Adenosine receptor activation and nociception

Ahlijanian, 1985, Effects of (−)-N6-(R-phenylisopropyl)-adenosine (PIA) and caffeine on nociception and morphine-induced analgesia, tolerance and dependence in mice, Eur. J. Pharmacol., 112, 171, 10.1016/0014-2999(85)90493-5 Akbar, 1994, A single species of A1 adenosine receptor expressed in chinese hamster ovary cells not only inhibits cAMP accumulation but also stimulates phospholipase C and arachidonate release, Mol. Pharmacol., 45, 1036 Aley, 1997, Multiple receptors involved in peripheral α2, μ and A1 antinociception, tolerance and withdrawal, J. Neurosci., 17, 735, 10.1523/JNEUROSCI.17-02-00735.1997 Aran, 1990, Antinociception produced by interactions between intrathecally administered adenosine agonists and norepinephrine, Brain Res., 513, 255, 10.1016/0006-8993(90)90464-M Aran, 1990, Antinociceptive interactions between intrathecally administered α noradrenergic agonists and 5′-N-ethylcarboxamide adenosine, Brain Res., 519, 287, 10.1016/0006-8993(90)90090-X Belfrage, 1995, Systemic adenosine infusion alleviates spontaneous and stimulus evoked pain in patients with peripheral neuropathic pain, Anesth. Analg., 81, 713 Bertolet, 1993, Absence of adenosine-induced chest pain after total cardiac afferent denervation, Am. J. Cardiol., 72, 483, 10.1016/0002-9149(93)91150-G Bleehen, 1977, Observations on the algogenic actions of adenosine compounds on the human blister base preparation, Pain, 3, 367, 10.1016/0304-3959(77)90066-5 Burke, 1988, Regulation of glutamate and aspartate release from slices of the hippocampal CA1 area: Effects of adenosine and baclofen, J. Neurochem., 51, 1541, 10.1111/j.1471-4159.1988.tb01123.x Burnstock, 1996, Purinergic receptors: Their role in nociception and primary afferent neurotransmission, Curr. Opin. Neurobiol., 6, 526, 10.1016/S0959-4388(96)80060-2 Cahill, 1995, Spinal opioid receptors and adenosine release: Neurochemical and behavioural characterization of opioid subtypes, J. Pharmacol. Exp. Ther., 275, 84 Calignano, 1992, Adenosine release in morphine-induced hypotension in rats, Gen. Pharmac., 23, 7, 10.1016/0306-3623(92)90039-M Castañeda-Hernández, 1994, Potentiation by caffeine of the analgesic effect of aspirin in the pain-induced functional impairment model in the rat, Can. J. Physiol. Pharmacol., 72, 1127, 10.1139/y94-159 Choca, 1987, Identification of A1 and A2 adenosine receptors in the rat spinal cord, J. Pharmacol. Exp. Ther., 242, 905 Choca, 1988, Adenosine A1 and A2 receptors of the substantia gelatinosa are located predominantly on intrinsic neurons: An autoradiographic study, J. Pharmacol. Exp. Ther., 247, 757 Collier, 1966, Antagonism by aspirin and fenamates of bronchoconstriction and nociception induced by adenosine 5′-triphosphate, Nature, 5060, 411, 10.1038/212411a0 Contreras, 1990, Effects of some adenosine analogs on morphine-induced analgesia and tolerance, Gen. Pharmac., 21, 763, 10.1016/0306-3623(90)91031-L Corradetti, 1984, Adenosine decreases aspartate and glutamate release from rat hippocampal slices, Eur. J. Pharmacol., 104, 19, 10.1016/0014-2999(84)90364-9 Crawley, 1981, Behavioral characterization of two long-lasting adenosine analogs: Sedative properties and interaction with diazepam, Life Sci., 29, 2623, 10.1016/0024-3205(81)90636-6 Crea, F., Galassi, A.R., Kaski, J.C., Pupita, G., El Tamimi, H., Davies, G.J., Maseri, A., 1989. Effect of theophylline on exercise-induced myocardial ischaemia. Lancet, 683–686. Crea, 1990, Role of adenosine in pathogenesis of anginal pain, Circulation, 81, 164, 10.1161/01.CIR.81.1.164 