Cholinergic stimulation

Vagotomy A surgical procedure that blocks vagal (cholinergic) stimulation to the stomach. 

Several of the postulated roles for nematode-secreted AChEs assume that they gain access to the intestinal mucosa. Several possibilities exist for transport of parasite AChE across the epithelial cell barrier, such as (i) utilization of existing pathways for receptor-mediated transcytosis (ii) a paracellular route facilitated by parasite-secreted proteases as observed for a bacterial elastase (Azghani et al., 1993) and (iii) increased paracellular permeability resulting from inflammatory events in the mucosa. We consider the latter suggestion most likely, as this has been duplicated by ex vivo perfusion with rat mast cell protease II (Scudamore et al., 1995). Moreover, cholinergic stimulation attenuates epithelial barrier properties to macromolecules in rat ileal crypts (Phillips et al., 1987). 

Phillips, T.E., Phillips, T.L. and Neutra, M.R. (1987) Macromolecules can pass through occluding junctions of rat ileal epithelium during cholinergic stimulation. Cell and Tissue Research 247, 547-554. 

Williams MB. Circadian variation in rat brain AP-1 DNA binding activity after cholinergic stimulation modulation by lithium. Psychopharmacology (Berlin), 1995 122 363-368. 

The rate of absorption from an SC injection site may be retarded by immobilization of the limb, local cooling to cause vasoconstriction, or application of a tourniquet proximal to the injection site to block the superficial venous drainage and lymphatic flow. In small amounts, adrenergic stimulants, such as epinephrine, will constrict the local blood vessels and, therefore, slow systemic absorption. Conversely, cholinergic stimulants (such as methacholine) will induce very rapid systemic absorption subcutaneously. Other agents may also alter their own rate of absorption by affecting local blood supply or capillary permeability. 

A dependency syndrome occurs in many who chew areca (Trivedy et al. 1999). This is not entirely suprising because other cholinergic stimulants (e.g., tobacco) also have addictive properties, and arecoline causes a release of dopamine like many other abused drugs. Use of areca persists despite adverse health effects—one of the criteria for addiction. 

Blaha CD, AUen EE, Das S, Inghs WE, Latimer MP, Vincent SR, Winn P (1996) Modulation of dopamine efflux in the nucleus accumbens after cholinergic stimulation of the ventral tegmental area in intact, pedunculopontine tegmental nucleus-lesioned, and laterodorsal tegmental nucleus-lesioned rats. J Neurosci 16 714-722... 

To avoid the undesirable effects of excess cholinergic stimulation, ACh is rapidly hydrolyzed after its release at the synapse by an enzyme named acetylcholinesterase AChE. A similar enzyme, butylcholinesterase BuChE also occurs. If the cholinesterase is inhibited, the ACh is not hydrolyzed so rapidly, and levels of ACh rise. 

The toxic effects of Calabar Bean extract were found to be due to excessive cholinergic stimulation giving rise to symptoms such as increased salivation, nausea, bradycardia, muscle cramps and respiratory failure, as well as CNS effects such as agitation. The cholinergic excess was found to be... 

Overdosage produces CNS stimulation, including insomnia, nervousness, and orthostatic hypotension, and cholinergic stimulation, such as headache, increased salivation and diaphoresis, nausea, vomiting, flushed skin, abdominal pain, and... 

Depressed patients, when compared with nondepressed control subjects, have been shown repeatedly to have an earlier occurrence of REM sleep onset induced by intravenous administration of cholinomimetics (M. Berger and Riemann 1993 Gillin et al. 1991 Riemann et al. 1994 Sitaram et al. 1980]. This well-established supersensitive response to cholinomimetics, however, also has been observed in schizophrenic patients (M. Berger and Riemann 1993 Riemann et al. 1991]. Yet, an increase in the density of rapid eye movements through cholinergic stimulation appears to be specific to depression [Riemann et al. 1994]. 

Kennedy ED, Challiss RJ, Nahorski SR Lithium reduces the accumulation of inositol polyphosphate second messengers following cholinergic stimulation of cerebral cortex slices. J Neurochem 53 1652-1655, 1989... 

Aihaara T et al Cholinergically stimulated gastric acid secretion is mediated by M3 and M5 but not Mi muscarinic acetylcholine receptors in mice. Am J Physiol 2005 288 G1199. 

Uses antidote for excessive cholinergic stimulation tremor treatment wide angle glaucoma stomach disorders preanesthesia Arco-Lase Plus -mixture of enzymes, hyoscyamine, atropine, and phenobarbital Donnatal -hyoscyamine, atropine, scopolamine, and phenobarbital... 

The toxic effect of all the above compounds begins to be manifested within 1—5 min. In lethal cases all animals die within 15 minutes. Bennett thinks that the toxic effect of 1-phenylsilatrane and its derivatives is due to central cholinergic stimulation. 

Bado, A., Laigneau, J.P., Moizo, L., Cherifi, Y., Lewin, M.J.M., 1995. H3-receptor activation inhibits cholinergic stimulation of acid secretion in isolated rabbit fiindic glands. J. Pharmacol. Exp. Ther. 275, 1099-1103. 

Cholinergic facilitation—e.g., postganglionic cholinergic stimulants, such as acetylcholine, other choline derivatives, and pilocarpine. 

Krane C M, Fortner C N, Hand A R, McGraw D W, Lorenz J N, Wert S E, Townee J E, Paul R J, Whitsett J A, Menon A G. 2001. Aquaporin5-deficient mouse lungs are hyperresponsive to cholinergic stimulation. Proc Natl Acad Sci USA 98 14114-14119. 

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