Increased tumor necrosis factor-α and nitric oxide production by rat macrophages following in vitro stimulation and intravenous administration of the δ-opioid agonist SNC 80

Abstract Opioids alter immune function by binding to opioid receptors on cells of the immune system, or indirectly by acting on receptors within the central nervous system. Mu-selective opioid agonists are generally associated with immunosuppression, whereas δ-opioid receptor-selective agonists are commonly associated with immunopotentiation. We have previously shown that intracerebroventricular administration of the non-peptide δ-opioid receptor agonist (+)-4-((alpha R)-alpha-((2S, 5R)-4-allyl-2, 5-dimethyl-1-piperazinyl)-3-methoxybenzyl)-N, N-diethyl-benzamide (SNC 80) did not alter certain parameters of immunocompetence. In the present study, we studied the in vitro and ex vivo effects of SNC 80 on rat macrophage and lymphocyte functions. We showed that SNC 80 at concentrations of 10 −7 M and 10 −6 M, significantly ( P P