Crea, 1992, Relation between stimulation site of cardiac afferent nerves by adenosine and distribution of cardiac pain: Results of a study in patients with stable angina, J. Am. Coll. Cardiol., 20, 1498, 10.1016/0735-1097(92)90442-P Cronstein, 1994, Adenosine, an endogenous anti-inflammatory agent, J. Appl. Physiol., 76, 5, 10.1152/jappl.1994.76.1.5 Cronstein, 1995, A novel approach to the development of anti-inflammatory agents: Adenosine release at inflamed sites, J. Invest. Med., 43, 50 Cronstein, 1995, The anti-inflammatory effects of an adenosine kinase inhibitor are mediated by adenosine, Arth. Rheum., 38, 1040, 10.1002/art.1780380804 Cui, 1997, Adenosine receptor activation suppresses hypersensitivity and potentiates spinal cord stimulation in mononeuropathic rats, Neurosci. Lett., 223, 173, 10.1016/S0304-3940(97)13435-8 DeLander, 1986, Spinal adenosine modulates descending antinociceptive pathways stimulated by morphine, J. Pharmacol. Exp. Ther., 239, 88 DeLander, 1987, Involvement of A2 adenosine receptors in spinal mechanisms of antinociception, Eur. J. Pharmacol., 139, 215, 10.1016/0014-2999(87)90254-8 DeLander, 1994, Antinociception induced by intrathecal coadministration of selective adenosine receptor and selective opioid receptor agonists, J. Pharmacol. Exp. Ther., 268, 943 DeLander, 1988, Behavior induced by putative nociceptive neurotransmitters is inhibited by adenosine or adenosine analogs coadministered intrathecally, J. Pharmacol. Exp. Ther., 246, 565 DeLander, 1989, Morphine (intracerebroventricular) activates spinal systems to inhibit behavior induced by putative pain neurotransmitters, J. Pharmacol. Exp. Ther., 251, 1090 DeLander, 1991, Descending systems activated by morphine (ICV) inhibit kainic acid (IT)-induced behavior, Pharmacol. Biochem. Behav., 39, 155, 10.1016/0091-3057(91)90414-W De Montis, 1992, Decreased adenosine A2 receptor function in morphine dependent rats, Pharmacol. Res., 25 (Suppl. 2), 232, 10.1016/1043-6618(92)90378-O Dibner-Dunlap, 1993, Activation of cardiac sympathetic afferents: Effects of exogenous adenosine and adenosine analogues, Am. J. Physiol., 265, H395 Doak, 1995, Complex role of peripheral adenosine in the genesis of the response to subcutaneous formalin in the rat, Eur. J. Pharmacol., 281, 311, 10.1016/0014-2999(95)00257-L Doi, 1987, Spinal antinociceptive effects of adenosine compounds in mice, Eur. J. Pharmacol., 137, 227, 10.1016/0014-2999(87)90226-3 Dray, 1995, Inflammatory mediators of pain, Br. J. Anaesth., 75, 125, 10.1093/bja/75.2.125 Ekblom, 1995, Adenosine increases the cutaneous heat pain threshold in healthy volunteers, Acta Anaesthesiol. Scand., 39, 717, 10.1111/j.1399-6576.1995.tb04158.x Eschalier, 1994, Why are antidepressants effective as pain relief?, CNS Drugs, 2, 261, 10.2165/00023210-199402040-00002 Fastbom, 1990, Antinociceptive effects and spinal distribution of two adenosine receptor agonists after intrathecal administration, Pharmacol. Toxicol., 66, 69, 10.1111/j.1600-0773.1990.tb00706.x Forbes, 1991, Effect of caffeine on ibuprofen analgesia in postoperative oral surgery pain, Clin. Pharm. Ther., 49, 674, 10.1038/clpt.1991.85 Fredholm, 1995, Adenosine, adenosine receptors and the actions of caffeine, Pharmacol. Toxicol., 76, 93, 10.1111/j.1600-0773.1995.tb00111.x Fredholm, 1978, Morphine increases depolarization induced purine release from rat cortical slices, Acta Physiol. Scand., 104, 502, 10.1111/j.1748-1716.1978.tb06308.x Fredholm, 1994, Nomenclature and classification of purinoceptors, Pharmacol. Rev., 46, 143 Gaspardone, 1994, Substance