Serotonin depletion and barrel cortex development: Impact of growth impairment vs. serotonin effects on thalamocortical endings
Serotonin depletion and barrel cortex development: Impact of growth impairment vs. serotonin effects on thalamocortical endings
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DOI：
10.1093/cercor/10.2.181
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发表时间：
2000-02-01
期刊：
影响因子：
3.7
通讯作者：
Keller, F
中科院分区：
文献类型：
--
作者：
Persico, AM;Altamura, C;Keller, F
越来越多的证据支持血清素（5-羟色胺; 5-HT）在桶皮质发育中的作用。全身给予5-HT耗竭药物可降低新生大鼠躯体感觉皮层（SSC）的横截面须桶面积。在这里，我们通过比较5-HT消耗药物与减少蛋白质摄入药物的作用，评估了（i）5-HT消耗和（ii）脑生长下降（通常与药理学5-HT消耗有关）对桶形图案形成的相对影响。在出生后第6天（P6），在同一只动物中，在PO注射对氯苯丙胺（PCA）或对氯苯丙氨酸（PCPA）后，评估左半球SSC和右半球须桶区域中的5-HT水平。这两种药物显着降低皮质5-HT含量和平均桶面积在P6，但身体和大脑的增长。脑重量的差异占桶大小方差的84.4%，皮质5-HT含量的贡献可以忽略不计。在P14处死的PCPA给药动物产生了相似的趋势，尽管不太明显。最后，减少蛋白质摄入导致P6时体重和皮质5-HT水平降低，但脑重量或平均桶面积没有变化。因此，桶的形成似乎显着不太敏感的5-HT消耗本身比药物诱导的生长障碍。
Converging evidence supports a role of serotonin (5-hydroxytryptamine; 5-HT) in barrel cortex development. Systemic administration of 5-HT-depleting drugs reduces cross-sectional whisker barrel areas in the somatosensory cortex (SSC) of neonatal rats. Here we assess the relative impact on barrel pattern formation of (i) 5-HT depletion and (ii) decreased brain growth, which is often associated with pharmacological 5-HT depletion, by comparing the effects of 5-HT-depleting drugs with those of reduced protein intake. Left hemisphere 5-HT levels in the SSC and right hemisphere whisker barrel areas were assessed at postnatal day 6 (P6) in the same animal following injection of p-chloroamphetamine (PCA) or p-chlorophenylalanine (PCPA) at PO. Both drugs significantly reduced cortical 5-HT content and mean barrel areas at P6, but also body and brain growth. Differences in brain weight accounted for 84.4 % of the variance in barrel size, with negligible contributions by cortical 5-HT content. PCPA-treated animals sacrificed at P14 yielded similar trends, albeit less pronounced. Finally, reduced protein intake resulted in lower body weight and cortical 5-HT levels at P6, but yielded no change in brain weight or mean barrel area. Barrel formation therefore appears markedly less sensitive to 5-HT depletion per se than to drug-induced growth impairment.