AIM To find if tacrine exerts a sensitizing effect on the cholinergic receptors of gastric smooth muscles, and study some of the mechanisms inducing it and measure the relative intensity of tacrine's effects on contractile activity. MATERIAL AND METHODS Isometric recording of the mechanical activity of gastric smooth muscle preparations; determination of acetyl-cholinesterase activity in smoo...

Inhibition of acetylcholinesterase (AChE) is regarded as the primary toxic mechanism of organophosphorus compounds (OP). Therapeutic strategies are directed to antagonise overstimulation of muscarinic receptors with atropine and to reactivate inhibited AChE with oximes. Reactivation is crucial within the neuromuscular synapse, where atropine is ineffective, since peripheral neuromuscular block ...

Human serum cholinesterase was digested with pepsin under conditions which left disulfide bonds intact. Peptides were isolated by high pressure liquid chromatography, and those containing disulfide bonds were identified by a color assay. Peptides were characterized by amino acid sequencing and composition analysis. Human serum cholinesterase contains 8 half-cystines in each subunit of 574 amino...

A cholinesterase was purified 36-fold from mung bean (Phaseolus aureus) roots by a combination of differential extraction media and gel filtration. The enzyme could be effectively extracted only by high salt concentration, indicating that it is probably membrane-bound. Methods used for assaying animal cholinesterases were tested, two of which were adapted for use with the bean cholinesterase. T...

the crude methanolic extract of the seeds of celastrus paniculatus along with its organic soluble fractions were tested for their possible antioxidant and anti-alzheirmer (ad) activity. the extracts showed prominent dpph free radical scavenging activity, inhibiting activity of authentic peroxynitrite (onoo-) and inhibition of total reactive oxygen species (ros) generation. in dpph radical scave...

background: treatment of chronic constipation is creating one of the major problems for doctors and patients. pyridostigmine increases the gastrointestinal motility through the effects on cholinesterase. it seems that this mechanism can reduce chronic constipation. the aim of this study was to compare the effects of pyridostigmine and bisacodyl on chronic constipation. methods: this study was c...

Patients with Alzheimer's disease after an initial response to cholinesterase inhibitors may complain a later lack of efficacy. This, in association with incident neuropsychiatric symptoms, may worsen patient quality of life. Thus, the switch to another cholinesterase inhibitor could represent a valid therapeutic strategy. The aim of this study was to investigate the effectiveness of the switch...

This study concerns the distribution of cholinesterases in human skin. Previous work on this subject was published last year by Hurley, Shelley and Koelle (1) These authors used a method originated by Koelle (2, 3). In Koelle's method, acetyithiocholine and butyryithiocholine are used as substrates. It is assumed that acetyithiocholine is split by specific acetyicholinesterase as well as by non...

OBJECTIVE Agricultural pesticide handlers are at an elevated risk for overexposure to organophosphate (OP) pesticides, but symptoms can be difficult to recognise, making biomarkers invaluable for diagnosis. Occupational monitoring programmes for cholinesterase depression generally rely on measuring activity of either of the two common blood cholinesterases which serve as proxy measurements for ...

Most investigations of possible metabolic aberrations in childhood schizophrenia failed to demonstrate differences between schizophrenic patients and control groups. Cholinesterase activity has net been previously reported in schizophrenic children. Similar studies with adult schizophrenics have hot been consistent, despite some reports of abnormal cholinesterase activity. The present study rep...