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Endogenous cannabinoids and appetite

Published online by Cambridge University Press:  14 December 2007

Tim C. Kirkham  and
Claire M. Williams
Tim C. Kirkham*
Affiliation:
Department of Psychology, University of Reading, Whiteknights, PO Box 238, Reading RG6 6AL, UK
Claire M. Williams
Affiliation:
Department of Psychology, University of Reading, Whiteknights, PO Box 238, Reading RG6 6AL, UK
*
*Corresponding author: Dr Tim C. Kirkham, fax +44 118 931 6715, email: t.c.kirkham@reading.ac.uk
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Abstract

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Since pre-history, Cannabis sativa has been exploited for its potent and manifold pharmacological actions. Amongst the most renowned of these actions is a tendency to provoke ravenous eating. The characterization of the psychoactive principals in cannabis (exogenous cannabinoids) and, more recently, the discovery of specific brain cannabinoid receptors and their endogenous ligands (endocannabinoids) has stimulated research into the physiological roles of endocannabinoid systems. In this review, we critically discuss evidence from the literature that describe studies on animals and human subjects to support endocannabinoid involvement in the control of appetite. We describe the hyperphagic actions of the exogenous cannabinoid, Δ9-tetrahydrocannabinol, and the endogenous CB1 ligands, anandamide and 2-arachidonylglycerol, and present evidence to support a specific role of endocannabinoid systems in appetitive processes related to the incentive and reward properties of food. A case is made for more comprehensive and systematic analyses of cannabinoid actions on eating, in the anticipation of improved therapies for disorders of appetite and body weight, and a better understanding of the biopsychological processes underlying hunger.

Keywords

EndocannabinoidsAnandamideRewardAppetite regulation
Type
Research Article
Information
Nutrition Research Reviews , Volume 14 , Issue 1 , June 2001 , pp. 65 - 86
Copyright
Copyright © CABI Publishing 2001

References

Abel, EL (1971) Effects of marijuana on the solution of anagrams, memory and appetite. Nature 231, 260–261.Google Scholar
Abel, EL (1975) Cannabis: effects on hunger and thirst. Behavioral Biology 15, 255–281.Google Scholar
Abrahamov, A, Abrahamov, A & Mechoulam, R (1995) An efficient new cannabinoid antiemetic in pediatric oncology. Life Sciences 56, 2097–2102.Google Scholar
Arnone, M, Maruani, J, Chaperon, F, Thiebot, MH, Poncelet, M, Soubrié, P & LeFur, G (1997) Selective inhibition of sucrose and ethanol intake by SR141716, an antagonist of central cannabinoid (CB1) receptors. Psychopharmacology 132, 104–106.CrossRefGoogle ScholarPubMed
Beal, JE, Olson, R, Laubenstein, L, Morales, JO, Bellman, P, Yangco, B, Lefkowitz, L, Plasse, TF & Shepard, KV (1995) Dronabinol as a treatment for anorexia associated with weight loss in patients with AIDS. Journal of Pain & Symptom Management 10, 89–97.CrossRefGoogle ScholarPubMed
Berridge, K (1991) Modulation of taste affect by hunger, energy satiety, and sensory-specific satiety in the rat. Appetite 16, 103–120.Google Scholar
Berridge, K (2000) Measuring hedonic impact in animals and infants: microstructure of affective taste reactivity patterns. Neuroscience and Biobehavioral Reviews 24, 173–198.CrossRefGoogle ScholarPubMed
Bidaut-Russell, M & Howlett, AC (1991) Cannabinoid receptor regulated cAMP accumulation in the rat striatum. Journal of Neurochemistry 57, 1769–1773.CrossRefGoogle Scholar
