OBJECTIVETo establish an artificial somatic-autonomic reflex arc in rats and observe the following distributive changes of neural fibers in the bladder.

METHODSAdult Sprague-Dawley rats were randomly divided into three groups: control group, spinal cord injury (SCI) group, and reinnervation group. DiI retrograde tracing was used to verify establishment of the model and to investigate the transport function of the regenerated efferent axons in the new reflex arc. Choline acetyltransferase (ChAT) in the DiI-labeled neurons was detected by immunohistochemistry. Distribution of neural fibers in the bladder was observed by acetylcholine esterase staining.

RESULTSDiI-labeled neurons distributed mainly in the left ventral horn from L3 to L5, and some of them were also ChAT-positive. The neural fibers in the bladder detrusor reduced remarkably in the SCI group compared with the control (P < 0.05). After establishment of the somatic-autonomic reflex arc in the reinnervation group, the number of ipsilateral fibers in the bladder increased markedly compared with the SCI group (P < 0.05), though still much less than that in the control (P < 0.05).

CONCLUSIONThe efferent branches of the somatic nerves may grow and replace the parasympathetic preganglionic axons through axonal regeneration. Acetylcholine is still the major neurotransmitter of the new reflex arc. The controllability of detrusor may be promoted when it is reinnervated by the pelvic ganglia efferent somatic motor fibers from the postganglionic axons.

Acetylcholinesterase ; biosynthesis ; Anastomosis, Surgical ; Animals ; Autonomic Fibers, Preganglionic ; physiology ; Cholinergic Fibers ; metabolism ; Immunohistochemistry ; Motor Neurons ; cytology ; metabolism ; Nerve Regeneration ; physiology ; Neural Pathways ; cytology ; metabolism ; Rats ; Rats, Sprague-Dawley ; Reflex ; physiology ; Spinal Cord Injuries ; physiopathology ; Spinal Nerve Roots ; surgery ; Urinary Bladder ; innervation ; physiology ; surgery ; Urinary Bladder, Neurogenic ; surgery

Effects of several autonomic drugs on the responses of the isolated rabbit detrusor muscle strips to electrical stimulation were investigated. Electric stimulation of the detrusor muscle strips elicited two different responses; (a) contraction followed by relaxation in 14 cases out of 22 experiments, and (b) contraction only in 8 cases. The contraction responses to electrical stimulation were significantly reduced in the presence of either atropine or regitine, respectively The relaxation response to electrical stimulation was abolished in the presence of propranolol. Addition of norepinephrine evoked one of following three responses: (a) relaxation in 10 cases out of 19 experiments, (b) contraction in 6 cases, and (c) contraction followed by relaxation in 4 cases. The relaxation response to norepinephrine was reversed. in the presence of propranolol, to a contraction response which was then abolished after administration of regitine. The contraction response to norepinephrine was reversed, in the presence of regitine, to a relaxation response which was then abolished after administration of propranolol. Acetylcholine elicited contraction of the isolated detrusor muscle strip, and this was abolished in the presence of atropine These results suggest that the rabbit detrusor muscle is innervated by both cholinergic and adrenergic fibers and that the detrusor muscle contains cholinergic receptors as well as adrenergic a-and b-ones. Contrary to the popular opinion that the detrusor muscle predominantly contains adrenergic b-receptors, it seems likely that the adrenergic receptors differ in predominancy of either a or b which elicits contraction or relaxation, respectively, according to different areas of the muscle.
Acetylcholine ; Adrenergic Fibers ; Atropine ; Autonomic Agents* ; Electric Stimulation* ; Norepinephrine ; Phentolamine ; Propranolol ; Receptors, Adrenergic ; Receptors, Cholinergic ; Relaxation

