In Vivo Evidence that Nonneuronal β‐Adrenoceptors as Well as Dopamine Receptors Contribute to Cyclic AMP Efflux in Rat Striatum

摘要: We applied in vivo microdialysis to assess the effects of dopaminergic and beta-adrenergic receptor stimulation on cyclic AMP efflux rat striatum under chloral hydrate anesthesia. Dopamine (up 1 mM) infused for 20 min through probe did not increase AMP, whereas both selective dopamine D1 agonist SKF 38393 D2 antagonist sulpiride produced modest increases. It is interesting that beta-adrenoceptor isoproterenol a marked (204.7% basal level at which was antagonized by propranolol. Pretreatment with glial metabolic inhibitor, fluorocitrate (1 mM), 5-h infusion attenuated 30.3% significantly blocked response isoproterenol. By contrast, striatal injection neurotoxin, kainic acid (2.5 micrograms), 2 days before dialysis experiment affect or isoproterenol, but 38393. These data demonstrate beta-adrenoceptors as well receptors contribute vivo. They also suggest beta-adrenoceptor-stimulated are substantially dependent intact cells.