Electrophysiological and biochemical evidence for bradykinin receptors on cultured rat cortical oligodendrocytes.
The effects of the neuropeptide bradykinin (Bk) were examined on antigenically-identified rat cortical oligodendrocytes. Bk significantly increased the incorporation of [3H]myo-inositol into phospholipids, indicating the turnover of phosphatidyl inositol (PI). Ca2+ flux analysis experiments confirmed that this effect was accompanied by an increase in intracellular Ca2+. Using the whole-cell patch clamp technique, Bk was shown to induce an inward current associated with a decrease in membrane conductance, indicating a closure of ion channels. The reversal potential of the current was close to the potassium equilibrium potential, consistent with an effect on a K+ conductance in these cells. These results show that oligodendrocytes possess Bk receptors that may be of functional relevance.
Department of Biochemistry, Imperial College of Science, Technology and Medicine, London, UK.
G J
GJ
Stephens
D R
DR
Marriott
M B
MB
Djamgoz
G P
GP
Wilkin
D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D001920:Bradykinin / Q000378:metabolism*; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000378:metabolism*; D004594:Electrophysiology; D005699:Galactosylceramides / Q000276:immunology / Q000378:metabolism; D007150:Immunohistochemistry; D007294:Inositol / Q000378:metabolism; D007295:Inositol Phosphates / Q000276:immunology / Q000378:metabolism; D009836:Oligodendroglia / Q000378:metabolism*; D015221:Potassium Channels / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D018002:Receptors, Bradykinin; D017981:Receptors, Neurotransmitter / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*
D000911:Antibodies, Monoclonal; D005699:Galactosylceramides; D007295:Inositol Phosphates; D015221:Potassium Channels; D018002:Receptors, Bradykinin; D017981:Receptors, Neurotransmitter; D007294:Inositol; D001920:Bradykinin