P potentiates the algogenic effects of intraarterial infusion of adenosine, J. Am. Coll. Cardiol., 24, 477, 10.1016/0735-1097(94)90306-9 Gaspardone, 1995, Muscular and cardiac adenosine-induced pain is mediated by A1 receptors, J. Am. Coll. Cardiol., 25, 251, 10.1016/0735-1097(94)00352-Q Geiger, 1984, Characterization and localization of adenosine receptors in rat spinal cord, J. Neurosci., 4, 2303, 10.1523/JNEUROSCI.04-09-02303.1984 Germany, 1990, Influence of adenosine analogs on morphine tolerance and dependence in mice, Cell. Mol. Biol., 36, 409 Ghelardini, 1997, Caffeine induces central cholinergic analgesia, Naunyn-Schmiedeberg's Arch. Pharmacol., 356, 590, 10.1007/PL00005094 Goodman, 1982, Autoradiographic localization of adenosine receptors in rat brain using [3H]cyclohexyladenosine, J. Neurosci., 2, 1230, 10.1523/JNEUROSCI.02-09-01230.1982 Gourley, 1973, Antagonism of morphine analgesia by adenine, adenosine, and adenine nucleotides, Proc. Soc. Exp. Biol. Med., 144, 774, 10.3181/00379727-144-37680 Granados-Soto, 1993, Characterization of the analgesic effects of paracetamol and caffeine combinations in the pain-induced functional impairment model in the rat, J. Pharm. Pharmacol., 45, 627, 10.1111/j.2042-7158.1993.tb05666.x Guieu, 1996, Adenosine and neuropathic pain, Pain, 68, 271, 10.1016/S0304-3959(96)03214-9 Herrick-Davis, 1989, Evaluation of adenosine agonists as potential analgesics, Eur. J. Pharmacol., 162, 365, 10.1016/0014-2999(89)90301-4 Hill, 1990, Distribution, properties and functional characteristics of three classes of histamine receptor, Pharmacol. Rev., 42, 45 Ho, 1973, Cyclic adenosine monophosphate antagonism of morphine analgesia, J. Pharmacol. Exp. Ther., 185, 336 Holmgren, 1986, Characterization of the antinociceptive effects of some adenosine analogues in the rat, Naunyn-Schmiedebergs Arch. Pharmacol., 334, 290, 10.1007/BF00508784 Hoyer, 1994, International union of pharmacology classification of receptors for 5-hydroxytryptamine (serotonin), Pharmacol. Rev., 46, 157 Huang, 1995, Ventricular sensory neurons in canine dorsal root ganglia: Effects of adenosine and substance P, Am. J. Physiol., R318 Hunskaar, 1986, Intrathecal injection of capsaicin can be used as a behavioural nociceptive test in mice, Neuropharmacology, 25, 1149, 10.1016/0028-3908(86)90163-2 Jonzon, 1989, Theophylline decreases pain in the ischaemic forearm test, Cardiovasc. Res., 9, 807, 10.1093/cvr/23.9.807 Jurna, 1984, Cyclic nucleotides and aminophylline produce different effects on nociceptive motor and sensory responses in the rat spinal cord, Naunyn-Schmiedebergs Arch. Pharmacol., 327, 23, 10.1007/BF00504987 Kaplan, 1997, Up-regulation of adenosine transporter-binding sites in striatum and hypothalamus of opiate tolerant mice, Brain Res., 763, 215, 10.1016/S0006-8993(97)00413-7 Kaplan, 1994, Alterations of adenosine A1 receptors in morphine dependence, Brain Res., 657, 347, 10.1016/0006-8993(94)90990-3 Karlsten, 1995, An A1-selective adenosine agonist abolishes allodynia elicited by vibration and touch after intrathecal injection, Anesth. Analg., 50, 844 Karlsten, 1990, Effects of intrathecal injection of the adenosine receptor agonists R-phenylisopropyl-adenosine and N-ethylcarboxamide-adenosine on nociception and motor function in the rat, Anesth. Analg., 71, 60, 10.1213/00000539-199007000-00010 Karlsten, 1991, The antinociceptive effect of intrathecally administered adenosine analogs in mice correlates with the affinity for the A1-adenosine receptor, Neurosci. Lett., 121, 267, 10.1016/0304-3940(91)90701-T Karlsten, 1992, Local