Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.1.7 (acetylcholinesterase)
 28,390 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adult male Long-Evans rats were intermittently exposed to 2450 MHz CW microwaves at an average power density of 0.5 mW/cm2 for 90 days. The resulting SAR was 0.14 W/kg (range 0.11 to 0.18 W/kg). The animals were exposed 7 h/day, 7 days/wk, for a total of 630 h in a monopole-above-ground radiation chamber while housed in Plexiglas holding cages. Daily measures of body mass and food and water intake indicated no statistically significant effects of microwave exposure. Monthly assessment of reactivity to electric footshock, levels of cholinesterase and sulfhydryl groups in blood, and 17-ketosteroids in urine revealed no reliable differences between 14 sham-exposed and 14 microwave-exposed rats. After the 90 days of exposure, seven rats, randomly chosen from each group, were assessed for open-field behavior, shuttlebox performance, and schedule-controlled (IRT schedule) lever pressing for food pellets. Statistically significant differences between microwave-exposed and sham-exposed rats were observed in shuttlebox performances and lever pressing. Post mortem measures of mass of several organs and microscopic examination of adrenal tissue revealed no differences between the two groups of animals.
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PMID:Behavioral and physiological effects of chronic 2,450-MHz microwave irradiation of the rat at 0.5 mW/cm2. 373 1

The ascending cholinergic projections of the pedunculopontine and dorsolateral tegmental nuclei, referred to collectively as the pontomesencephalotegmental (PMT) cholinergic complex, were investigated by use of fluorescent tracer histology in combination with choline-O-acetyltransferase (ChAT) immunohistochemistry and acetylcholinesterase (AChE) pharmacohistochemistry. Propidium iodide, true blue, or Evans blue was infused into the anterior, reticular, mediodorsal, central medial, and posterior nuclear areas of the thalamus; the habenula; lateral geniculate; superior colliculus; pretectal/parafascicular area; subthalamic nucleus; caudate-putamen complex; globus pallidus; entopeduncular nucleus; substantia nigra; medial septal nucleus/vertical limb of the diagonal band area; magnocellular preoptic/ventral pallidal area; and lateral hypothalamus. In some animals, separate injections of propidium iodide and true blue were made into two different regions in the same rat brain, usually a dorsal and a ventral target, in order to assess collateralization patterns. Retrogradely transported fluorescent labels and ChAT and/or AChE were analyzed microscopically on the same brain section. All of the above-delimited targets were found to receive cholinergic input from the PMT cholinergic complex, but some regions were preferentially innervated by either the pedunculopontine or dorsolateral tegmental nucleus. The former subdivision of the PMT cholinergic complex projected selectively to extrapyramidal structures and the superior colliculus, whereas the dorsolateral tegmental nucleus was observed to provide cholinergic input preferentially to anterior thalamic regions and rostral portions of the basal forebrain. The PMT cholinergic neurons showed a tendency to collateralize extensively.
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PMID:Cholinergic systems in the rat brain: III. Projections from the pontomesencephalic tegmentum to the thalamus, tectum, basal ganglia, and basal forebrain. 374 47

Long-Evans male adult rats were intermittently exposed for 14 weeks to continuous wave (CW) 2450-MHz microwaves at an average power density of 2.5 mW/cm2. The mean specific absorption rate was 0.70 W/kg (+/- 0.02 SEM). The rats were exposed 7 h/day, 7 days/week in a radiation chamber with a monopole above ground, while housed in Plexiglas cages. Weekly measures of body mass and food intake did not indicate statistically significant effects of microwave irradiation. Assessments of threshold for electric-footshock detection revealed a significant difference between microwave and sham-exposed animals. Assessments of cholinesterase and sulfhydryl groups in blood and 17-ketosteroids in urine did not distinguish the two groups of rats. Behavioral measures made at the end of the 14-week exposure included an open-field test, shuttlebox avoidance performance, and schedule-controlled lever-pressing for food pellets. Statistically significant differences between microwave- and sham-exposed rats were observed for these measures. Examination of adrenal tissue, plasma electrolytes, and organ masses after 14 weeks of exposure revealed no difference between the two groups of rats.
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PMID:Intermittent exposure of rats to 2450 MHz microwaves at 2.5 mW cm2: behavioral and physiological effects. 375 34