In this study the quantitative changes of the SP (senile plaque) and NFT (neurofibrillary tangle) in the intrinsic hippocampal neural circuit were analyzed. All patients (86 case) were diagnosed clinically and confirmed pathologically as Alzheimer disease. The results were: 1) The NET and SP were most prominenetly observed in the C/A1 region, but they were not so many in the CA2 and CA3 regions. 2) There were quantitative correlation between the NFT and the SP except in the presubiculum and the dentate fascia. 3) There were no significant rank correlation between the perikaryonic NFT and the terminal SP in the dentate fascia and the CA3 area. 4) There were significant statistic difference of the quantity of the NFT and the SP between each neighboring areas in the intrinsic hippocampal neural circuit. I think there could be some influences of cholinergic fiber that they were from the medial septal nuclei and the nuclei of the diagonal band to the dentate fascia and the CA3 area.
Alzheimer Disease* ; Cholinergic Fibers ; Dentate Gyrus ; Humans ; Neural Pathways* ; Septal Nuclei

To determine the peripheral mechanisms involved in thermal sweating during the hot summers in July before acclimatization and after acclimatization in September, we evaluated the sweating response of healthy subjects (n=10) to acetylcholine (ACh), a primary neurotransmitter involved in peripheral sudomotor sensitivity. The quantitative sudomotor axon reflex test (QSART) measures sympathetic C fiber function after iontophoresed ACh evokes a measurable reliable sweat response. The QSART, at 2 mA for 5 min with 10% ACh, was applied to determine the directly activated (DIR) and axon reflex-mediated (AXR) sweating responses during ACh iontophoresis. The AXR sweat onset-time by the axon reflex was 1.50+/-0.32 min and 1.84+/-0.46 min before acclimatization in July and after acclimatization in September, respectively (p<0.01). The sweat volume of the AXR(1) [during 5 min 10% iontophoresis] by the axon reflex was 1.45+/-0.53 mg/cm2 and 0.98+/-0.24 mg/cm2 before acclimatization in July and after acclimatization in September, respectively (p<0.001). The sweat volume of the AXR(2) [during 5 min post-iontophoresis] by the axon reflex was 2.06+/-0.24 mg/cm2 and 1.39+/-0.32 mg/cm2 before and after acclimatization in July and September, respectively (p<0.001). The sweat volume of the DIR was 5.88+/-1.33 mg/cm2 and 4.98+/-0.94 mg/cm2 before and after acclimatization in July and September, respectively (p<0.01). These findings suggest that lower peripheral sudomotor responses of the ACh receptors are indicative of a blunted sympathetic nerve response to ACh during exposure to hot summer weather conditions.
Acclimatization ; Acetylcholine ; Axons ; Hot Temperature ; Iontophoresis ; Nerve Fibers, Unmyelinated ; Neurotransmitter Agents ; Receptors, Cholinergic ; Reflex ; Sweat ; Sweating ; Weather

OBJECTIVETo investigate the changes of cholinergic nerves in doxorubicin (DOX)-induced rat failing heart and tumor necrosis factor-α (TNF-α) in the heart tissue and serum.

METHODSAdult Sprague-Dawley rats were randomized into control (n=10) and DOX-induced chronic heart failure (CHF) groups (n=15), and in the latter group, the rats were given intraperitoneal injections of 2.5 mg/kg DOX once a week for 6 weeks, with a total cumulative dose of 15 mg/kg. The control rats were injected with normal saline (1 ml/week). Karnovsky-Roots histochemical staining combined with point counting was used to demonstrate the distribution of cholinergic nerves in the heart. The expression levels of TNF-α in the heart tissue and serum were determined with ELISA.

RESULTSPositively stained cholinergic nerves were found in all the rat hearts in the two groups, but in CHF group, the point counts of cholinergic nerves were significantly lower than that of the control group (P<0.01). Compared with the control rats, those with DOX-induced CHF showed elevated levels of TNF-α both in the heart tissue and in the serum (P<0.01).

CONCLUSIONIn rats with DOX-induced CHF, the parasympathetic nervous system is down-regulated in the failing heart, and the diminished cholinergic anti-inflammatory pathway may play an important role in the progression of CHF.

