Overview
MK-677, also known as Ibutamoren or Nutrobal, is a potent, orally active, non-peptide growth hormone secretagogue (GHS) that mimics the action of ghrelin by selectively binding to the growth hormone secretagogue receptor (GHSR-1a). Originally developed by Merck & Co., MK-677 stimulates pulsatile growth hormone (GH) release and elevates insulin-like growth factor 1 (IGF-1) levels without affecting cortisol or prolactin at standard research doses. Unlike injectable GH-releasing peptides, MK-677 is orally bioavailable and has a half-life of approximately 24 hours, enabling once-daily research dosing. FenaLife supplies MK-677 for laboratory research use only.
Research Background
MK-677 has been studied in clinical trials for sarcopenia, growth hormone deficiency, bone density improvement, and metabolic conditions. A landmark 2-year randomized controlled trial in elderly adults demonstrated sustained increases in GH and IGF-1, improved lean body mass, and increased bone mineral density without significant adverse effects on glucose metabolism at lower doses. More recent research has explored MK-677 in the context of obesity pharmacology and cachexia prevention, particularly in combination with GLP-1 receptor agonists where muscle preservation is a concern.
Studied Mechanisms
MK-677 activates GHSR-1a receptors in the hypothalamus and pituitary, producing a dual effect: stimulating GHRH release from the hypothalamus while simultaneously suppressing somatostatin tone. This results in amplified pulsatile GH secretion from the anterior pituitary. The downstream IGF-1 elevation drives anabolic effects in muscle and bone. Unlike exogenous GH administration, MK-677 preserves the natural pulsatile GH release pattern, which is considered important for maintaining receptor sensitivity and minimizing desensitization in long-term research protocols.
Molecular Profile
Type: Non-peptide small molecule (GH secretagogue). Target: GHSR-1a (ghrelin receptor). Molecular formula: C27H36N4O5S. Molecular weight: 528.66 g/mol. Oral bioavailability: ~60-70%. Half-life: ~24 hours. Also known as: Ibutamoren, Nutrobal, L-163,191. Purity: ≥98% by HPLC.
Storage and Handling
Store MK-677 at room temperature or refrigerated (4°C) in a dry environment, away from light and moisture. MK-677 is stable at room temperature for short periods due to its small-molecule structure. For long-term storage, refrigeration is preferred. Keep sealed until use.
Research Use Only
For laboratory research purposes only. Not for human or veterinary use. Certificate of Analysis available per batch.
🔬 Research Compounds Referenced: BAC Water 10ml