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PubMed · 1697379

Angiotensin II inhibits cortical cholinergic function: implications for cognition.

J M Barnes·N M Barnes·B Costall·Z P Horovitz·J W Ironside·R J Naylor·T J Williams
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Abstract

In the present studies we have shown that angiotensin II (AT II), in a concentration-dependent manner in rat tissue (10(-9)-10(-5) M) or at a single concentration in human tissue (10(-6) M), can inhibit potassium-stimulated release of [3H]acetylcholine ( [3H]Ach) from slices of rat entorhinal cortex and human temporal cortex preloaded with [3H]choline for the biochemical analyses. The inhibitory effects of AT II (10(-6) M) were antagonised by the specific AT II receptor antagonist [1-sarcosine, 8-threonine]AT II in a concentration-dependent manner in rat tissue (10(-11)-10(-8) M) and at the single concentration employed in the human studies (10(-7) M). Also demonstrated were other components of the angiotensin system in the human temporal cortex; ACE activity was present (1.03 nmol min-1 mg-1 protein), as were AT II recognition sites (Bmax = 8.6 fmol mg-1 protein). It is hypothesised that the potential cognitive enhancing properties of ACE inhibitors may reflect their action to prevent the formation of AT II and so remove an inhibitory modulator of cholinergic function.

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AcetylcholineAngiotensin IIAnimalsCerebral CortexCognitionFemaleIodine RadioisotopesParasympathetic Nervous SystemPotassiumRatsJournal ArticleResearch Support, Non-U.S. Gov't

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J M Barnes, N M Barnes, B Costall, Z P Horovitz, J W Ironside, R J Naylor, T J Williams. 1990. Angiotensin II inhibits cortical cholinergic function: implications for cognition.. https://doi.org/10.1097/00005344-199008000-00009

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