Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The spontaneously epileptic rat (SER), a mutant homozygous for both zitter and tremor genes, exhibits absence-like seizures and tonic convulsions without external stimulation from 7 to 8 weeks of age. Histopathological studies of the central nervous system revealed the following abnormalities. The 35-day-old SERs which exhibit body tremor, and which have never shown seizures, had marked vacuolation and hypomyelination in the brainstem and cerebellum. The vacuoles were produced by splitting of the myelin sheaths and swelling of the dendrites and were related to primary swelling of the astrocytes. The 2- to 3-month-old SERs with staggering gait and seizures showed focal axonal swelling ('torpedo') and advanced vacuolation in the granular cell layer of the cerebellum in addition to the abnormalities observed at 35 days of age. Degenerative neurons and spheroidal bodies were observed in the substantia nigra and ventral tegmental nucleus. These brain areas are known to be related to tonic convulsions in the several experimental models. The SER is believed to be a useful tool for the investigation of the relationship between the structure and function of the central nervous system in epilepsy. It is probable that the more severe changes in the cerebellum are responsible for the staggering gait.
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PMID:The spontaneously epileptic rat (SER), a zitter*tremor double mutant rat: histopathological findings in the central nervous system. 237 85

Hyperbaric pressure induces hyperexcitability, tremor, and convulsions in intact animals by mechanisms that are not understood. High pressure induces spontaneous electrical discharges in the spinal ventral roots which we call "tremor-associated activity" (TAA). This study examined the nature of TAA, its likely origins, and its possible contribution in the cervical roots to respiratory difficulties. Activity was recorded extracellularly from the cut cervical ventral roots C1 and C5 in an in vitro brainstem-spinal cord preparation from newborn rats. Under hyperbaric conditions spontaneous TAA was observed either between the typical respiratory bursts in C1 and C5 or immediately after the burst itself. Stimulating the trigeminal nerve at 1 Hz induced a direct excitatory medullospinal reflex which, at high pressure, was followed by a conspicuous TAA. The TAA evoked by the dorsoventral root reflex in isolated spinal cord under hyperbaric conditions was similar to that evoked by the medullospinal reflex. These findings suggest that basic TAA originates at the level of the spinal cord and may be triggered by various synaptic inputs. They further suggest that pressure-induced abnormal activity of the motoneuron pool innervating various respiratory muscles may contribute to respiratory problems encountered under hyperbaric conditions.
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PMID:Pressure-induced tremor-associated activity in ventral roots in isolated spinal cord of newborn rats. 239 30

Repeated application of hexachlorocyclohexane (HCH; 50 and 100 mg/kg) and malathion (200 and 400 mg/kg) alone or in combination daily for 30 days on the skin of male guinea pigs caused mild to severe signs of toxicity and death of animals. The experimental animals exhibited tremor, dyspnea, salivation, convulsion, diarrhea and paralysis of the limbs. These were associated with significant biochemical and morphological changes in skin, liver, kidney and testes. The inhibition of acetylcholinesterase appeared highly significant in the combined treatment, but was not suggestive of any HCH and malathion potentiation. The highest level of HCH residue was seen in fatty tissue after low dose treatment. This was in contrast to the high level seen in liver after larger doses of HCH. This study suggests that HCH and malathion did not elicit any potentiation effects in the parameters monitored and at the doses tested.
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PMID:Interaction of hexachlorocyclohexane and malathion in male guinea pigs after repeated dermal application. 243 88

Myelin deficiency (mld) is an autosomal recessive mutation in mice and is considered to be allelic to the shiverer (shi) mutation. Mld mice are characterized by hypomyelination of the central nervous system (CNS). They show typical symptoms such as tremor, tonic convulsion and ataxic movement. Subcellular fractionation of the CNS revealed that the MBP bands were greatly decreased in the P2A (myelin) fraction and the total content of myelin basic protein (MBP) was much lower than that in the control in all parts of the CNS. Sections from mld mice were examined by immunohistochemical tests with MBP antiserum, and a mosaic expression of MBP was found in the myelin of the mld mice. Since the major dense line is considered to be composed mainly of MBP, we investigated the myelin of mld mice by electron microscopy and found that there were 3 types of myelin: (1) a normal type compact myelin with a major dense line, (2) a shiverer-type myelin with no major dense line, and (3) a mixed-type myelin, in which within a myelin lamella the major dense line abruptly changes to cytoplasm of oligodendrocytes.
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PMID:Immunohistochemical, biochemical and electron microscopic analysis of myelin formation in the central nervous system of myelin deficient (mld) mutant mice. 244 19

