102. DO CHANGES IN LOCAL Ca CONCENTRATION AFFECT BLOOD FLOW IN THE BRAIN?
نویسنده
چکیده
The mechanism which links local changes in cerebral blood flow to neuronal activity is far from clear (Cameron, 1977, Clinical Science and Molecular Medicine, 52,549-554). Changes in the local concentration of H, K and adenosine may be respon sible. Recently, Nicholson et al. (1977, Proceedings of the National Academy of Sciences of the U.Sji., 74, 1287-1290) demonstrated that repetitive stimulation of neurons is accom panied by a fall in local [Ca]. Betz, Enzenross & Vlahov (1973, Pflügers Archiv, 343, 79-88) have shown that an increase in local [Ca] causes a constriction of pial arterioles and a reduction in dilatation. We have attempted to show that local changes within brain parenchyma will affect local flow and that changes in [Ca1 may be important, therefore, in the matching of blood flow to brain activity.
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تاریخ انتشار 2012