Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The ability of a supralethal dose of chlorpyrifos to produce delayed neuropathy was examined using assessments of clinical signs, electromyography (EMG), motor nerve conduction velocity (MNCV), lymphocyte neuropathy target esterase activity (LNTE), and histologic changes in nervous system tissues. Cats were exposed to a single, im injection of corn oil (vehicle control), DFP (positive control) at 5.0 mg/kg, or chlorpyrifos at 300 mg/kg and observed for 60 days. Atropine and 2-PAM were administered to chlorpyrifos exposed cats one to two times a day for 14 to 24 days in response to the appearance of cholinergic signs. Anorectic cats during the acute toxicosis were force fed by hand and hydration was maintained by administering fluids sc. Onset of ataxia (mean +/- SD) for the positive control and chlorpyrifos exposed cats were 16.2 +/- 1.8 days (range of 14-19 days) and 19.0 +/- 1.4 days (range of 17-21 days), respectively. Functional deficits for both groups were confined to the hindlimbs and characterized by a crouched-waddling gait, hypermetria, and proprioceptive deficits. Maximal inhibition of LNTE activity was 96% at 24 hr postdosing in the positive control group and 46% at 7 days postdosing in the chlorpyrifos group. No EMG or MNCV abnormalities were detected in any of the treatment groups. Axonal degeneration was similar for the positive control and chlorpyrifos exposed cats. Ascending tracts of the cervical spinal cord and descending tracts of the thoracic and lumbar spinal cord were most severely affected and peripheral nerves were only mildly affected. The clinical and histologic effects produced indicate that chlorpyrifos can cause delayed neuropathy in the domestic cat. The moderate but prolonged inhibition of LNTE produced by chlorpyrifos is atypical of classic organophosphorus delayed neurotoxicants.
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PMID:Clinical, biochemical, electrophysiologic, and histologic assessment of chlorpyrifos induced delayed neuropathy in the cat. 128 30

Nicotine (0.5 and 1.0 mg/kg) administered subcutaneously to mice decreased the ambulatory activity recorded by an ambulo-meter in a dose-dependent manner from 5 to 60 min after the administration, and the higher dose (1.0 mg/kg) caused a long-lasting ataxia. To be noted was the initial increment of ambulation which usually preceded the ataxia-inducing effect with every dose of nicotine, and the lowest dose (0.10 mg/kg) employed herein induced only the increasing effect on ambulation recorded for the first 20 min after its administration. The ataxia-inducing effect of nicotine (1.0 mg/kg) was attenuated by the pretreatment with mecamylamine (0.4-2.0 mg/kg) in a dose-dependent manner, though the attenuating effect waned at a higher dose (4.0 mg/kg). In contrast, pretreatment with either hexamethonium (2.5 and 5.0 mg/kg) or atropine (1.0, 2.5 and 5.0 mg/kg) did not affect the ataxia-inducing effect of nicotine. Atropine when administered alone was found to markedly increase the ambulatory activity at the doses used for the pretreatment. Measurement of the time-dependent change of [3H]-nicotine level in brain tissue after its subcutaneous injection revealed that there is a good correlation between the brain levels of the alkaloid and the intensity of its ataxic effect rather than the initial increasing effect on ambulation. The results obtained herein suggest that nicotine exerts its ataxic effect centrally, but the site and type of the receptor stimulated by nicotine remains to be identified.
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PMID:Effects of nicotine on ambulatory activity in mice. 337 24

The effect on behavior of eight anticholinergic agents: atropine, scopolamine, trihexyphenidyl, biperiden, homatropine, eucatropine, hexocyclium and propantheline, injected into the cerebral ventricle (ICV) of the cat was investigated and compared. The anticholinergic agents evoked: (1) psychomotor stimulation such as miaowing, loud calling, restlessness, impelling locomotion, jumping, vacant staring, apprehension and loss of interest of the surroundings; (2) aggression, hissing, threat, attack, defense, fighting with paws and flight; (3) autonomic responses including mydriasis, tachypnea, dyspnea, licking, vomiting, salivation, micturition and defection; and (4) motor phenomena comprising scratching, ataxia, rigidity, tremor, weakness with adynamia or myoclonic jerks. Convulsions appeared only after ICV injections of atropine and homatropine. The most characteristic behavioral effect of anticholinergic agents was psychomotor stimulation accompanied by mild aggressive responses. The only exception was propantheline which caused a muscular weakness and adynamia. Atropine and scopolamine alone induced a dose-dependent impelling locomotion as well as fighting behavior. Carbachol and eserine injected intracerebroventricularly reversed the locomotion autonomic and motor phenomena produced by anticholinergic agents administered similarly. It is suggested that anticholinergic agents acting as partial agonists, can produce their behavioral effects through central cholinoceptive sites.
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PMID:Comparative behavioral effects of anticholinergic agents in cats: psychomotor stimulation and aggression. 370 93