This report describes the distribution of histochemically identified 'non-specific' cholinesterase (ChE)-containing neurons in the dorsal thalamus of the rat. Juvenile or young adult Long-Evans or Sprague-Dawley rats were sacrificed by formalin perfusion. Some animals received systemic injections of 1.5-2.0 mg/kg DFP 4-24 h prior to sacrifice. Separate series of 50 micron frozen sections were processed for cholinesterase histochemistry using acetylthiocholine, butyrylthiocholine, or propionylthiocholine as substrates. Adjacent sections processed with each of the 3 substrates allowed comparison of the distributions of neurons containing the histochemical reaction products. Neurons containing moderate to high concentrations of ChE reaction product were found in 3 distinct regions of the dorsal thalamus. First, neurons staining intensely for ChE were found in a cluster that corresponds to the thalamic reuniens nucleus. Second, a cluster of neurons staining intensely for ChE was found in a region that included the lateral part of the central lateral nucleus and extended laterally into the ventral-lateral part of the lateral dorsal nucleus. Third, moderate ChE staining was observed in the neurons of the anterior dorsal nucleus. Of these regions, only the anterior dorsal nucleus shows moderate to high levels of acetylcholinesterase. The function of ChE in normal brain function is unknown. It is particularly interesting, however, that the thalamic nuclei containing ChE-positive neurons send thalamocortical projections to the medial limbic cortex, including cingulate, retrosplenial and subicular cortices.
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PMID:Distribution of 'non-specific' cholinesterase-containing neurons in the dorsal thalamus of the rat. 395 49

The putative neurotoxicity of the organophosphorus compound triphenyl phosphite (TPP) was examined in Long Evans, adult male rats. Animals were exposed to two 1.0 ml/kg (1184 mg/kg) injections (sc) of TPP spaced 1 week apart and sampled for biochemical and neuropathological examination. At the time of sampling, rats displayed dysfunctional changes including tail rigidity, circling, and hindlimb paralysis. Neuropathic damage was confined to the lateral and ventral columns of all spinal levels and consisted of myelin ellipsoids and giant axonal swellings filled with smooth endoplasmic reticulum. Wallerian-like degeneration was observed in the spinal roots, the sciatic nerve, and tibial branches. Biochemical assessment of brain acetylcholinesterase (AChE) and neurotoxic esterase (NTE) activity was determined 1, 4, 24, 48, and 72 hr after the second TPP treatment. Both enzyme activity concentrations were depressed maximally at 48 hr postexposure by 30 and 39%, respectively. Serum cholinesterase, sampled 48 hr after the second TPP exposure was depressed by 33%. Data from this study indicate that subchronic exposure to the organophosphite TPP results in severe neurotoxic consequences which differ from those previously described in rats with organophosphorus-induced delayed neuropathy.
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PMID:Biochemical and neuropathological assessment of triphenyl phosphite in rats. 396 10

This paper describes the normal development and disappearance of acetylcholinesterase (AChE) activity in layer IV of rat visual cortex and the effects of neonatal monocular enucleation on this transient pattern of AChE activity. Subjects were laboratory-born male or female Long-Evans rats. Some animals underwent monocular enucleation within 6 h of birth. Animals were sacrificed at various ages and AChE activity was detected histochemically in tissue sections. AChE activity is first detectable histochemically in visual cortex area 17 as a fine fiber-like plexus in layer IV at about 7 postnatal days of age. The intensity of the staining increases during the second postnatal week and reaches peak intensity at days 12-14. The intensity of the AChE staining in layer IV of area 17 appears to decrease during the third postnatal week and the dense AChE band disappears by postnatal day 21. The distribution of AChE in layer IV of area 17 corresponds closely to the field of termination of geniculocortical projections and the fiber-like pattern of AChE activity resembles the appearance of an axonal terminal field. Neonatal monocular enucleation results in a marked decrement in the spatial extent of the AChE activity in layer IV of cortical area 17. The AChE-positive plexus is lost in the medial regions of area 17 contralateral to the enucleated eye. AChE activity remains in the lateral part of area 17, probably corresponding to that part of area 17 innervated by secondary projections from the intact ipsilateral eye. The functional role of this transient AChE activity is unknown. The present data suggest that AChE activity is characteristic of geniculocortical axon terminals during the period of time in which they are establishing functional connections with postsynaptic sites in cortex.
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PMID:Transient patterns of acetylcholinesterase activity in visual cortex of the rat: normal development and the effects of neonatal monocular enucleation. 404 4