Animals ; Cholinergic Agents ; pharmacology ; Cholinergic Fibers ; drug effects ; Doxorubicin ; pharmacology ; Heart ; drug effects ; innervation ; Heart Failure ; chemically induced ; metabolism ; Male ; Myocardium ; metabolism ; Rats ; Rats, Sprague-Dawley ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo investigate the effect of total fiavonoids from Chrysanthemun morifolium (TFCM) on learning and memory, and cholinergic system function in aging mice.

METHODSThe aging mice model was established by subcutaneous injection of D-galactose. ICR mice were divided into five groups (n=10): contrA group, model group, and TFCM groups. Mice in TFCM groups were given TFCM (50,100 or 150 mg/kg) by gastric irrigation once a day. Learning and memory ability were evaluated by Morris water maze test. The MDA content, SOD and Ach E activity were also measured.

RESULTSCompared with control group, learning and memory ability declined in the D-galactose-induced aging mice; meanwhile MDA content and AchE activity increased, SOD activity decreased. Treatment with TFCM (100, 150 mg/kg) ameliorated the decrease in learning and memory ability of aging mice. Compared with model group, TFCM (100, 150 mg/kg) could also decrease MDA content and Ach E activity, and increase SOD activity in aging mice.

CONCLUSIONTFCM may improve the learning and memory ability of aging mice. The mechanism is involved in its antioxidative characteristic and improvement of central cholinergic system function.

Aging ; drug effects ; physiology ; Animals ; Antioxidants ; pharmacology ; Cholinergic Fibers ; physiology ; Cholinergic Neurons ; physiology ; Chrysanthemum ; chemistry ; Female ; Flavonoids ; isolation & purification ; pharmacology ; Learning ; drug effects ; Male ; Memory ; drug effects ; Mice ; Mice, Inbred ICR

OBJECTIVETo investigate the relation between the progressive effects of chronic intermittent hypoxia (CIH) on cognitive function and the change of cholinergic neuron.

METHODSForty adult male Sprague-Dawley rats were randomly averagely divided into four groups: control group, CIH 1 week group, CIH 3 week group and CIH 5 week group. The cognitive function was assessed by the Morris Water Maze. The necrosis neurons in prefrontal cortex and hippocampus were observed and counted. The cholin acetyltransferase (ChAT) immunostained cells in prefrontal cortex and hippocampus were identified and quantitated.

RESULTSThe spatial learning and memory impairments progressed from 1 to 5 5 weeks in rats. Compared with the control group, the cognitive impairments in CIH5w group were significant (P < 0.05). The degeneration or necrosis neurons in prefrontal cortex and hippocampus were significantly increased in CIH rats, and worsen gradually along with the hypoxia. The ChAT immunostained cells in prefrontal cortex and hippocampus were gradually reduced. The ChAT immunostained cells of prefrontal cortex and hippocampus in CIH3w group and CIH5w group were less than that in control group (P < 0.05).

CONCLUSIONChronic intermittent hypoxia induced slowly progressive spatial learning and memory impairments in rats, which maybe associated with the damage of neurons and the reduction of ChAT in prefrontal cortex and hippocampus.

Animals ; Cholinergic Fibers ; pathology ; physiology ; Cholinergic Neurons ; pathology ; physiology ; Cognition ; physiology ; Hippocampus ; cytology ; physiopathology ; Hypoxia ; physiopathology ; Male ; Maze Learning ; physiology ; Memory Disorders ; etiology ; physiopathology ; Prefrontal Cortex ; cytology ; physiopathology ; Rats ; Rats, Sprague-Dawley