A prospective study of symptomatic hypoglycaemia was conducted in 47 children over a 14-week period using a questionnaire completed at home for each episode of hypoglycaemia. Twenty-nine children (62%) experienced 150 episodes during the study. The average incidence was once every 33 days (range 0-5.2 mo-1). Hypoglycaemia occurred more frequently in children with lowest haemoglobin A1 levels. Episodes were not randomly distributed in time; hypoglycaemia occurred significantly more frequently in the evening, in the early morning and around midday. The majority of episodes were judged to be mild but 2 children had nocturnal convulsions and glucagon was used on three occasions. Symptomatic nocturnal hypoglycaemia occurred one or more times in 30% of the children. Daytime episodes were manifested by tremor, feeling weak, dizziness, pallor, and other symptoms and signs. In 46% of cases the cause was not evident to parents or children, but 25% were related to physical activity.
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PMID:A prospective study of symptomatic hypoglycaemia in childhood diabetes. 252 5

The behavioral effects of paroxetine were investigated in mice and rats in comparison with imipramine and amitriptyline. 1) Locomotor activities were decreased by imipramine and amitriptyline but not by paroxetine in both animal species. 2) Paroxetine antagonized methamphetamine-induced hyperactivity in mice as did imipramine and amitriptyline. 3) Paroxetine showed a more potent antimuricidal effect in raphe-lesioned rats than imipramine and amitriptyline, and it also inhibited muricide in olfactory bulbectomized rats. 4) The immobility of rats in the forced swimming test was markedly decreased by imipramine and amitriptyline, but only slightly by paroxetine. 5) Like imipramine and amitriptyline, paroxetine potentiated the methamphetamine- or L-DOPA-induced stereotyped sniffing, and it inhibited oxotremorine-induced tremor. 6) Paroxetine antagonized reserpine-induced hypothermia, tetrabenazine-induced ptosis, and enhanced ether-induced anesthesia, all less potently than imipramine and amitriptyline. 7) The analgesic action of paroxetine was stronger than that of imipramine and amitriptyline. 8) Paroxetine did not antagonize maximal electroshock- or pentetrazol-induced convulsions and haloperidol- or THC-induced catalepsy in rats. In addition, paroxetine neither exerted muscle relaxation nor affected the shuttle-box type conditioned avoidance in rats. From these results, the behavioral effects of paroxetine, as compared with imipramine and amitriptyline, were characterized by its potent antimuricidal action in raphe-lesioned rats and its weak effect in the forced swimming test and by its less potent muscle relaxant, anticonvulsant, anticataleptic and anesthesia-potentiating actions.
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PMID:[Behavioral pharmacological properties of the novel antidepressant paroxetine, a selective 5-HT uptake inhibitor]. 253 Jan 42

The high pressure neurological syndrome (HPNS) occurs when man or animals are exposed to hyperbaric pressure. Four non-competitive N-methyl-D-aspartate (NMDA) antagonists - MK-801, phencyclidine (PCP), SKF 10,047 and ketamine were tested in rats for effects on the HPNS. All drugs were injected i.p. prior to compression; ketamine was also infused i.v. Control rats received saline. Rats were exposed individually to increasing helium pressure (PO2 0.5 atmospheres absolute ATA). Three endpoints were used to assess HPNS: onset pressures for tremor, myoclonus and convulsions. Neither MK-801 (0.03 and 0.3 mg/kg) nor SKF 10,047 (50 mg/kg) had any effect on the onset pressures for tremor, myoclonus or convulsions, although the type of seizure was modified from the clonic/tonic seizure seen in controls to purely clonic. PCP (5 mg/kg) had no effect on the endpoints, but pressure enhanced the excitation and stereotypy seen at 1 ATA. Ketamine (100 mg/kg i.p.) did not affect tremor or myoclonus; ketamine infused i.v. at pressure only prevented tremor and myoclonus at 'anaesthetizing' concentrations. Our results show that these non-competitive NMDA antagonists had little effect on HPNS, in contrast to competitive NMDA antagonists, such as AP7, which are highly effective. Possible explanations for this lack of effect include (1) interactions with NMDA receptor channels are pressure dependent; (2) other actions of these antagonists override their effects on the NMDA receptor channel.
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PMID:The effects of non-competitive NMDA receptor antagonists on rats exposed to hyperbaric pressure. 254 78