Bivens, CLM, Thomas, WJ & Stanley, BG (1998) Similar feeding patterns are induced by perifornical neuropeptide Y injection and by food deprivation. Brain Research 782, 271–280.CrossRefGoogle Scholar
Breivogel, CS & Childers, SR (1998) The functional neuroanatomy of brain cannabinoid receptors. Neurobiology of Disease 5, 417–431.CrossRefGoogle ScholarPubMed
Breivogel, CS, Sim, LJ & Childers, SR (1997) Regional differences in cannabinoid receptor/G-protein coupling in rat brain. Journal of Pharmacology and Experimental Therapeutics 282, 1632–1642.Google Scholar
Brown, JE, Kassouny, M & Cross, JK (1977) Kinetic studies of food intake and sucrose solution preference by rats treated with low doses of delta-9-tetrahydrocannabinol. Behavioral Biology 20 104–110.Google Scholar
Burstein, SH, Young, JK & Wright, GE (1995) Relationships between eicosanoids and cannabinoids: are eicosanoids cannabimimetic agents. Biochemical Pharmacology 50, 1735–1742.Google Scholar
Cabeza de Vaca, S & Carr, KD (1998) Food restriction enhances the central rewarding effect of abused drugs. Journal of Neuroscience 18, 7502–7510.CrossRefGoogle ScholarPubMed
Cat, LK & Coleman, RL (1994) Treatment for HIV wasting syndrome. Annals of Pharmacotherapy 28, 595–597.Google ScholarPubMed
Colombo, G, Agabio, R, Diaz, G, Lobina, C, Reali, R & Gessa, GL (1998) Appetite suppression and weight loss after the cannabinoid antagonist SR141716. Life Sciences 63, PL113–PL117.Google Scholar
Clark, JT, Kalra, PS, Crowley, WR & Kalra, SP (1984) Neuropeptide Y and human pancreatic polypeptide stimulate feeding behaviour in rats. Endocrinology 115, 427–429.CrossRefGoogle ScholarPubMed
Clifton, PJ (2000) Meal patterning in rodents: psychopharmacological and neuroanatomical studies. Neuroscience and Biobehavioral Reviews 24, 213–222.Google Scholar
Cooper, SJ & Clifton, PJ (1996) Drug Receptor Subtypes and Ingestive Behaviour. London: Academic Press.Google Scholar
Cooper, SJ & Kirkham, TC (1993) Opioid mechanisms in the control of food consumption and taste preferences. In Handbook of Experimental Pharmacology, vol. 104, part II, pp. 239–263 [Herz, A, Akil, H & Simon, EJ editors]. Berlin: Springer–Verlag.Google Scholar
Crawley, JN, Corwin, RL, Robinson, JK, Felder, CC, Devane, WA & Axelrod, JA (1993) Anandamide, an endogenous ligand of the cannabinoid receptor, induces hypomotility and hypothermia in vivo in rodents. Pharmacology Biochemistry and Behavior 46, 967–972.CrossRefGoogle ScholarPubMed
De Petrocellis, L, Melck, D, Bisogno, T, Milone, A & Di Marzo, V (1999) Finding of the endocannabinoid signalling system in Hydra, a very primitive organism: possible role in the feeding response. Neuroscience 92, 377–387.CrossRefGoogle ScholarPubMed
Devane, WA, Dysarz, FA, Johnson, MR, Melvin, LS & Howlett, AC (1988) Determination and characterisation of a cannabinoid receptor in rat brain. Molecular Pharmacology 34, 605–613.Google ScholarPubMed
Devane, WA, Hanus, L, Breuer, A, Pertwee, RG, Stevenson, LA, Griffin, G, Gibson, D, Mandelbaum, A, Etinger, A & Mechoulam, R (1992) Isolation of a brain constituent that binds to the cannabinoid receptor. Science 258, 1946–1949.Google Scholar
Dewey, WL (1986) Cannabinoid pharmacology. Pharmacological Reviews 38, 151–178.Google Scholar
DiMarzo, V, Bifulco, M & De Petrocellis, L (2000) Endocannabinoids and multiple sclerosis: a blessing from the ‘inner bliss’? Trends in Pharmacological Sciences 21, 195–197.Google Scholar
Di Marzo, V & Deutsch, DG (1998) Biochemistry of endogenous ligands of cannabinoid receptors. Neurobiology of Disease 5, 386–404.Google Scholar
Di Marzo, V, Melck, D, Bisogno, T & De Petrocellis, L (1998) Endocannabinoids: endogenous cannabinoid receptor ligands with neuromodulatory action. Trends in Neurosciences 21, 521–528.Google Scholar
