Cross-talk between different intracellular signalling pathways in the rat hippocampus.
The activation of alpha 1-adrenergic receptors in rat hippocampal slices enhances polyphosphoinositide (PPI) breakdown and cyclicAMP (cAMP) accumulation. The latter effect is antagonized by different protein kinase C (PKC) inhibitors and mimicked by a diacylglycerol (DAG) analogue, 1,2-diolein, which activates PKC, suggesting that cAMP synthesis is indirectly affected by alpha 1-adrenoceptors through the stimulated generation of DAG upon PPI hydrolysis. Furthermore the elevation of hippocampal cAMP decreases the ability of alpha 1-receptor agonists to enhance PPI breakdown. It is proposed that the observed effects are part of a complex cross-talk between PPI and AC signalling pathways operating in hippocampal neurons.
Parenti
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M
E. Trabucchi Department of Pharmacology, University of Milano, Italy.
Ceresoli
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G
Consolo
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S
Groppetti
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A
D000818:Animals; D000242:Cyclic AMP / Q000502:physiology*; D006624:Hippocampus / Q000502:physiology*; D066298:In Vitro Techniques; D010716:Phosphatidylinositols / Q000502:physiology*; D051381:Rats; D015290:Second Messenger Systems
D010716:Phosphatidylinositols; D000242:Cyclic AMP