Rat pups were injected intracisternally (i.c.) or intraperitoneally (i.p.) with 5,7-dihydroxytryptamine (5,7-DHT) or saline and challenged 2 and 14 weeks later with the 5-HT precursor 5-hydroxytryptophan (5-HTP), which evokes behavioral supersensitivity in adult rats, 5,7-DHT induced transient postinjection convulsions in rats injected i.c. but not i.p. Rats with either type of 5,7-DHT lesions displayed supersensitive behavioral responses to 5-HTP. However, rats lesioned by i.p. injections exhibited significantly greater shaking behavior (+1445%) in response to 5-HTP than their i.c. counterparts, who instead showed more forepaw myoclonus (+250%) and head weaving (+270%), the core features of the 5-HT syndrome. Differences in 5-HT syndrome behaviors were already present 2 weeks after lesioning, whereas the difference in shaking behavior was not. After 14 weeks, 5-HT was selectively depleted (-43 to -92%) in hippocampus, spinal cord, and frontal cortex, and differences between i.c. and i.p. 5,7-DHT routes were insignificant except in frontal cortex. Brainstem 5-HT concentrations were significantly increased (+35%) after i.p. 5,7-DHT injections in contrast to reduction (-89%) after i.c. 5,7-DHT; 5-hydroxyindole acetic acid/5-hydroxytryptamine (5-HIAA/5-HT) ratios were decreased (-20%) with either route. These data suggest that brainstem 5-HT hyperinnervation following i.p. 5,7-DHT injection modifies the functional consequences of injury in abating the 5-HT syndrome, but does not result in complete recovery since shaking behavior is enhanced. Loss of presynaptically mediated autoregulation or receptor dysregulation may play a major role in behavioral supersensitivity induced by 5-HTP in rats with 5,7-DHT lesions. To the extent that the 5-HT syndrome is mediated by 5-HT1A receptors and shaking behavior by 5-HT2 sites, differential responses to injury of 5-HT1A and 5-HT2 receptors may contribute to these behavioral differences.
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PMID:Brainstem serotonergic hyperinnervation modifies behavioral supersensitivity to 5-hydroxytryptophan in the rat. 258 10

Acute toxicity studies of propiverine hydrochloride (P-4) were carried out in mice, rats and dogs of both sexes. 1. The LD50 values of P-4 were as follows: Mice; 410 (male) and 323 (female) mg/kg in oral route, 223 (male) and 283 (female) mg/kg in subcutaneous route and 36 (male and female) mg/kg in intravenous route, Rats; 1000 (male) and 1092 (female) mg/kg in oral route, 1632 (male) and 1411 (female) mg/kg in subcutaneous route, and 22 (male) and 25 (female) mg/kg in intravenous route. On the LD50 values, no sexual difference was apparent but the species difference between mice and rats observed to be present in oral and subcutaneous routes. The approximate lethal doses of P-4 in dogs were 987-1137 mg/kg for male and 865-894 mg/kg for female in oral route, and the values were almost same as those in rats of oral route. 2. Major toxic signs such as clonic convulsion, bradypnoea, dyspnoea, decreased spontaneous activity and hematuria were observed in mice and rats. Furthermore mydriasis in rats, and transitory salivation and/or vocalization in mice and rats were observed. In some rats, sedation, salivation, soil at hypogastrium, rale and emaciation were detected from the next day of oral administration. In dogs, toxic signs such as vomiting, tremor, tonic and/or clonic convulsion, mydriasis and gasping were observed. 3. Pathological changes observed in dead animals were congestion of lungs, liver and kidneys in all routes, congestion and hemorrhage in digestive tracts in oral route, inflammatory changes at the injection site in subcutaneous route. In addition, retention of hematuria in urinary bladder in rats of oral and subcutaneous routes, the hemorrhagic changes of heart, atonia of urinary bladder and retention of urine in dogs were observed. 4. The main cause of death seemed to be respiratory disturbance in all species and the weakness in a few rats of oral route.
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PMID:[Acute toxicity studies of propiverine hydrochloride]. 260 50

Acute toxicity studies of miporamicin and its trace ingredients, degradations and metabolites were conducted in mice and rats. 1. Following oral administration of miporamicin (MPM), none died among mice or rats even at the highest dosage levels. Therefore, its LD50 values were estimated to be greater than 2,500 mg/kg for mice and greater than 2,000 mg/kg for rats. The LD50 value of MPM was the highest by oral route, followed, in order, by subcutaneous route and intravenous route. There was no difference in this respect between sexes of animals studied. 2. No signs of abnormalities were observed among mice or rats following oral administration of MPM. In animals dosed with MPM by subcutaneous route, such inflammatory reactions as swelling, subcutaneous hyperemia and hemorrhage, and loss of hair incrustation at the site of injection were noted. Animals among those given MPM by intravenous injection developed postdosing depression of motor activity, respiratory depression or arrest, tremor and convulsion. 3. Deaths from administration of MPM were estimated to be due to paralysis of respiratory function inasmuch as fatally affected animals exhibited respiratory depression and cyanosis and, subsequently, respiratory arrest was followed by cardiac arrest. 4. Trace ingredients, metabolites and degradation products of MPM proved to be essentially the same as MPM in acute toxicities.
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PMID:[Acute toxicity studies of miporamicin and its degradation products and metabolites in the mouse and rat]. 262 83


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