Intrauterine growth restriction (IUGR) is associated with a reduction in the numbers of nephrons in neonates, which increases the risk of hypertension. Our previous study showed that ouabain protects the development of the embryonic kidney during IUGR. To explore this molecular mechanism, IUGR rats were induced by protein and calorie restriction throughout pregnancy, and ouabain was delivered using a mini osmotic pump. RNA sequencing technology was used to identify the differentially expressed genes (DEGs) of the embryonic kidneys. DEGs were submitted to the Database for Annotation and Visualization and Integrated Discovery, and gene ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were conducted. Maternal malnutrition significantly reduced fetal weight, but ouabain treatment had no significant effect on body weight. A total of 322 (177 upregulated and 145 downregulated) DEGs were detected between control and the IUGR group. Meanwhile, 318 DEGs were found to be differentially expressed (180 increased and 138 decreased) between the IUGR group and the ouabain-treated group. KEGG pathway analysis indicated that maternal undernutrition mainly disrupts the complement and coagulation cascades and the calcium signaling pathway, which could be protected by ouabain treatment. Taken together, these two biological pathways may play an important role in nephrogenesis, indicating potential novel therapeutic targets against the unfavorable effects of IUGR.

Retinal and visual function returns following retinal destruction by ouabain in adult goldfish (Carassius auratus). Although the precise cellular mechanisms are unclear, the ability to regenerate CNS neurons and connections that subsequently sustain visual behavior is remarkable, especially for an adult vertebrate. In this paper, we ask whether visual stimulation via new retinal cells can activate existing cells in the optic tectum, which normally receives the largest retinal projection in this species. The right eyes of adult goldfish were injected with ouabain. After 1–18 weeks the conscious, freely moving fish were exposed to spatially and temporally varying visual stimuli and the resulting tectal metabolic activity was determined with the autoradiographic deoxyglucose method. In normal controls without lesions, visual stimulation produced equally strong metabolic activity in both tectal hemispheres, peaking in the layer where most retinotectal projections terminate (N = 6). One week after ouabain injection, metabolic activity in the contralateral, deprived tectum was dramatically reduced (N = 5), closely resembling the effect of unilateral ocular enucleation (N = 5). However, 9–18 weeks after ouabain injection, metabolic activity in the deprived tectum recovered to a level that was statistically indistinguishable from normal controls (N = 6). These findings suggest that, after a comprehensive cytotoxic lesion of the retina, regenerated ganglion cells not only establish new connections with the preexisting optic tectum, but also effectively transmit visual information they receive from newly generated photoreceptors to the “old” tectum.