Orphanin FQNociceptin

Recently, an opioid-related peptide has been identified termed orphanin FQ or nociceptin (OFQ/N). OFQ/N is the endogenous ligand for the fourth member of the opioid receptor gene family, ORL-1. Although it has some similarities to the traditional opioid peptides, it also has many significant differences. Like dynorphin A, OFQ/N is a heptadecapeptide (Table I) and its first four amino acids (Phe-Gly-Gly-Phe-) are similar to those of the traditional opioid peptides (Tyr-Gly-Gly-Phe-). However, OFQ/N has very poor affinity for the traditional opioid receptors, whereas the opioid pep-tides show no appreciable affinity for the ORL-1 receptor. Functionally, OFQ/N is also quite distinct from the opioid peptides. Although high doses of OFQ/N can elicit analgesia, low doses given suprasp-inally functionally reverse the opioid analgesia. The precursor for OFQ/N has been cloned, and it too contains additional putative neuropeptides, including nocistatin and OFQ2 (Fig. 2D).

Breaking Bulimia

Breaking Bulimia

We have all been there: turning to the refrigerator if feeling lonely or bored or indulging in seconds or thirds if strained. But if you suffer from bulimia, the from time to time urge to overeat is more like an obsession.

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