Drewnowski, A & Grinker, JA (1978) Food and water intake, meal patterns and activity of obese and lean Zucker rats following chronic and acute treatment with Δ9-tetrahydrocannabinol. Pharmacology Biochemistry and Behavior 9, 619–630.Google Scholar
Edwards, CM, Abusnana, S, Sunter, D, Murphy, KG, Ghatei, MA & Bloom, SR (1999) The effect of the orexins on food intake: comparison with neuropeptide Y, melanin-concentrating hormone and galanin. Journal of Endocrinology 160, R7–R12.Google Scholar
Fimiani, C, Liberty, T, Aquirre, AJ, Amin, I, Ali, N & Stefano, GB (1999) Opiate, cannabinoid, and eicosanoid signalling converges on common intracellular pathways nitric oxide coupling. Prostaglandins & Other Lipid Mediators 57, 23–34.Google Scholar
Foltin, RW, Brady, JV & Fischman, MW (1986) Behavioral analysis of marijuana effects on food intake in humans. Pharmacology Biochemistry and Behavior 25, 577–582.Google Scholar
Foltin, RW, Fischman, MW & Byrne, MF (1988) Effects of smoked marijuana on food intake and body weight of humans living in a residential laboratory. Appetite 11, 1–14.Google Scholar
Fuentes, JA, Ruiz Gayo, M, Manzanares, J, Vela, G, Reche, I & Corchero, J (1999) Cannabinoids as potential new analgesics. Life Sciences 65, 675–685.Google Scholar
Gallate, JE & McGregor, IS (1999) The motivation for beer in rats: effects of ritanserin, naloxone and SR141716. Psychopharmacology 142, 302–308.Google Scholar
Gallate, JE, Saharov, T, Mallet, PE & McGregor, IS (1999) Increased motivation for beer in rats following administration of a cannabinoid CB1 receptor agonist. European Journal of Pharmacology 370, 233–240.Google Scholar
Gaoni, Y & Mechoulam, R (1964) Isolation, structure and partial synthesis of an active constituent of hashish. Journal of the American Chemical Society 86, 1646.CrossRefGoogle Scholar
Gardner, EL (1992) Cannabinoid interaction with brain reward systems – the neurobiological basis of cannabinoid abuse. In Marijuana/Cannabinoids: Neurobiology and Neurophysiology, pp. 275–335 [Murphy, LL and Bartke, A editorsC:\cup\Parser]. New York, NY: CRC Press.Google Scholar
Gardner, EL, Paredes, W, Smith, D, Donner, A, Milling, C, Cohen, D & Morrison, D (1988) Facilitation of brain stimulation reward by Δ-9-tetrahydrocannabinol. Psychopharmacology 96, 142–144.Google Scholar
Gardner, EL & Vorel, SR (1998) Cannabinoid transmission and reward-related events. Neurobiology of Disease 5, 502–533.Google Scholar
Glass, M, Dragunow, M & Faull, RLM (1997) Cannabinoid receptors in the human brain: A detailed anatomical and quantitative autoradiographic study in the fetal, neonatal and adult human brain. Neuroscience 77, 299–318.Google Scholar
Glick, SD & Milloy, S (1972) Increased and decreased eating following THC administration. Psychonomic Science 29, 6.Google Scholar
Gorter, RW (1999) Cancer cachexia and cannabinoids. Forsch Komplemetarmed 6, Suppl. 3, 21–22.Google ScholarPubMed
Gosnell, BA, Krahn, DD & Majchrzak, MJ (1990) The effects of morphine on diet selection are dependent on base-line diet preferences. Pharmacology Biochemistry and Behavior 37, 207–212.Google Scholar
Graceffo, TJ & Robinson, JK (1998) Delta-9-tetrahydrocannabinol (THC) fails to stimulate consumption of a highly palatable food in the rat. Life Sciences 62, 85–88.Google Scholar
Gralla, RJ (1999) Cannabinoids and the control of chemotherapy-induced nausea and vomiting. In Marihuana and Medicine, pp. 599–610 [Nahas, GG, Sutin, KM, Harvey, DJ & Agurell, S editors]. Totowa, NJ: Humana Press.Google Scholar
