Abstract
Rats with electrodes implanted in the posterior lateral hypothalamus and ventromedial tegmentum were trained to self-stimulate. Animals were treated (i.p.) first with α-methyl-p-tyrosine (α-MPT) and then L-DOPA; their self-stimulation rates and spontaneous behaviour were recorded. α-MPT (100 mg/kg) had an immediate and long lasting suppressive effect on self-stimulation, within the first half hour. L-DOPA administration failed to reinstate self-stimulation. Hypoactivity also followed α-MPT injections. While the behavioural changes were minimal after L-DOPA 50 mg/kg, a decrease of spontaneous activity and moderate hyper-reactivity were observed following L-DOPA at a dose of 200 mg/kg. Theoretical implications are discussed.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- BERTLER A., ROSENGREN E. On the distribution in brain of monoamines and of enzymes responsible for their formation. Experientia. 1959 Oct 15;15:382–384. doi: 10.1007/BF02158964. [DOI] [PubMed] [Google Scholar]
- BLASCHKO H., CHRUSCIEL T. L. The decarboxylation of amino acids related to tyrosine and their awakening action in reserpine-treated mice. J Physiol. 1960 May;151:272–284. doi: 10.1113/jphysiol.1960.sp006437. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Butcher L. L., Engel J. Behavioral and biochemical effects of L-dopa after peripheral decarboxylase inhibition. Brain Res. 1969 Sep;15(1):233–242. doi: 10.1016/0006-8993(69)90322-9. [DOI] [PubMed] [Google Scholar]
- Bédard P., Larochelle L., Poirier L. J., Sourkes T. L. Reversible effect of L-dopa on tremor and catatonia induced by alpha-methyl-p-tyrosine. Can J Physiol Pharmacol. 1970 Jan;48(1):82–84. doi: 10.1139/y70-013. [DOI] [PubMed] [Google Scholar]
- Cooper B. R., Black W. C., Paolino R. M. Decreased septal-forebrain and lateral hypothalamic reward after alpha methyl-p-tyrosine. Physiol Behav. 1971 Apr;6(4):425–429. doi: 10.1016/0031-9384(71)90178-8. [DOI] [PubMed] [Google Scholar]
- Gibson S., McGeer E. G., McGeer P. L. Effect of selective inhibitors of tyrosine and tryptophan hydroxylases on self-stimulation in the rat. Exp Neurol. 1970 May;27(2):283–290. doi: 10.1016/0014-4886(70)90221-9. [DOI] [PubMed] [Google Scholar]
- KLUVER H., BARRERA E. A method for the combined staining of cells and fibers in the nervous system. J Neuropathol Exp Neurol. 1953 Oct;12(4):400–403. doi: 10.1097/00005072-195312040-00008. [DOI] [PubMed] [Google Scholar]
- Moore K. E. Effects of alpha-methyltyrosine on brain catecholamines and conditioned behavior in guinea pigs. Life Sci. 1966 Jan;5(1):55–65. doi: 10.1016/0024-3205(66)90187-1. [DOI] [PubMed] [Google Scholar]
- Moore K. E., Rech R. H. Reversal of alpha-methyltyrosine-induced behavioural depression with dihydroxyphenylalanine and amphetamine. J Pharm Pharmacol. 1967 Jun;19(6):405–407. doi: 10.1111/j.2042-7158.1967.tb09571.x. [DOI] [PubMed] [Google Scholar]
- Poschel B. P., Ninteman F. W. Hypothalamic self-stimulation: its suppression by blockade of norepinephrine biosynthesis and reinstatement by methamphetamine. Life Sci. 1966 Jan;5(1):11–16. doi: 10.1016/0024-3205(66)90181-0. [DOI] [PubMed] [Google Scholar]
- SMITH C. B., DEWS P. B. Antagonism of locomotor suppressant effects of reserpine in mice. Psychopharmacologia. 1962 Mar 12;3:55–59. doi: 10.1007/BF00413107. [DOI] [PubMed] [Google Scholar]
- SPECTOR S., SJOERDSMA A., UDENFRIEND S. BLOCKADE OF ENDOGENOUS NOREPINEPHRINE SYNTHESIS BY ALPHA-METHYL-TYROSINE, AN INHIBITOR OF TYROSINE HYDROXYLASE. J Pharmacol Exp Ther. 1965 Jan;147:86–95. [PubMed] [Google Scholar]
- VAN ROSSUMJ MECHANISM OF THE CENTRAL STIMULANT ACTION OF ALPHA-METHYL-META-TYROSINE. Psychopharmacologia. 1963 May 21;4:271–280. doi: 10.1007/BF00408182. [DOI] [PubMed] [Google Scholar]
- Weissman A., Koe B. K. Behavioral effects of L-alpha-methyltyrosine, an inhibitor of tyrosine hydroxylase. Life Sci. 1965 May;4(10):1037–1048. doi: 10.1016/0024-3205(65)90223-7. [DOI] [PubMed] [Google Scholar]