| Bioactivity | [Leu5]-Enkephalin, amide is a δ opioid receptor agonist. | ||||||
| Target | δ opioid receptor | ||||||
| Invitro | [Leu5]-Enkephalin causes concentration-dependent, reversible inhibition of pelvic nerve-evoked contractions, with an IC50 value of 2.1 nM[2]. | ||||||
| In Vivo | Levels of [Leu5]-Enkephalin are significantly increased in the nucleus raphe magnus (NRM) of rats 2 weeks after the injection of complete Freund's adjuvant (CFA) (1.02±0.2 pmol/mg protein) as compared with saline-treated rats (0.49±0.04 pmol/mg protein; p<0.01). Tissue levels of [Leu5]-Enkephalin are uniformly increased in the caudal ventrolateral periaqueductal gray (PAG) 4 hr (1.15±0.25 pmol/mg protein), 4 d (1.16±0.18 pmol/mg protein), and 2 weeks (1.18±0.17 pmol/mg protein) after the injection of CFA as compared with saline-treated rats (0.55±0.03 pmol/mg protein; p<0.05, all times). A smaller increase in the levels of [Leu5]-Enkephalin occurred in the rostral aspect of the ventrolateral PAG at all time points. Finally, levels of [Leu5]-Enkephalin are also increased in the contralateral microcellular tegmental nucleus 4 d after the injection of CFA (0.53±0.04 pmol/mg protein) compared with levels in saline-treated rats (0.38±0.02 pmol/mg protein; p<0.05)[1]. | ||||||
| Name | [Leu5]-Enkephalin, amide | ||||||
| CAS | 60117-24-0 | ||||||
| Sequence | Tyr-Gly-Gly-Phe-Leu-NH2 | ||||||
| Shortening | YGGFL-NH2 | ||||||
| Formula | C28H38N6O6 | ||||||
| Molar Mass | 554.64 | ||||||
| Appearance | Solid | ||||||
| Transport | Room temperature in continental US; may vary elsewhere. | ||||||
| Storage | Sealed storage, away from moisture and light
*In solvent : -80°C, 6 months; -20°C, 1 month (sealed storage, away from moisture and light) |
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| Reference | [1]. Hurley RW, et al. Contribution of endogenous enkephalins to the enhanced analgesic effects of supraspinal mu opioid receptor agonists after inflammatory injury. J Neurosci. 2001 Apr 1;21(7):2536-45. [2]. Kennedy C, et al. [Met5]enkephalin acts via delta-opioid receptors to inhibit pelvic nerve-evoked contractions of cat distal colon. Br J Pharmacol. 1987 Oct;92(2):291-8. |