Greenberg, I, Kuehnle, J, Mendelson, JH & Bernstein, JG (1976) Effects of marijuana use on body weight and energy intake in humans. Psychopharmacology 49, 79–84.Google Scholar
Haines, L & Green, W (1970) Marijuana use patterns. British Journal of Addiction 65, 347–362.Google ScholarPubMed
Halikas, JA, Goodwin, DW & Guze, SB (1971) Marijuana effects. A survey of regular users. Journal of the American Medical Association 217, 692–694.CrossRefGoogle ScholarPubMed
Hampson, AJ, Grimaldi, M, Lolic, M, Wink, D, Rosenthal, R & Axelrod, J (2000) Neuroprotective antioxidants from marijuana. Annals of the New York Academy of Sciences 899, 274–282.Google Scholar
Hao, S, Mechoulam, R & Berry, EM (2000) Low dose anandamide affects food intake, cognitive function, neurotransmitter and corticosterone levels in diet-restricted mice. European Journal of Pharmacology 392, 147–156.CrossRefGoogle ScholarPubMed
Herkenham, M, Lynn, AB, Little, MD, Johnson, MR, Melvin, LS, De Costa, BR & Rice, KC (1990) Cannabinoid receptor localisation in brain. Proceedings of the National Academy of Sciences USA 87, 1932–1936.Google Scholar
Hoebel, BG (1997) Neuroscience and appetitive behavior research: 25 years. Appetite 29, 119–133.Google Scholar
Hollister, LE (1971) Hunger and appetite after single doses of marijuana, alcohol and dextroamphetamine. Clinical Pharmacology and Therapeutics 14, 45–49.Google Scholar
Hollister, LE (1986) Health aspects of cannabis. Pharmacological Reviews 38, 1–20.Google Scholar
Holst, JJ (1999) Glucagon-like peptide 1 (GLP-1): an intestinal hormone, signalling nutritional abundance, with an unusual therapeutic potential. Trends in Endocrinology and Metabolism 10, 229–235.CrossRefGoogle ScholarPubMed
Ikemoto, S & Panksepp, J (1999) The role of nucleus accumbens dopamine in motivated behavior: a unifying interpretation with special reference to reward-seeking. Brain Research Reviews 31, 6–41.Google Scholar
Johnson, SW & North, RA (1992) Opioids excite dopamine neurons by hyperpolarization of local interneurons. Journal of Neuroscience 14, 483–488.Google Scholar
Kelley, AE (1999) Functional specificity of ventral striatal compartments in appetitive behaviors. Annals of the New York Academy of Sciences 877, 71–90.Google Scholar
Kirkham, TC (1990) Enhanced anorectic potency of naloxone in rats sham feeding 30% sucrose: reversal by repeated naloxone administration. Physiology and Behavior 47, 419–426.Google Scholar
Kirkham, TC & Cooper, SJ (1988) Naloxone attenuation of sham feeding is modified by manipulation of sucrose concentration. Physiology and Behavior 44, 491–494.Google Scholar
Kirkham, TC & Cooper, SJ (1991) Opioid peptides in relation to the treatment of obesity and bulimia. In Peptides: A Target for New Drug Development, pp. 28–44 [Bloom, SR & Burnstock, G editors]. London: IBC.Google Scholar
Kirkham, TC & Williams, CM (1998) The cannabinoid receptor antagonist SR141716 fails to suppress sucrose sham feeding. Journal of Psychopharmacology 14, Suppl. A, 37.Google Scholar
Kirkham, TC & Williams, CM (1999) Central administration of anandamide induces hyperphagia in satiated rats. Society for Neuroscience Abstracts 25, 1885.Google Scholar
Kirkham, TC & Williams, CM (2001) Synergistic effects of opioid and cannabinoid antagonists on food intake. Psychopharmacology 153, 267–270.CrossRefGoogle ScholarPubMed
Ledent, C, Valverde, O, Cossu, G, Petite, F, Aubert, J-F, Baslet, F, Bohme, GA, Imperato, A, Pedrazzini, T, Roques, BP, Vassert, G, Fratta, W & Parmentier, M (1999) Unresponsiveness to cannabinoids and reduced addictive effects of opiates in CB1 receptor knockout mice. Science 283, 401–404.Google Scholar