The hippocampus is a central area of the memory-related neural system. Combined immunohistochemistry against choline acetyl transferase and retrograde transneuronal labelling of the pseudorabies virus were used to identify cholinergic neurons in the central nervous system projecting to the hippocampal formation of the rat. Five to ten microL of Bartha strain of pseudorabies virus were injected into the dentate gyrus, CA1 and CA3 of the hippocampus of 20 Sprague Dawley rats using stereotaxic instrument. Forty eight to 96 hr after the injection, the brains were removed and the tissue sections were processed for double immunofluorescence procedure using polyclonal antibodies against pseudorabies virus or choline acetyl transferase. The double labelled neurons were distributed at several different nuclei and the labelling patterns of three different areas of the hippocampus were similar. These data suggests that the cholinergic innervation to the hippocampus were distributed in a transsynaptic manner throughout the whole brain area.
Animal ; Antibodies ; Choline O-Acetyltransferase/*analysis/immunology ; Cholinergic Fibers/*enzymology ; Herpesvirus 1, Suid/immunology ; Hippocampus/*cytology ; Immunohistochemistry ; Microinjections ; Neural Pathways ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the general pattern of cholinergic nerve distribution and M(2) receptors in adult rat heart.

METHODSKarnovsky-Roots histochemical staining combining point counting method and immunochemical SABC method with image analysis were used to identify the cholinergic nerves and M(2) receptors, respectively, in adult rat heart.

RESULTSPositive staining of cholinergic nerves and M(2) receptors was found in all regions of the rat heart, and the point count of cholinergic nerves in the atria was 4.6 times as much as that in ventricles, and the area of immunoreactive substance for M(2) receptors two-fold higher in the atria than in the ventricles. The point counts of the cholinergic nerves in the medial-layer myocardium were fewer than that in subepicardial and endocardial tissues of the left ventricular free wall. However, M(2) receptors were comparable among the 3 layers of the left free ventricular wall.

CONCLUSIONCholinergic nerves and M(2) receptors are located in both rat atria and ventricles, but their density is much higher in the atria than in the ventricles. Transmural heterogeneity characterizes cholinergic nerve innervation in the left ventricular free wall without significant differences in M(2) receptor density.

Animals ; Cholinergic Fibers ; metabolism ; Female ; Heart ; innervation ; Heart Atria ; innervation ; metabolism ; Heart Ventricles ; innervation ; metabolism ; Immunohistochemistry ; Male ; Myocardium ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptor, Muscarinic M2 ; analysis

BACKGROUND: Cholinergic neurons in the forebrain of mamals are well elucidated, meanwhile, the distribution of these neurons in the brainstem is not conformed according to investigators. To identify cholinergic neurons in the brainstem of CD rat, the authors performed immunohistochemical staining with monoclonal antibody to choline acetyltransferase(ChAT), the enzyme responsible for the biosynthesis of acetylcholine. METHODS: In order to decrease nonspecific reactions of the secondary antibody, an anti-rat IgG without biotin was pretreated before the primary antibody treatment. Blockage of the protein transport was tried to decrease the secretion of ChAT from neurons with colchicine injection into the lateral ventricle of the rat 36, to 48 hours before cardiac perfusion of fixative agent. RESULTS: Choline acetyltransferase immunoreactive neurons were identified in all motor nuclei of cranial nerves with some other nuclei and nerve fibers in rat brainstem. They were all multipolar cells mostly composed of magnocellular neurons, however parvocellular ones were also observed with colchicine pretreatment. CONCLUSION: Distribution of the ChAT-immunoreactive nuclei in the brainstem of the CD rats were found in the area where motor functions are closely involved. This means that acetylcholine is the neurotransmitter of these area composing brainstem motor center.
Acetylcholine ; Animals ; Biotin ; Brain Stem* ; Choline O-Acetyltransferase ; Choline* ; Cholinergic Neurons ; Colchicine ; Cranial Nerves ; Humans ; Immunoglobulin G ; Immunohistochemistry ; Lateral Ventricles ; Nerve Fibers ; Neurons ; Neurotransmitter Agents ; Perfusion ; Prosencephalon ; Protein Transport ; Rats* ; Research Personnel