Enkephalin effects on release of brain acetylcholine


MORPHINE and other narcotic analgesics depress the spontaneous release of acetylcholine (ACh) from the rat cerebral cortex in vivo1,2. The effect of these agents on the central release of ACh, like their inhibitory effects on the peripheral release of ACh in the guinea pig ileum, is stereospecific3 and can be fully antagonised by naloxone4. It is well recognised that the endogenous opiate peptides, enkephalins5,6 and endorphins7, depress the output of ACh from the electrically stimulated guinea pig ileum by a specific action on opiate receptors. This suggests that in the central nervous system endogenous opiates may exert a significant influence on the release of ACh. We have examined the effects of two enkephalins, methionine-enkephalin (Met-enkephalin) and leucine-enkephalin (Leu-enkephalin) on the cortical release of ACh in vivo following intraventricular injections. Our observations show that natural enkephalins may interact with opiate receptors in the brain to modulate the release of ACh from the cholinergic neurones.

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  1. 1

    Matthews, J. D., Labrecque, G. & Domino, E. F. Psychopharmacologia 29, 113–120(1973).

    CAS  Article  Google Scholar 

  2. 2

    Jhamandas, K. & Sutak, M. Br. J. Pharmac. 50, 57–62 (1974).

    CAS  Article  Google Scholar 

  3. 3

    Jhamandas, K., Hron, V. & Sutak, M. Can. J. Pharmac. Physiol. 50, 540–548 (1975).

    Article  Google Scholar 

  4. 4

    Jhamandas, K. & Sutak, M. Br. J. Pharmac. 58, 101–107 (1976).

    CAS  Article  Google Scholar 

  5. 5

    Hughes, J. Brain Res. 88, 295–308 (1975).

    ADS  CAS  Article  Google Scholar 

  6. 6

    Hughes, J., Smith, T. W., Kosterlitz, H. W., Fothergill, L. A., Morgan, B. A. & Morris, H. R. Nature 258, 577–579 (1975).

    ADS  CAS  Article  Google Scholar 

  7. 7

    Goldstein, A. Science 193, 1081–1086 (1976).

    ADS  CAS  Article  Google Scholar 

  8. 8

    MacIntosh, F. C. & Oborin, P. E. Abstr. XIX Int. Physiol. Cong. 580–581 (1953).

  9. 9

    Mullin, W. J., Phillis, J. W. & Pinsky, C. Eur. J. Pharmac. 22, 117–119 (1973).

    CAS  Article  Google Scholar 

  10. 10

    Nistri, A. Brain Res. 110, 403–406 (1976).

    CAS  Article  Google Scholar 

  11. 11

    Simantov, R. & Snyder, S. H. Molec. Pharmac. 12, 987–998 (1976).

    CAS  Google Scholar 

  12. 12

    Taube, H. D., Borowski, E., Endo, T. & Starke, K. Eur. J. Pharmac. 38, 377–380 (1976).

    CAS  Article  Google Scholar 

  13. 13

    Loh, H. H., Brase, D. A., Sumathy, S. K., Jeffrey, B. M., Way, E. L. & Li, C. H. Nature 264, 567–568 (1976).

    ADS  CAS  Article  Google Scholar 

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JHAMANDAS, K., SAWYNOK, J. & SUTAK, M. Enkephalin effects on release of brain acetylcholine. Nature 269, 433–434 (1977). https://doi.org/10.1038/269433a0

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