Acute Putrescine Supplementation with Schwann Cell Implantation Improves Sensory and Serotonergic Axon Growth and Functional Recovery in Spinal Cord Injured Rats

Figure 4

Putrescine supplementation enhances serotonergic axon numbers within the SC implant. Immunochemical staining for serotonergic axons (green, representative examples indicated by white arrows) shows many more axons within the rostral part of the SC implant (identified by p75 labeling, red) following (b) acute putrescine delivery compared to (a) when vehicle is given. Scale bar = 20 μm. Dotted white lines indicate the extent of the SC implant. (c) Stereological analysis shows a significant increase in 5HT⁺ axon numbers with putrescine; the greatest effects are seen further from the center of the SC implant (i.e., closer to rostral host cord SC implant interface) and with acute administration. Statistical significance indicated at , , and compared to the vehicle control group and and compared to acute putrescine treatment.

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