Leventhal, L, Kirkham, TC, Cole, JL, Bodnar, RJ (1995) Selective actions of central mu and kappa opioid antagonists upon sucrose intake in sham-feeding rats. Brain Research 685, 205–210.CrossRefGoogle Scholar
McLaughlin, CL, Baile, CA & Bender, PE (1979) Cannabinols and feeding in sheep. Psychopharmacology 64, 321–323.Google Scholar
Manning, FJ, McDonough, JH, Elsmore, TF, Saller, C & Sodetz, FJ (1971) Inhibition of normal growth by chronic administration of Δ9-tetrahydrocannabinol. Science 174, 424–426.Google Scholar
Marsicano, G & Lutz, B (1999) Expression of the cannabinoid receptor CB1 in distinct neuronal subpopulations in the adult mouse forebrain. European Journal of Neuroscience 11, 4213–4225.Google Scholar
Mascia, MS, Obinu, MC, Ledent, C, Parmentier, M, Bohme, GA, Imperato, A & Fratta, W (1999) Lack of morphine-induced dopamine release in the nucleus accumbens of cannabinoid CB1 receptor knockout mice. European Journal of Pharmacology 383, R1–R2.Google Scholar
Matsuda, LA, Lolait, SJ, Brownstein, MJ, Young, AC & Bonner, TI (1990) Structure of a cannabinoid receptor and functional expression of the cloned cDNA. Nature 346, 561–564.Google Scholar
Mattes, RD, Engelman, K, Shaw, LM & Elsohly, MA (1994) Cannabinoids and appetite stimulation. Pharmacology Biochemistry and Behavior 49, 187–195.Google Scholar
Mechoulam, R, Ben-Shabat, S, Hanus, L, Ligumsky, M, Kaminski, NE, Schatz, AR, Gopher, A, Almog, S, Martin, BR, Compton, DR, Pertwee, RG, Griffin, G, Bayewitch, M, Barg, J & Vogel, Z (1995) Identification of an endogenous 2-monoglyceride, present in canine gut, that binds to cannabinoid receptors. Biochemical Pharmacology 50, 83–90.Google Scholar
Mechoulam, R, Shani, A, Edery, H & Grunfield, Y (1970) Chemical basis of hashish activity. Science 169, 611.Google Scholar
Mela, DJ & Rogers, PJ (1998) Food Eating and Obesity. London: Chapman and Hall.CrossRefGoogle Scholar
Munro, S, Thomas, KL & Abu-Shaar, M (1993) Molecular characterisation of a peripheral receptor for cannabinoids. Nature 365, 61–65.Google Scholar
Nahas, GG, Sutin, KM, Harvey, DJ & Agurell, S (1999) Marihuana and Medicine. Totowa, NJ: Humana Press.Google Scholar
Onaivi, ES, Chakrabarti, A & Chaudhuri, G (1996) Cannabinoid receptor genes. Progress in Neurobiology 48, 275–305.Google Scholar
Pertwee, RG (1995) Cannabinoid Receptors. London: Academic Press.Google Scholar
Pertwee, RG (2000) Neuropharmacology and therapeutic potential of cannabinoids. Addiction Biology 5, 37–46.Google Scholar
Piomelli, D, Beltramo, M, Giuffrida, A & Stella, N (1998) Endogenous cannabinoid signaling. Neurobiology of Disease 5, 462–473.Google Scholar
Plasse, TF, Gorter, RW, Krasnow, SH, Lane, M, Shepard, KY & Wadleigh, RG (1991) Recent clinical experience with dronabinol. Pharmacology Biochemistry and Behavior 40, 695–700.Google Scholar
Regelson, W, Butler, JR & Schultz, J (1976) Delta-9-tetrahydrocannabinol as an effective antidepressant and appetite-stimulating agent in advanced cancer patients. In The Pharmacology of Marijuana, pp. 763–776 [Braude, MC & Szara, S editors]. New York, NY: Raven Press.Google Scholar
Reggio, PH (1999) Cannabinoid receptors. Tocris Reviews 10, 1–5.Google Scholar
Rodriguez de Fonseca, F, Martinz Calderon, JL, Mechoulam, R & Navarro, M (1994) Repeated stimulation of D1 dopamine receptors enhances (2)-11-hydroxy-delta-8-tetrahydrocannabinol-dimethyl-heptyl-induced catalepsy in male rats. Neuroreport 5, 761–765.CrossRefGoogle ScholarPubMed
Rodriguez de Fonseca, F, Roberts, AJ, Bilbao, A, Koob, GF & Navarro, M (1999) Cannabinoid receptor antagonist SR141716 decreases operant ethanol self administration in rats exposed to ethanol-vapor chambers. Acta Pharmacologica Sinica 20, 1109–1114.Google Scholar
