Tasker A, Strain S M
Department of Anatomy and Physiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Canada.
Neuroreport. 1992 Sep;3(9):789-92. doi: 10.1097/00001756-199209000-00017.
The effect of systemic injections of morphine on behavioural toxicity and hippocampal (CA3 region) damage produced by both domoic and kainic acids was investigated in mice. Low doses of morphine (2.0 and 4.0 mg kg-1), but not higher doses, significantly antagonized the toxic response to a previously determined TD50 of domoic acid. By contrast, low doses of morphine had either minimal or no effect on the response to an equitoxic dose of kainic acid (TD50), but higher doses (6.0 and 8.0 mg kg-1) resulted in significant potentiation of kainate toxicity. These results provide the first evidence of a pharmacological dissociation between the mechanisms of domoic acid and kainic acid toxicity in vivo, suggesting that these two toxins produce behavioural and hippocampal toxicity via overlapping but non-identical mechanisms.
研究了在小鼠体内全身注射吗啡对由软骨藻酸和红藻氨酸所产生的行为毒性及海马体（CA3区）损伤的影响。低剂量吗啡（2.0和4.0毫克/千克）而非高剂量吗啡，可显著拮抗对先前确定的软骨藻酸半数中毒剂量（TD50）的毒性反应。相比之下，低剂量吗啡对同等毒性剂量红藻氨酸（TD50）的反应影响极小或无影响，但高剂量（6.0和8.0毫克/千克）则会导致红藻氨酸毒性显著增强。这些结果首次提供了体内软骨藻酸和红藻氨酸毒性机制之间药理学解离的证据，表明这两种毒素通过重叠但不完全相同的机制产生行为和海马体毒性。