antinociceptive and hyperalgesic effects in the formalin test after peripheral administration of adenosine analogues in mice, Pharmacol. Toxicol., 70, 434, 10.1111/j.1600-0773.1992.tb00503.x Keele, C.A., Armstrong, D., 1964. Substances Producing Pain and Itch. Williams and Wilkins, Baltimore, MD, pp. 124–151. Keil, 1992, Spinally-mediated antinociception is induced in mice by an adenosine kinase-, but not by an adenosine deaminase-inhibitor, Life Sci., 51, 171, 10.1016/0024-3205(92)90566-8 Keil, 1994, Adenosine kinase and adenosine deaminase inhibition modulate spinal adenosine- and opioid agonist-induced antinociception in mice, Eur. J. Pharmacol., 271, 37, 10.1016/0014-2999(94)90262-3 Keil, 1996, Altered sensory behaviours in mice following manipulation of endogenous spinal adenosine neurotransmission, Eur. J. Pharmacol., 312, 7, 10.1016/0014-2999(96)00444-X Khasar, 1995, Mu-opioid agonist enhancement of prostaglandin-induced hyperalgesia in the rat: A G-protein βγ subunit-mediated effect?, Neuroscience, 67, 189, 10.1016/0306-4522(94)00632-F Lagerqvist, 1992, Adenosine induced chest pain: A comparison between intracoronary bolus injection and steady state infusion, Cardiovasc. Res., 26, 810, 10.1093/cvr/26.8.810 Laska, 1984, Caffeine as an analgesic adjuvant, J. Am. Med. Assoc., 251, 1711, 10.1001/jama.251.13.1711 Lee, 1996, Pharmacology of the spinal adenosine receptor which mediates the antiallodynic action of intrathecal adenosine agonists, J. Pharmacol. Exp. Ther., 277, 1642 Levine, J., Taiwo, Y., 1994. Inflammatory pain. In: Wall, P.D., Melzack, R. (Eds.), Textbook of Pain, 3rd ed. Churchill Livingstone, London, pp. 45–56. Li, 1994, Adenosine inhibition of synaptic transmission in the substantia gelatinose, J. Neurophysiol., 72, 1611, 10.1152/jn.1994.72.4.1611 López-Muñoz, 1996, Effect of caffeine coadministration and of nitric oxide synthesis inhibition on the antinociceptive action of ketorolac, Eur. J. Pharmacol., 308, 275, 10.1016/0014-2999(96)00320-2 Lui, 1997, Involvement of spinal adenosine A1 and A2 receptors in fentanyl-induced muscular rigidity in the rat, Neurosci. Lett., 224, 189, 10.1016/S0304-3940(97)00160-2 MacDonald, 1986, Adenosine agonists reduce voltage-dependent calcium conductance of mouse sensory neurons in cell culture, J. Physiol., 370, 75, 10.1113/jphysiol.1986.sp015923 Malec, 1988, The effect of methylxanthines on morphine analgesia in mice and rats, Pol. J. Pharmacol. Pharm., 40, 223 Malec, 1990, The effect of adenosine receptor agonists on analgesic effects of morphine, Pol. J. Pharmacol. Pharm., 42, 1 Malmberg, 1993, Pharmacology of the spinal action of ketorolac, morphine, ST-91, U50488H and l-PIA on the formalin test and an isobolographic analysis of the NSAID interaction, Anesthesiology, 79, 270, 10.1097/00000542-199308000-00012 Marchand, 1995, Effects of caffeine on analgesia from transcutaneous electrical nerve stimulation, N. Engl. J. Med., 333, 325, 10.1056/NEJM199508033330521 Michalska, 1993, Agonists and antagonists of adenosine receptors and morphine withdrawal syndrome in rats, Pol. J. Pharmacol., 45, 1 Minami, 1992, Allodynia evoked by intrathecal administration of prostaglandin F2α to conscious mice, Pain, 50, 223, 10.1016/0304-3959(92)90166-9 Misra, 1985, Potentiation of morphine analgesia by caffeine, Br. J. Pharmacol., 84, 789, 10.1111/j.1476-5381.1985.tb17372.x Möser, 1989, Turnover of adenosine in plasma of human and dog blood, Am. J. Physiol., 256 (Cell Physiol. 