Endomorphins: Promising Endogenous Opioid Peptides for the Development of Novel Analgesics.

Endomorphins: Promising Endogenous Opioid Peptides for the Development of Novel Analgesics. Neurosignals. 2017 Nov 13;25(1):98-116 Authors: Gu ZH, Wang B, Kou ZZ, Bai Y, Chen T, Dong YL, Li H, Li YQ Abstract Endomorphin-1 (EM1) and endomorphin-2 (EM2) are two endogenous ligands that belong to the opioid peptide family and have the highest affinity and selectivity for the ยต-opioid receptor (MOR). The neuroanatomical distribution, ultrastructural features and neural circuitry of EM-containing neuronal structures have been morphologically demonstrated. In addition, the modulation effects of the EMs in different areas reflect their potential endogenous roles in many major physiological processes, including their remarkable roles in the transmission and modulation of noxious information. The distinguished antinociceptive property of the EMs in acute and chronic pain, including neuropathic pain, cancer pain and inflammatory pain, has been revealed and investigated for therapeutic purposes. However, EMs exert adverse effects in the gastrointestinal, urinary, cardiovascular, and respiratory systems, which impede the development of EMs as new analgesics. Numerous studies have synthesized and investigated EM analogues and demonstrated that these EM derivatives had improved pharmacological properties, supporting their therapeutic perspectives. In the present review, the results of previous studies, particularly morphological and pharmacologica...
Source: Neuro-Signals - Category: Neurology Authors: Tags: Neurosignals Source Type: research