Since the nucleus tractus solitarii (NTS) is a pivotal region for regulating the set-point of arterial pressure, we proposed a role for it in the development of neurogenic hypertension. Our previous findings suggest that the NTS of pre-hypertensive and hypertensive rats (SHR) exhibits abnormal inflammatory condition with elevated anti-apoptotic factors, compared to the normotensive rats WKY (1,2). Whether this chronic condition affects the neuronal growth and plasticity in the NTS remains unknown. To unveil the characteristics of the neurodevelopmental environment in the NTS of SHR, we investigated the expression of neurotrophin transcripts and proteins in SHR. Male animals were humanely killed by cervical dislocation and the NTS was dissected out. To screen for differentially expressed neurotrophin transcripts between the NTS of adult SHR and WKY, total RNAs were extracted from the NTS (SHR & WKY, 10 weeks old, n=6) and submitted to the RT2 Profiler PCR Array system targeting rat neurotrophins and their receptors. Genes showing more than 1.5 fold differences in their expression levels between two groups were targeted for further validation using quantitative real-time RT-PCR (SHR & WKY, 3 & 10 weeks old, n=6 each). Their protein expression levels were also assessed in NTS protein extracts from adult animals (SHR & WKY, 10 weeks old, n=12) by using semi-quantitative western-blotting. The data (means ± S.E.M.) were shown as relative fold differences in SHR compared to WKY and unpaired t-test was used. Gene expression of Gfrα3 (Glial cell line-derived neurotrophic factor family receptor alpha-3), which is known to be involved in neuronal survival and migration, was up-regulated (SHR vs WKY: 2.48±0.31 vs 1.08±0.23 p<0.01) in the NTS of adult SHR, while gene expression of Crhbp (Corticotropin releasing hormone binding protein), a potential neurogenesis modulator, was down-regulated (0.131±0.03 vs 1.15±0.27 p<0.001). In parallel, Gfrα3 protein expression was up-regulated (1.36±0.08 vs 1.00±0.08 p<0.01), whereas Crhbp protein expression was down-regulated (0.79±0.04 vs 1.00±0.08 p<0.05) in the NTS of adult SHR. In pre-hypertensive young animals, the Gfrα3 transcript was found increased (1.37±0.08 vs 1.05±0.12 p<0.05) in the NTS of SHR, while Crhbp transcript did not show any differential expression. Together with our previous results showing that the transcript level of Tnfrsf6 (Tumor necrosis factor receptor superfamily, member 6, Fas), known to be involved in neuronal death and branching, was down-regulated in the NTS of both pre-hypertensive and hypertensive SHR (2), these profiles may affect the development of neuronal circuitry regulating cardiovascular autonomic activity and hence result in the development of neurogenic hypertension in the SHR.