25), C799, 10.1152/ajpcell.1989.256.4.C799 Nakamura, 1997, Characterization of adenosine receptors mediating spinal sensory transmission related to nociceptive information in the rat, Anesthesiology, 87, 577, 10.1097/00000542-199709000-00018 Ninkovic, 1982, Localization of opiate and histamine H1-receptors in the primate sensory ganglia and spinal cord, Brain Res., 241, 197, 10.1016/0006-8993(82)91056-3 Ongini, 1996, Pharmacology of adenosine A2A receptors, Trends Pharmacol. Sci., 17, 364, 10.1016/S0165-6147(96)80010-1 Pappagallo, 1993, Analgesic effect of bamiphylline on pain induced by intradermal injection of adenosine, Pain, 53, 199, 10.1016/0304-3959(93)90081-Y Pardridge, 1994, Blood–brain barrier transport and brain metabolism of adenosine and adenosine analogs, J. Pharmacol. Exp. Ther., 268, 14 Person, 1985, Morphine–caffeine analgesic interaction in rats, Anesth. Analg., 64, 851, 10.1213/00000539-198509000-00002 Phillis, 1984, Potentiation of the action of adenosine on cerebral cortical neurones by the tricyclic antidepressants, Br. J. Pharmacol., 83, 567, 10.1111/j.1476-5381.1984.tb16521.x Phillis, 1982, The effect of various centrally active drugs on adenosine uptake by the central nervous system, Comp. Biochem. Physiol., 72C, 179 Pierce, 1996, 5-Hydroxytryptamine receptor subtype messenger RNAs in rat peripheral sensory and sympathetic ganglia: A polymerase chain reaction study, Neuroscience, 70, 553, 10.1016/0306-4522(95)00329-0 Poon, 1995, Antinociception by adenosine analogs and an adenosine kinase inhibitor: Dependence on formalin concentration, Eur. J. Pharmacol., 286, 177, 10.1016/0014-2999(95)00444-P Poon, A., Sawynok, J., 1997. Antinociception by adenosine analogs and inhibitors of adenosine metabolism in an inflammatory thermal hyperalgesia model in the rat. Pain. In press. Portenoy, 1993, Drug therapy for neuropathic pain, Drug Ther., 23, 41 Post, 1984, Antinociceptive effects in mice after intrathecal injection of 5′-N-ethylcarboxamide adenosine, Neurosci. Lett., 51, 325, 10.1016/0304-3940(84)90397-5 Ramkumar, 1993, The A3 adenosine receptor is the unique adenosine receptor which facilitates release of allergic mediators in mast cells, J. Biol. Chem., 268, 16887, 10.1016/S0021-9258(19)85277-8 Reeve, 1995, The roles of spinal adenosine receptors in the control of acute and more persistent nociceptive responses of dorsal horn neurones in the anaesthetized rat, Br. J. Pharmacol., 116, 2221, 10.1111/j.1476-5381.1995.tb15057.x Rosengren, 1995, Anti-inflammatory effects of an adenosine kinase inhibitor. Decreased neutrophil accumulation and vascular leakage, J. Immunol., 154, 5444, 10.4049/jimmunol.154.10.5444 Salter, 1987, Evidence that adenosine mediates the depression of spinal dorsal horn neurons induced by peripheral vibration in the cat, Neuroscience, 22, 631, 10.1016/0306-4522(87)90359-9 Salter, 1993, Physiological roles for adenosine and ATP in synaptic transmission in the spinal dorsal horn, Prog. Neurobiol., 41, 125, 10.1016/0301-0082(93)90006-E Santicioli, 1993, Adenosine A1 receptors mediate the presynaptic inhibition of calcitonin gene-related peptide release by adenosine in the rat spinal cord, Eur. J. Pharmacol., 231, 139, 10.1016/0014-2999(93)90695-E Sawynok, J., 1997. Purines and nociception. In: Jacobson, K.A., Jarvis, M.F. (Eds.), Purinergic Approaches in Experimental Therapeutics. Wiley and Sons, New York, pp. 495–513. Sawynok, 1988, Role of G-proteins and adenylate cyclase in antinociception produced by intrathecal purines, Eur. J. Pharmacol., 156, 25, 10.1016/0014-2999(88)90143-4 Sawynok, 1996, Neurotoxin-induced lesions to central serotonergic, noradrenergic and dopaminergic systems modify