The catecholaminergic innervation of three recently described dendrite bundles (midline, central and lateral) in the cervical spinal cord of the adult Long-Evans hooded rat [41] was examined using Golgi impregnation, fluorescence histochemistry for catecholamines, and cholinesterase histochemistry. The midline and lateral bundles were similar in appearance to those described by the Scheibel and Scheibel [50,51], while the central bundle, present in the region of the phrenic nucleus, has not been described previously. Analysis of Golgi-Cox impregnated horizontal sections demonstrated the presence of fine varicose fibers within all three bundles. These profiles entered the bundles at right angles, either singly or within small transverse dendritic subunits, then turned in a rostral or caudal direction, and coursed adjacent to dendrites of motoneurons in the bundles. Catecholamine histofluorescence in horizontal sections revealed abundant varicosities within all three bundles, similar in size and appearance to the varicose fibers seen in Golgi-Cox impregnated sections. Catecholamine fibers entered the dendrite bundles at right angles then turned rostrally or caudally and coursed horizontally within the bundles. Varicose fluorescent profiles formed pericellular rings around the motoneurons and linear profiles adjacent to the dendrites, sometimes outlining the entire proximal portion of primary dendrites. Catecholamine fibers entered the dendrite bundles at right angles then turned rostrally or caudally to course adjacent to the dendrites within the bundles. Cholinesterase histochemistry in alternate sections revealed staining of motoneurons and their dendrites, and confirmed the location of the catecholamine varicosities within the motoneuron dendrite bundles.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Catecholamine innervation of cervical dendrite bundles: possible phrenic nucleus innervation. 653 16

A review of previous evidence suggested the possibility of a functional association between the effects of early lead (Pb) exposure, hippocampal damage and cholinergic deficiency. To further assess this possibility, Long-Evans hooded rat pups were exposed to Pb for the first 25 postnatal days via the maternal milk. Dams were fed either 4.0% PbCO3 or a Na2CO3 control diet throughout this period. At 30 and 115 days of age, the brains of Pb and control animals were processed for acetylcholinesterase histochemistry. Morphometric evaluation of the molecular layer of the hippocampal dentate gyrus indicated that while absolute increases in the dimensions of the afferent systems to the hippocampal dentate gyrus are observed between 30 and 115 days of age, no significant rearrangement in the pattern of lamination occurs during this time. No effects of Pb were seen on the development of the cholinergic innervation of this brain region at either of these ages. Unilateral perforant path transections performed on Pb and control animals at 100 days of age indicated reduced cholinergic plasticity in the molecular layer of the hippocampal dentate gyrus of Pb exposed animals, as indicated by AChE histochemistry. These findings indicate that a decrease in neuroanatomical plasticity may be a critical brain mechanism underlying the learning deficits observed following exposure to Pb.
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PMID:Development and plasticity of the hippocampal-cholinergic system in normal and early lead exposed rats. 668 78

Retrograde transport of Evans blue dye from the rat dentate gyrus was used to identify afferent hypothalamic cells. Photography of the fluorescent hypothalamic cells was followed by incubation in an acetylthiocholine medium. Slides were re-photographed for acetylcholinesterase-induced reaction product. Nearly all posterior hypothalamic cell afferents to the dentate gyrus could be positively identified as containing acetylcholinesterase.
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PMID:Hypothalamic afferents to the dorsal dentate gyrus contain acetylcholinesterase. 688 2

The retrograde fluorescent tracing technique was combined with the di-isopropylfluorophosphate (DFP) histochemical procedure for acetylcholinesterase (AChE). Three fluorescent tracers (True blue, Fast blue and Evans blue) were injected into the rat striatum. After the appropriate survival time and after the administration of DFP, AChE reaction products could be observed in the fluorescent retrogradely labeled substantia nigra neurons. The fluorescent retrograde labeling and AChE brown reaction products were observed in the same cell bodies by simply turning on and off the bright-field illumination while observing with fluorescence. The sensitivity of the method appeared to be related to the length of the survival time after the tracer injection as well as after the DFP administration. This combined method allows to study the efferent connections of AChE-containing neurons in the central nervous system.
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PMID:Retrograde fluorescent neuronal tracing combined with acetylcholinesterase histochemistry. 712 Oct 56


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