation of GH and IGF-1 Secretion by CJC-1295, a Long-Acting Analog of GHRH, in Healthy Adults — J Clin Endocrinol Metab 91(3):799–805. DOI: 10.1210/jc.2005-1536
• Ionescu M & Frohman LA (2006) — Pulsatile Secretion of GH Persists During Continuous Stimulation by CJC-1295, a Long-Acting GHRH Analog — J Clin Endocrinol Metab 91(12):4792–4797. PubMed ID: 17018654
• Alba M et al. (2006) — Once-Daily Administration of CJC-1295 Normalises Growth in the GHRH Knockout Mouse — Am J Physiol Endocrinol Metab 291(6):E1290–E1294. DOI: 10.1152/ajpendo.00201.2006
• Raun K et al. (1998) — Ipamorelin, the First Selective Growth Hormone Secretagogue — Eur J Endocrinol 139(5):552–561. PubMed ID: 9849822

CJC-1295 Without DAC vs Other GHRH-Class Research Peptides

Feature	CJC-1295 Without DAC (Mod GRF 1-29)	CJC-1295 With DAC	Sermorelin (GRF 1-29)	Tesamorelin
Amino Acid Substitutions	4 (D-Ala², Gln⁸, Ala¹⁵, Leu²⁷)	4 + DAC reactive lysine at C-terminus	None (C-terminal amide only)	N-terminal trans-3-hexenoyl cap
DPP-4 Resistance	High (all 4 substitutions)	High (4 substitutions + albumin protection)	Low (rapid DPP-4 cleavage)	High (N-terminal cap)
Half-Life	~30 minutes	6–8 days	~11–12 minutes	~26–38 minutes
Albumin Binding	No	Yes (covalent, via DAC)	No	No
GH Release Pattern	Physiological pulsatile	Sustained with preserved pulsatility	Physiological pulsatile	Physiological pulsatile
GHRH-R Selectivity	High (no GHS-R1a cross-reactivity)	High	High	High
Somatostatin Feedback	Preserved	Partially modulated	Preserved	Preserved
Best Research Use	Pulsatile GH axis, dual-pathway stack with Ipamorelin	Sustained GH axis elevation studies	Ultra-short pulse reference, FSH/LH biology	VAT/lipid pathway and CV risk research
Dual-Pathway Stack	Yes (primary GHRH component with Ipamorelin)	Yes (sustained GHRH + acute GHRP)	Yes (shortest pulse GHRH reference)	No established stack model

CJC-1295 Without DAC’s unique combination of four stabilising amino acid substitutions, full GHRH receptor selectivity, physiological pulsatile GH release architecture, somatostatin feedback preservation, and ~30-minute half-life makes it the most versatile and broadly applicable pulsatile GHRH-class secretagogue for GH axis research — and the defining GHRH component in the most widely studied dual-receptor GH secretagogue combination in pre-clinical literature.

Quality & Purity Assurance

Every batch of CJC-1295 Without DAC from Peptides Lab UK is:

• >99% pure — HPLC and mass spectrometry verified
• Supplied with a full Certificate of Analysis (COA) on request
• Lyophilised powder for maximum stability and long shelf life
• Manufactured under strict, controlled laboratory conditions
• Consistent batch-to-batch quality for reproducible research results

Buy CJC-1295 Without DAC UK — Product Specifications

Property	Detail
Full Name	CJC-1295 Without DAC / Modified GRF (1-29) / Mod GRF (1-29)
Also Known As	Tetrasubstituted GRF (1-29), Mod GRF 1-29
Sequence	H-Tyr-D-Ala-Asp-Ala-Ile-Phe-Thr-Gln-Ser-Tyr-Arg-Lys-Val-Leu-Ala-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Leu-Ser-Arg-NH₂
Amino Acids	29
Substituted Positions	2 (D-Ala), 8 (Gln), 15 (Ala), 27 (Leu)
Molecular Weight	3,368.7 g/mol
Molecular Formula	C₁₅₂H₂₅₂N₄₄O₄₂
Effective Half-Life	~30 minutes
Purity	>99% (HPLC verified)
Form	Lyophilised powder
Storage	Store dry at -20°C; protect from light
Solubility	Bacteriostatic water, sterile water, or suitable laboratory solvents

CJC-1295 Without DAC Research Applications

CJC-1295 Without DAC (Modified GRF 1-29) peptide UK is supplied strictly for the following in vitro and pre-clinical research uses:

• GHRH receptor binding, Gs/adenylate cyclase activation, and cAMP/PKA signalling pathway studies
• Physiological pulsatile GH secretion modelling and somatotroph biology investigations
• GH and IGF-1 axis regulation and downstream anabolic pathway research
• DPP-4 resistance profiling and GHRH analogue structural pharmacology comparisons
• Somatotroph proliferation, GH mRNA transcription, and pituitary reserve studies
• GH pulsatility architecture — pulse amplitude, frequency, trough levels, and inter-pulse interval modelling
• Somatostatin feedback dynamics and hypothalamic-pituitary somatostatin/GHRH interplay research
• Metabolic pathway investigations — lipid oxidation, glucose homeostasis, and anabolic signalling
• GH axis ageing and somatopause biology — GHRH pulse amplitude decline modelling
• Dual-pathway synergy research as the GHRH component in combination with GHS-R1a agonists (Ipamorelin, GHRP-2, GHRP-6)
• Comparative pulsatile GHRH analogue SAR studies — reference compound for Sermorelin and Tesamorelin comparisons

Why Buy CJC-1295 Without DAC from Peptides Lab UK?

Peptides Lab UK is a trusted UK peptides supplier, providing research-grade compounds verified by independent HPLC testing. When you buy CJC-1295 Without DAC in the UK from us, you receive:

• >99% purity, HPLC and MS verified, third-party tested
• Full COA documentation per batch
• Fast same-day UK dispatch with tracked delivery
• Competitive pricing with bulk research discounts available
• Trusted by researchers across the UK and Europe

Research Disclaimer All products supplied by Peptides Lab UK are intended strictly for in vitro laboratory research and scientific study use only. They are not intended for human consumption, veterinary use, or any medical or therapeutic application. CJC-1295 Without DAC (Modified GRF 1-29) is not a licensed medicine or drug and has not been approved by the MHRA, FDA, or any regulatory authority for use in humans or animals. CJC-1295 Without DAC, as a GHRH analogue, is classified as a prohibited substance under WADA regulations and is not approved for use in sport or competition. All research citations on this page relate to pre-clinical studies and peer-reviewed pharmacological research and do not constitute a claim of safety or therapeutic efficacy. Peptides Lab UK accepts no liability for any misuse of research compounds. By purchasing, you confirm that you are a qualified researcher and that the product will be used solely within a controlled laboratory environment in compliance with all applicable UK laws, regulations, and institutional guidelines.