caffeine-induced antinociception in the formalin test and locomotor stimulation in rats, J. Pharmacol. Exp. Ther., 277, 646 Sawynok, 1993, Caffeine as an analgesic adjuvant: A review of pharmacology and mechanisms of action, Pharmacol. Rev., 45, 43 Sawynok, 1986, Classification of adenosine receptors mediating antinociception in the rat spinal cord, Br. J. Pharmacol., 88, 923, 10.1111/j.1476-5381.1986.tb16267.x Sawynok, 1991, 8-Phenyltheophylline reverses the antinociceptive action of morphine in the periaqueductal gray, Neuropharmacology, 30, 871, 10.1016/0028-3908(91)90121-Q Sawynok, 1995, Caffeine antinociception in the rat hot-plate and formalin tests and locomotor stimulation: Involvement of noradrenergic mechanisms, Pain, 61, 203, 10.1016/0304-3959(94)00169-F Sawynok, 1998, Peripheral antinociceptive effect of an adenosine kinase inhibitor, with augmentation by an adenosine deaminase inhibitor, in the rat formalin test, Pain, 74, 75, 10.1016/S0304-3959(97)00153-X Sawynok, 1997, Adenosine A3 receptor activation produces nociceptive behaviour and edema by release of histamine and 5-hydroxytryptamine, Eur. J. Pharmacol., 333, 1, 10.1016/S0014-2999(97)01110-2 Segerdahl, 1994, The influence of adenosine, ketamine and morphine on experimentally induced ischemic pain in healthy volunteers, Anesth. Analg., 79, 787, 10.1213/00000539-199410000-00029 Segerdahl, 1995, Peroperative adenosine infusion reduces the requirements for isoflurane and postoperative analgesics, Anesth. Analg., 80, 1145 Segerdahl, 1995, Systemic adenosine attenuates touch evoked allodynia induced by mustard oil in humans, Neuroreport, 6, 753, 10.1097/00001756-199503270-00012 Segerdahl, 1996, Peroperative adenosine infusion reduces isoflurane concentrations during general anesthesia for shoulder surgery, Acta Anaesth. Scand., 40, 792, 10.1111/j.1399-6576.1996.tb04534.x Sierralta, 1995, Interaction of opioids with antidepressant-induced antinociception, Psychopharmacology, 122, 374, 10.1007/BF02246269 Sjölund, 1996, Intrathecal and systemic R-phenylisopropyladenosine reduces scratching behaviour in a rat mononeuropathy model, Neuroreport, 7, 1856, 10.1097/00001756-199607290-00034 Sjölund, 1997, Intrathecal adenosine analog administration reduces substance P in cerebrospinal fluid along with behavioral effects that suggest antinociception in rats, Anesth. Analg., 85, 627, 10.1213/00000539-199709000-00025 Smart, 1996, The stimulatory effects of opioids and their possible role in the development of tolerance, Trends Pharmacol. Sci., 17, 264, 10.1016/0165-6147(96)10023-7 Sollevi, 1995, Systemic adenosine infusion: A new treatment modality to alleviate neuropathic pain, Pain, 61, 155, 10.1016/0304-3959(94)00187-J Sosnowski, 1989, Role of spinal adenosine receptors in modulating the hyperesthesia produced by spinal glycine receptor antagonism, Anesth. Analg., 69, 587, 10.1213/00000539-198911000-00006 Sosnowski, 1989, Assessment of the role of A1/A2 adenosine receptors mediating the purine antinociception, motor and autonomic function in the rat spinal cord, J. Pharmacol. Exp. Ther., 250, 915 Stone, 1981, The effects of morphine and methionine–enkephalin on the release of purines from cerebral cortex slices of rats and mice, Br. J. Pharmacol., 74, 171, 10.1111/j.1476-5381.1981.tb09970.x Stone, 1979, Antidepressant drugs potentiate suppression by adenosine of neuronal firing in rat cerebral cortex, Neurosci. Lett., 11, 93, 10.1016/0304-3940(79)90062-4 Suh, 1997, Differential effects of adenosine receptor antagonists injected intrathecally on antinociception induced by morphine