Abstract
THE overt behaviour of various species is affected in different ways by opiate drugs. Mice and cats show behavioural stimulation following a systemic morphine injection whereas rats and dogs generally exhibit decreased behavioural activity1–4, although in certain conditions, stimulant effects can also be seen in the latter species4,5. Tatum et al. suggested that there are several distinct sites of action of opiate drugs in brain and that the relative dominance of one system over another determines whether the stimulant or depressant effects predominate4. Indeed, direct microinjections of morphine into the ventral tegmental area (VTA) have been shown to result in facilitation of self-stimulation behaviour whereas similar injections into the periaqueductal gray matter cause only an attenuation of this behaviour6. The discovery of endogenous ligands for opiate receptors in the brain7 has focused attention on the role of these peptides in various aspects of behaviour. Their analgesic properties following intr a ventricular and intracerebral injection are well documented8. Recently, it has been reported that infusion of α-endorphin into the substantia nigra induced stereotyped behaviour9, whereas local injections into the nucleus accumbens of the long-acting synthetic enkephalin analogue, [D-Ala2]-Met5-enkephalinamide (AME), produced an increase in locomotor activity10. We now report that infusion of AME (0.03–2.0 µg) bilaterally into the dopaminergic (DA) A10 area of the VTA induces a short-latency behavioural stimulant effect reminiscent of effects produced by stimulation of the mesolimbic DA pathway11. This effect is antagonised by pretreatment with the opiate receptor blocker naloxone.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on SpringerLink
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Caroll, B. J. & Sharp, P. T. Br. J. Pharmac. 46, 124–139 (1972).
Cools, A. R., Janssen, H. J. & Broekkamp, C. L. E. Archs int. Pharmacodyn. 210, 163–174 (1974).
Kuschinsky, K. & Hornykiewicz, O. Eur. J. Pharmac. 19, 119–122 (1972).
Tatum, A. L., Seevers, M. H. & Collins, K. H. J. Pharmac. exp. Ther. 36, 447–475 (1929).
Ayhan, I. H. & Randrup, A. Psychopharmacology 29, 317–328 (1973).
Broekkamp, C. L. E., van Dongen, P. A. M. & van Rossum, J. M. in Psychobiology of the Striatum (eds Cools, A. R., Lohman, A. H. M. & van den Bercken, J. H. L.) 61–72 (North-Holland, Amsterdam, 1977).
Hughes, J., Smith, T., Morgan, B. & Fothergill, L. Life Sci. 16, 1753–1758 (1975).
Yask, T. L. & Rudy, T. A. Pain 4, 299–359 (1978).
Iwamoto, E. T. & Way, E. L. J. Pharmac. exp. Ther. 203, 347–359 (1977).
Pert, A. & Sivit, C. Nature 265, 645–647 (1977).
Pijnenburg, A. J. J. & van Rossum, J. M. J. Pharm. Pharmac. 25, 1003–1005 (1973).
Bergmann, F. et al. Experientia 33, 217 (1977).
Uhl, G. R., Goodman, R. R., Kuhar, M. J. & Snyder, S. H. in Advances in Biochemistry and Psychopharmacology (eds Costa, E. & Trabucchi, M.) 71–87 (Raven, New York, 1978).
Lindvall, O. & Björklund, A. Acta physiol. scand. Suppl., 412, 1–48 (1974).
Kelly, P. H., Seviour, P. W. & Iversen, S. D. Brain Res. 94, 507–522 (1975).
Nowycky, M. C., Walters, J. R. & Roth, R. H. J. neural transmission 42, 99–116 (1978).
Phillips, A. G. & Fibiger, H. C. Can. J. Psychol. 32, 58–66 (1978).
Iversen, S. D. in Psychobiology of the Striatum (eds Cools, A. R., Lohman, A. H. M. & vanden Bercken, J. H. L.) 99–118 (North-Holland, Amsterdam, 1977).
Belluzzi, J. D. & Stein, L. Nature 266, 556–558 (1977).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
BROEKKAMP, C., PHILLIPS, A. & COOLS, A. Stimulant effects of enkephalin microinjection into the dopaminergic A10 area. Nature 278, 560–562 (1979). https://doi.org/10.1038/278560a0
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/278560a0
This article is cited by
-
Prolonged Effects of Repeated Social Defeat Stress on mRNA Expression and Function of μ-Opioid Receptors in the Ventral Tegmental Area of Rats
Neuropsychopharmacology (2005)
-
Sexual Behavior and Sex-Associated Environmental Cues Activate the Mesolimbic System in Male Rats
Neuropsychopharmacology (2004)
-
Rats rapidly develop tolerance to the locomotor-inhibiting effects of the novel neuropeptide orphanin FQ
Neurochemical Research (1996)
-
The effects of dopamine D1 and D2 receptor antagonists on the rewarding effects of δ1 and δ2 opioid receptor agonists in mice
Psychopharmacology (1996)
-
The CCKB antagonist PD-134,308 facilitates rewarding effects of endogenous enkephalins but does not induce place preference in rats
Psychopharmacology (1996)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.