Sacks, N, Hutcheson, JR, Watts, JM & Webb, RE (1990) Case report: the effect of tetrahydrocannabinol on food intake during chemotherapy. Journal of the American College of Nutrition 9, 630–632.Google Scholar
Sanudo-Pena, MC, Patrick, SL, Patrick, RL & Walker, JM (1996) Effects of intranigral cannabinoids on rotational behaviour in rats: Interaction with the dopaminergic system. Neuroscience Letters 206, 21–24.Google Scholar
Schwartz, MW, Woods, SC, Porte, D Jr, Seeley, RJ & Baskin, DG (2000) Central nervous system control of food intake. Nature 404, 661–671.Google Scholar
Simiand, J, Keane, M, Keane, PE & Soubrie, P (1998) SR141716, a CB1 cannabinoid receptor antagonist, selectively reduces sweet food intake in marmoset. Behavioural Pharmacology 9, 179–181.Google Scholar
Sjoden, P-O, Jarbe, TUC & Henriksson, BG (1973) Influence of tetrahydrocannabinols (Δ-8-THC and Δ-9-THC) on body weight, food and water intake in rats. Pharmacology Biochemistry and Behavior 1, 395–399.Google Scholar
Soderstrom, K, Leid, M, Moore, FL & Murray, TF (2000) Behavioral, pharmacological, and molecular characterization of an amphibian cannabinoid receptor. Journal of Neurochemistry 75, 413–423.Google Scholar
Sofia, RD & Barry, H (1974) Acute and chronic effects of Δ-9-tetrahydrocannabinol on food intake by rats. Psychopharmacologia 39, 213–222.Google Scholar
Souilhac, J, Poncelet, M, Rinaldi-Carmona, M, Le Fur, G & Soubrie, P (1995) Intrastriatal injection of cannabinoid receptor agonists induced turning behavior in mice. Pharmacology Biochemistry and Behavior 51, 3–7.Google Scholar
Spanagel, R & Weiss, F (1999) The dopamine hypothesis of reward: past and current status. Trends in Neurosciences 22, 521–527.Google Scholar
Stella, N, Schweitzer, P & Piomelli, D (1997) A second endogenous cannabinoid that modulates long-term potentiation. Nature 388, 773–778.Google Scholar
Stratford, TR, Swanson, CJ & Kelley, A (1998) Specific changes in food intake elicited by blockade or activation of glutamate receptors in the nucleus accumbens shell. Behavioral Brain Research 93, 43–50.Google Scholar
Stuwe, M, Kaempfer, SH, Geiger, CJ, Pavia, AT, Plasse, TF, Shepard, KV, Ries, K & Evans, TG (1993) Effect of dronabinol on nutritional status in HIV infection. Annals of Pharmacotherapy 27, 827–831.Google Scholar
Tanda, G, Pontieri, FE & DiChiara, G (1997) Cannabinoid and heroin activation of mesolimbic dopamine transmission by a common μ1 opioid receptor mechanism. Science 276, 2048–2050.Google Scholar
Tart, C (1970) Marijuana intoxication: common experiences. Nature 226, 701–704.Google Scholar
Trojniar, W & Wise, RA (1991) Facilitory effect of Δ-9-tetrahydrocannabinol on hypothalamically-induced feeding. Psychopharmacology 103, 172–176.Google Scholar
Volicer, L (1997) Dronabinol may help behaviour problems in Alzheimers disease. American Family Physician 55, 1338.Google Scholar
Weingarten, HP & Watson, SD (1982) Sham feeding as a procedure for assessing the influence of diet palatability on food intake. Physiology and Behavior 28, 401–407.Google Scholar
Welch, SP & Eads, EM (1999) Synergistic interactions of endogenous opioids and cannabinoid systems. Brain Research 848, 183–190.Google Scholar
Williams, CM, Rogers, PJ & Kirkham, TC (1998) Hyperphagia in pre-fed rats following oral Δ-9-THC. Physiology and Behavior 65, 343–346.Google Scholar
Williams, CM & Kirkham, TC (1999 a) Anandamide induces overeating: mediation by central cannabinoid receptors. Psychopharmacology 143, 315–317.Google Scholar
Williams, CM & Kirkham, TC (1999 b). Observational analysis of Δ9-THC effects on feeding microstructure in rats. Journal of Psychopharmacology 13 (3, Suppl. A), 20.Google Scholar