cGMP acts within cerebellar Purkinje cells to produce long term depression via mechanisms involving PKC and PKG.
Long term depression (LTD) of parallel fibre-Purkinje cell responses may result from desensitization of AMPA (alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid) type glutamate receptors, for which a cascade of reactions involving calcium, inositol-1,4,5-trisphosphate, nitric oxide (NO), guanosine-3'5'-monophosphate (cGMP) and protein kinases C and G has been previously proposed. The involvement of cGMP in synaptic LTD was confirmed by direct injection of cGMP and 8-bromo-cGMP (8-Br-cGMP) into the dendrites of Purkinje cells. Pairing injections with parallel fibre stimulation led to a LTD of synaptic transmission which both occluded and was occluded by heterosynaptically induced LTD. Inhibition of either protein kinases C or G prevented induction of both forms of LTD.
Hartell
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NA
Laboratory for Neural Networks, RIKEN, Saitama, Japan.
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000594:Amino Acid Oxidoreductases / Q000037:antagonists & inhibitors; D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D006152:Cyclic GMP / Q000494:pharmacology*; D004594:Electrophysiology; D004789:Enzyme Activation; D019001:Nitric Oxide Synthase; D019335:Nitroarginine; D011189:Potassium Chloride / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism*; D011689:Purkinje Cells / Q000187:drug effects* / Q000502:physiology*; D051381:Rats
D019335:Nitroarginine; D015124:8-Bromo Cyclic Adenosine Monophosphate; D011189:Potassium Chloride; D001120:Arginine; D019001:Nitric Oxide Synthase; D000594:Amino Acid Oxidoreductases; D011493:Protein Kinase C; D006152:Cyclic GMP; D015056:1-Methyl-3-isobutylxanthine