Abstract |
Adult rats treated IP with domoic acid at 0, 0.22, 0.65, or 1.32 mg/kg were tested for passive avoidance (PA), auditory startle (AS), or conditioned avoidance (CAR) behaviors. Clinical signs were observed only at the 1.32 mg/kg dose level. Within 24 h of dosing, rats surviving a dose of 1.32 mg/kg exhibited transient decreased body weight and exaggerated AS responding. Startle latency and habituation, PA, and CAR were not affected. Examination of brains from six rats per group revealed a subset (2/6) of animals receiving 1.32 mg/kg domoic acid with degenerating neurons in the hippocampal CA1/CA3 subregions and gliosis. The decreased body weight and increased startle suggest a hyperreactivity syndrome possibly related to neuronal degeneration in the hippocampus. In a separate experiment, domoic acid at an IP dose of 0.93 mg/kg was found to produce hypomotility in addition to a decrease in body weight. Both effects were reduced by pretreatment with scopolamine (2 mg/kg), but not with caffeine (30 mg/kg), indicating a possible cholinergic involvement in domoate's toxicity.
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Authors | T J Sobotka, R Brown, D Y Quander, R Jackson, M Smith, S A Long, C N Barton, R L Rountree, S Hall, P Eilers, J N Johannessen, A C Scallet |
Journal | Neurotoxicology and teratology
(Neurotoxicol Teratol)
1996 Nov-Dec
Vol. 18
Issue 6
Pg. 659-70
ISSN: 0892-0362 [Print] United States |
PMID | 8947943
(Publication Type: Journal Article)
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Chemical References |
- Neurotoxins
- domoic acid
- Kainic Acid
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Topics |
- Acoustic Stimulation
- Analysis of Variance
- Animals
- Astrocytes
(drug effects, pathology)
- Avoidance Learning
(drug effects)
- Body Weight
- Conditioning, Operant
- Dose-Response Relationship, Drug
- Habituation, Psychophysiologic
- Hippocampus
(drug effects, pathology)
- Injections, Intraperitoneal
- Kainic Acid
(analogs & derivatives, toxicity)
- Male
- Neurotoxins
(toxicity)
- Rats
- Rats, Sprague-Dawley
- Reflex, Startle
(drug effects)
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