Target Sites for Anticholinesterases, Cholinolytics and Oximes on Ventral Medulla Oblongata
In recent years evidence has accumulated showing that many physiological functions including respiration, blood pressure, glucose regulation, vasopressin release may be greatly affected by chemical stimulation of selected sites on the ventral surface of medulla oblongata (reviews Feldberg 1976; Loeschcke 1980). It has also been shown that DFP (dy-flos) applied in these sites elicits a profound vasodepressor response resistant to atropine and accompanied with respiratory disturbances (Edery and Guertzenstein 1974). The studies have now been extended to the powerful organophosphate (o.p) soman (S). It will be shown that the anticholinesterase topically or systemically administered provoked a long lasting centrally originating hypotension which could be reversed by selective protection of ventromedully chemosensitive areas with antimuscarinic drugs and some particular oximes. These areas were found to contain muscarinic receptors and cholinesterase. Partial results have been presented (Edery 1978).
KeywordsMuscarinic Receptor Parietal Cortex Medulla Oblongata Cholinesterase Activity Hypotensive Response
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