and β-endorphin administered intracerebroventricularly in the mouse, Neuropeptides, 31, 339, 10.1016/S0143-4179(97)90069-X Sweeney, 1987, Involvement of adenosine in the spinal antinociceptive effects of morphine and noradrenaline, J. Pharmacol. Exp. Ther., 243, 657 Sweeney, 1989, Morphine, capsaicin and K+ release purines from capsaicin-sensitive primary afferent nerve terminals in the spinal cord, J. Pharmacol. Exp. Ther., 248, 447 Sweeney, 1990, 5-Hydroxytryptamine releases adenosine and cyclic AMP from primary afferent nerve terminals in the spinal cord in vivo, Brain Res., 528, 55, 10.1016/0006-8993(90)90194-G Sweeney, 1991, Intracerebroventricular morphine releases adenosine and adenosine 3′, 5′-cyclic monophosphate from the spinal cord via a serotonergic mechanism, J. Pharmacol. Exp. Ther., 259, 1013 Sweeney, 1993, Morphine-evoked release of adenosine from the spinal cord occurs via a nucleoside carrier with differential sensitivity to dipyridamole and nitrobenzylthioinosine, Brain Res., 614, 301, 10.1016/0006-8993(93)91048-W Sylvén, 1986, Angina pectoris-like pain provoked by intravenous adenosine in healthy volunteers, Br. Med. J., 293, 227, 10.1136/bmj.293.6541.227 Sylvén, 1988, Provocation of chest pain in patients with coronary insufficiency using the vasodilator adenosine, Eur. Heart J., 9 (Suppl. N), 6, 10.1093/eurheartj/9.suppl_N.6 Sylvén, 1988, Adenosine injection into the brachial artery produces ischemia like pain or discomfort in the forearm, Cardiovasc. Res., 22, 674, 10.1093/cvr/22.9.674 Sylvén, 1990, Nicotine enhances angina pectoris-like pain and atrioventricular blockade provoked by intravenous bolus of adenosine in healthy volunteers, J. Cardiovasc. Pharmacol., 16, 962, 10.1097/00005344-199012000-00015 Taiwo, 1990, Direct cutaneous hyperalgesia induced by adenosine, Neuroscience, 38, 757, 10.1016/0306-4522(90)90068-F Taiwo, 1991, Further confirmation of the role of adenyl cyclase and of cAMP-dependent protein kinase in primary afferent hyperalgesia, Neuroscience, 44, 131, 10.1016/0306-4522(91)90255-M Tao, 1992, Chronic morphine treatment causes down-regulation of spinal adenosine A1 receptors in rats, Eur. J. Pharmacol., 215, 301, 10.1016/0014-2999(92)90044-5 Tao, 1995, Chronic intracerebroventricular administration of morphine down-regulates spinal adenosine A1 receptors in rats, Eur. J. Pharmacol., 278, 233, 10.1016/0014-2999(95)00124-4 Vapaatalo, 1975, Stereospecificity in some central and circulatory effects of phenylisopropyl-adenosine (PIA), Arzneim. Forsch., 25, 407 Watt, 1987, Reproduction of epigastric pain of duodenal ulceration by adenosine, Br. Med. J., 294, 10, 10.1136/bmj.294.6563.10 White, 1995, The role of adenosine in the hypotensive actions of morphine, Eur. J. Pharmacol., 286, 315, 10.1016/0014-2999(95)00598-X Wu, 1982, Morphine enhances the release of 3H-purines from rat brain cerebral cortical prisms, Pharmacol. Biochem. Behav., 17, 749, 10.1016/0091-3057(82)90357-4 Yamamoto, 1991, Spinal pharmacology of thermal hyperesthesia induced by incomplete ligation of sciatic nerve, Anesthesiology, 75, 817, 10.1097/00000542-199111000-00014 Yang, 1994, Morphine and norepinephrine-induced antinociception at the spinal level is mediated by adenosine, NeuroReport, 5, 1441, 10.1097/00001756-199407000-00009 Yang, 1995, Adenosine and opiate-like substances mediates antinociception at the spinal cord, Brain Res., 673, 170, 10.1016/0006-8993(94)01464-S Yarbrough, 1981, In vivo behavioral assessment of central nervous system purinergic receptors, Eur. J. Pharmacol., 76, 137, 10.1016/0014-2999(81)90495-7