Am J Physiol Gastrointest Liver Physiol
February 2009
Impaired gastric accommodation and gastric dysrhythmia are common in gastroparesis and functional dyspepsia. Recent studies have shown that synchronized gastric electrical stimulation (SGES) accelerates gastric emptying and enhances antral contractions in dogs. The aim of this study was to investigate the effects and mechanism of SGES on gastric accommodation and slow waves impaired by vagotomy in dogs.
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September 2008
Rectal distension (RD) is known to induce upper gastrointestinal (GI) symptoms. The aim of this study was to investigate the effects and underlying mechanisms of RD on gastric slow waves (GSW) and motor activity and furthermore to investigate the effects and mechanisms of electroacupuncture (EA) on GSW and motor activity. Eight female hound dogs chronically implanted with gastric serosal electrodes and a gastric fistula were studied in six separate sessions.
View Article and Find Full Text PDFThe Alzheimer's amyloid protein (Abeta) is released from the larger amyloid beta-protein precursor (APP) by unidentified enzymes referred to as beta- and gamma-secretase. beta-Secretase cleaves APP on the amino side of Abeta producing a large secreted derivative (sAPPbeta) and an Abeta-bearing C-terminal derivative that is subsequently cleaved by gamma-secretase to release Abeta. Alternative cleavage of the APP by alpha-secretase at Abeta16/17 releases the secreted derivative sAPPalpha.
View Article and Find Full Text PDFCalcium-evoked dendritic exocytosis (CEDE), demonstrated in cultured hippocampal neurons, is a novel mechanism that could play a role in synaptic plasticity. A number of forms of neuronal plasticity are thought to be mediated by calcium/calmodulin-dependent protein kinase II (CaMKII). Here, we investigate the role of CaMKII in CEDE.
View Article and Find Full Text PDFHere we describe a technique that uses a recombinant vaccinia virus to transfect neurons in rat hippocampal slices. This technique allows the use of molecular biological manipulations on neuronal tissue while maintaining intact synaptic function. This method should be useful in testing specific hypotheses regarding the role of synaptic proteins.
View Article and Find Full Text PDFVaccinia virus can be used to infect cells in the CNS of frogs, Xenopus laevis, and Rana pipiens, both in vivo and in vitro. In vivo infections were accomplished by injection of viral solution into the tectal ventricle of stage 40-48 tadpoles or by local injections into distinct neural regions. Infections with high titer of virus injected into the ventricle resulted in the majority of cells in the brain expressing foreign protein, while cells in the retina and optic nerve showed no expression.
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