Thienorphine is an oripavine with long-lasting antinociceptive effects in mice that are thought to be mediated by mu-opioid receptors. This study examined the receptor binding of thienorphine in cell membrane homogenates and its behavioral effects in rhesus monkeys (Macaca mulatta). Affinity and potency were determined using radioligand displacement and stimulation of guanosine 5'-O-(3-[35S]thi...

The dermorphin-derived peptide [Dmt1]DALDA (H-Dmt-d-Arg-Phe-Lys-NH2; Dmt, 2',6'-dimethyltyrosine) labels mu-opioid receptors with high affinity and selectivity in receptor binding assays. In previous studies, [Dmt1]DALDA displayed a mechanism of action distinct from that of morphine, as evidenced by its insensitivity to antisense probes reducing morphine analgesia and incomplete cross tolerance...

IN the past decade narcotic analgesics have been widely used to supplement thiopentone-nitrous oxide-oxygen anaesthesia. Pethidine (Neff, Mayer and Perales, 1947) and alphaprodine (Siker, Foldes, Pahk and Swerdlow, 1954) have been most frequently employed, but many other narcotics, e.g. levorphanol (Brotman, Cullen and Wilkins, 1950) and anileridine (Riffin et al., 1958) have also been used. In...

Pethidine is indicated for the treatment of moderate to severe pain, and is delivered as its hydrochloride salt in tablets, as a syrup, or by intramuscular or intravenous injection. For much of the 20th century, pethidine was the opioid of choice for many physicians; in 1983 60% of doctors prescribed it for acute pain and 22% for chronic severe pain. Compared to morphine, pethidine was supposed...

A nonisotopic, immunoelectrophoretic technique was used to analyze the characteristics of opioid-evoked activation of Gi2/ G(x/z) transducer proteins of mouse periaqueductal gray matter membranes. In the presence of picomolar concentrations of guanosine 5'-O-(3-thiotriphosphate), the opioid agonists promoted concentration-dependent increases of immunoreactivity associated with free Gi2alpha and...

Substantial evidence has been accumulated which suggests that opioid delta receptors may be distinguished on the basis of their involvement in the modulation (i.e., increase or decrease in potency) of mu-mediated antinociception. On this basis, it has been hypothesized that some opioid delta receptors exist within a functional complex with mu receptors (delta complexed (delta cx) receptors) whi...

The heritability of nociception and antinociception has been well established in the mouse. The pharmacogenetics of morphine analgesia are fairly well characterized, but far less is known about other analgesics. The purpose of this work was to begin the systematic genetic study of non-mu-opioid analgesics. We tested mice of 12 inbred mouse strains for baseline nociceptive sensitivity (49 degree...

In C6 glial cells stably expressing rat mu-opioid receptor, opioid agonist activation is negatively coupled to adenylyl cyclase through pertussis toxin-sensitive G proteins. In membranes, [D-Ala2, N-MePhe4,Gly-ol5]enkephalin (DAMGO) increases guanosine-5'-O-(3-[35S]thio)triphosphate (GTP[gamma-35S]) binding by 367% with an EC50 value of 28 nM. Prolonged exposure to agonists induced desensitizat...

Pethidine is indicated for the treatment of moderate to severe pain, and is delivered as its hydrochloride salt in tablets, as a syrup, or by intramuscular or intravenous injection. For much of the 20th century, pethidine was the opioid of choice for many physicians; in 1983 60% of doctors prescribed it for acute pain and 22% for chronic severe pain. Compared to morphine, pethidine was supposed...

The purpose of this study was to evaluate the effects of a morphine-conjugate vaccine (M-KLH) on the acquisition, maintenance, and reinstatement of heroin self-administration (HSA) in rats, and on heroin and metabolite distribution during heroin administration that approximated the self-administered dosing rate. Vaccination with M-KLH blocked heroin-primed reinstatement of heroin responding. Va...