Search results for "Physostigmine"
showing 2 items of 22 documents
Release of non-neuronal acetylcholine from the human placenta: difference to neuronal acetylcholine
2001
The synthesis and release of non-neuronal acetylcholine, a widely expressed signaling molecule, were investigated in the human placenta. This tissue is free of cholinergic neurons, i.e. a contamination of neuronal acetylcholine can be excluded. The villus showed a choline acetyltransferase (ChAT) activity of 0.65 nmol/mg protein per h and contained 500 nmol acetylcholine/g dry weight. In the absence of cholinesterase inhibitors the release of acetylcholine from isolated villus pieces amounted to 1.3 nmol/g wet weight per 10 min corresponding to a fractional release rate of 0.13% per min. The following substances did not significantly modify the release of acetylcholine: oxotremorine (1 micr…
Acetylcholine overflow during infusion of a high potassium-low sodium solution into the perfused chicken heart in the absence and presence of physost…
1977
1. The effect of infusion of a modified Tyrode's solution (“high K+-low Na+ solution”) into the isolated chicken heart on the content of acetylcholine in the tissue and the overflow of acetylcholine were compared to those evoked by vagal stimulation. 2. The release of acetylcholine was measured over 15-min periods of either stimulation of the vagus nerves (40 V, 1 ms) at 20 Hz or of infusion of the high K+-low Na+ solution (108 mM K+, 44 mM Na+). 3. Both stimuli caused a maximum overflow of acetylcholine in the first few minutes whether or not 10−6 M physostigmine was present. The overflow was maintained during the vagal stimulation at a constant rate of at least 35% the initial rate, where…