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

<div>Putrescine administration increases peptidergic axon numbers within the SC implant. Immunochemical staining for peptidergic axons with CGRP (green, representative examples indicated by white arrows) shows that many more axons are present within SC implants (p75 labeling, red) following (b) acute putrescine delivery compared to (a) when vehicle is given. Scale bar = 20 <i>μ</i>m. Dotted white lines indicate the extent of the SC implant. (c) Stereological analysis revealed a significant increase in CGR<svg height="10.8465pt" id="M65" style="vertical-align:-0.04980087pt" version="1.1" viewbox="-0.0498162 -10.7967 13.5251 10.8465" width="13.5251pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M46 650V622C120 617 128 613 128 525V125C128 42 120 34 40 28V0H311V28C221 34 212 39 212 124V281L286 262C297 261 316 261 331 263C429 275 526 338 526 468C526 533 501 579 462 609C422 638 364 650 293 650H46ZM212 559C212 588 215 600 223 606C230 613 251 618 279 618C361 618 430 572 430 464C430 337 350 302 285 302C252 302 225 309 212 314V559Z" id="g121-78"></path><glyph.data ascent="989" descent="-360" horiz-adv-x="563" vert-adv-y="563"></glyph.data></g><g transform="matrix(.0091,0,0,-0.0091,7.319,-5.741)"><path d="M556 236V289H337V504H275V289H56V236H275V-4H337V236H556Z" id="g54-36"></path><glyph.data ascent="3443" descent="-2856" horiz-adv-x="611" vert-adv-y="611"></glyph.data></g></svg> axon numbers with putrescine: the greatest effects are observed within the SC implants with acute putrescine administration. Statistical significance indicated at <svg height="13.9365pt" id="M66" style="vertical-align:-3.834pt" version="1.1" viewbox="-0.0498162 -10.1025 68.0304 13.9365" width="68.0304pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M486 158C486 177 478 202 466 220C413 228 386 236 336 262C386 288 413 297 466 304C478 323 486 347 485 366C470 376 444 381 422 380C389 338 368 319 321 288C323 345 329 372 349 422C339 442 322 461 305 470C289 461 271 442 262 422C281 372 287 345 290 288C243 319 222 338 189 380C167 381 142 376 125 366C125 347 133 322 145 304C198 296 225 288 275 262C225 236 198 227 145 220C133 201 125 177 126 158C141 148 167 143 189 144C222 186 243 205 290 236C288 179 282 152 262 102C272 82 289 63 306 54C322 63 340 82 350 102C330 152 324 179 321 236C368 205 390 186 422 144C444 143 470 148 486 158Z" id="g50-43"></path><glyph.data ascent="3443" descent="-2856" horiz-adv-x="611" 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ascent="3473" descent="-2876" horiz-adv-x="480" vert-adv-y="480"></glyph.data></g></svg> compared to acute putrescine treatment.</div>

Neural Plasticity

fig5

Figure 5

Figure 5: Acute Putrescine Supplementation with Schwann Cell Implantation Improves Sensory and Serotonergic Axon Growth and Functional Recovery in Spinal Cord Injured Rats 

Figure 5 | Acute Putrescine Supplementation with Schwann Cell Implantation Improves Sensory and Serotonergic Axon Growth and Functional Recovery in Spinal Cord Injured Rats 