Does Morphine Affect Astrocytes?

Abstract

Astrocytes in primary culture express receptors for monoamine and peptide neurotransmitters. The cells also exhibit uptake sites for amino acid neurotransmitters. New data is presented, demonstrating interactions between the second messenger systems for vasoactive intestinal peptide (VIP) and α- and β-adrenoceptors. Stimulation of these monoamine receptors modulates GABA and glutamate uptake into the cells, which indicates that astrocytes have the capacity to supervise and regulate synaptic transmission. Morphine affects astrocytes directly, probably by interaction with α₂ receptors, and indirectly by drug-induced ionic changes in the synaptic region, followed by changes in neurotransmission and protein synthesis.

Modulation of astroglial specific functions or metabolism might be one way to affect functional neuronal disturbances, including an approach toward understanding the underlying cellular mechanisms, e.g. tolerance.

Keywords

morphine astroglial primary culture GABA glutamate monoamine neuropeptide uptake carrier receptor cyclic AMP

Get full access to this article

View all access options for this article.

References

Hansson

(1988). Astroglia from defined brain regions as studied with primary cultures. Progress in Neurobiology, in press.

Arenander

A.T.

, & de Vellis

(1982). Glial-released proteins in neural intercellular communications: molecular mapping, modulation, and influence, on neuronal differentiation. In Proteins in the Nervous Systems: Structure and Function (ed. Haber

, Perez-Polo

J.R.

, and Coulter

J.D.

), pp. 243–269. Alan R. Liss, Inc., 150 Fifth Avenue, New York, New York 10011.

Hansson

, & Rönnbäck

(1985). Amino acid incorporation during morphine intoxication, Part 2, Electrophoretic separation of extracellular proteins from cerebral hemisphere slices and astroglial-enriched primary cultures. Journal of Neuroscience Research 14, 479–490.

Hansson

(1984). Cellular composition of a cerebral hemisphere primary culture. Neurochemical Research 9, 153–172.

Hansson

(1986). Primary astroglial cultures. A biochemical and functional evaluation. Neurochemical Research 11, 759–766.

Peters

, Palay

S.L.

, & Webster

H. de F.

, eds. (1976). The Fine Structure of the Nervous System: The Neurons and Supporting Cells. Philadelphia, London, Toronto: W.B. Saunders Company.

McCarthy

K.D.

, Prime

, Harmon

, and Pollenz

(1985). Receptor-mediated phosphorylation of astroglial intermediate filament proteins in cultured astroglia. Journal of Neurochemistry 44, 723–730.

Hansson

, Rönnbäck

, & Sellstrom

Å.

(1984). Is there a “dopaminergic glial cell”? Neurochemical Research 9, 679–689.

Hösli

, & Hösli

(1986). Binding sites for ³H-dopamine and dopamine-antagonists on cultured astrocytes of rat striatum and spinal cord: an autodiagraphic study. Neuroscience Letters 65, 177–182.

10.

Hansson

, & Rönnbäck

(1987). Interaction between catetholamines and vasoactive intestinal peptide in cultured astrocytes. Neuropharmacology, in press.

11.

Hansson

, Simonsson

, and Ailing

(1987). 5-Hydroxytryptamine stimulates the formation of inositol phosphate in astrocytes from different regions of the brain. Neuropharmacology, 26, 1377–1382.

12.

Drejer

, Larsson

O.M.

, and Schousboe

(1982). Characterization of L-glutamate uptake into and release from astrocytes and neurons cultured from different brain regions. Experimental Brain Research 47, 259–269.

13.

Hansson

, Eriksson

, and Nilsson

(1985). Amino acid and monoamine transport in primary astroglial cultures from defined brain regions. Neurochemical Research 10, 1335–1341.

14.

Hansson

, & Rönnbäck

(1983). Incorporation of ³H-valine into soluble protein of cultivated astroglial cells after morphine treatment. Journal of Neuroscience Research 10, 279–288.

15.

Bunn

S.J.

, Hanley

M.R.

, and Wilkin

G.P.

(1985). Evidence for a kappa-opioid receptor on pituitary astrocytes: an autoradiographic study. Neuroscience Letters 55, 317–323.

16.

Plishka

R.J.

, and Neale

J.H.

(1984). Morphine treatment increases clonidine binding in brain cell cultures. Neuroscience Letters 51, 281–286.

17.

Pearce

, Cambray-Deakin

, and Murphy

(1985). Astrocyte opioid receptors: activation modifies the noradrenaline-evoked increase in 2-(¹⁴C) deoxyglucose incorporation into glycogen. Neuroscience Letters 55, 157–160.