Ferchmin P A, Eterović V A
Department of Biochemistry, School of Medicine, Universidad Central del Caribe, Cayey, Puerto Rico 00634.
Pharmacol Biochem Behav. 1990 Jan;35(1):255-8. doi: 10.1016/0091-3057(90)90235-a.
The effect of brief periods of experience in an enriched environment (7 hours per day for 3 days), and of inhibition of polyamine synthesis was studied in four brain regions: occipital cortex, remaining cortex, subcortex and cerebellum plus medulla. Polyamine synthesis was inhibited by alpha-difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase. DFMO caused a 30-50% decrease in putrescine content in all brain areas, irrespective of the environmental treatment. Spermidine was decreased by the inhibitor in subcortex and in cerebellum plus medulla, while spermine was increased in remaining cortex. The regional differences in inhibitor effect suggest that the regulation of polyamine metabolism varies among the four brain areas. Experience increased the weight and spermidine content of remaining cortex and decreased putrescine content of occipital cortex. Noncortical areas were not affected. The effects of experience on polyamine levels were somewhat increased by DFMO. Therefore, experience did not have a generalized effect on polyamine levels; rather, each polyamine responded in a specific manner. In addition, polyamine levels were affected only in those brain areas which are known from previous studies to respond to environmental stimulation with weight increase. These facts suggest that polyamines might have a role in the regulation of experience-induced plasticity.
研究了在丰富环境中短暂经历（每天7小时，共3天）以及抑制多胺合成对四个脑区的影响，这四个脑区分别是枕叶皮质、其余皮质、皮质下区域以及小脑加延髓。多胺合成通过α-二氟甲基鸟氨酸（DFMO）来抑制，DFMO是鸟氨酸脱羧酶的不可逆抑制剂。无论环境处理如何，DFMO都会使所有脑区的腐胺含量降低30 - 50%。抑制剂使皮质下区域以及小脑加延髓中的亚精胺含量降低，而使其余皮质中的精胺含量增加。抑制剂作用的区域差异表明，四个脑区中多胺代谢的调节各不相同。经历增加了其余皮质的重量和亚精胺含量，并降低了枕叶皮质的腐胺含量。非皮质区域未受影响。DFMO在一定程度上增强了经历对多胺水平的影响。因此，经历对多胺水平没有普遍影响；相反，每种多胺的反应方式都有所不同。此外，多胺水平仅在先前研究中已知会因环境刺激而重量增加的那些脑区受到影响。这些事实表明，多胺可能在调节经验诱导的可塑性中发挥作用。
