Li Y, Hsieh S T, Chien H F, Zhang X, McArthur J C, Griffin J W
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.
Exp Neurol. 1997 Oct;147(2):452-62. doi: 10.1006/exnr.1997.6624.
Denervation in man often results in shiny, dry, thin skin. A previous study has shown that the epidermis of glabrous skin in the rat becomes approximately 40% thinner within 1 week following sciatic nerve transection, but which nerve fiber type or types influence epidermal thickness is unknown. In this study, we compared the effects on the epidermis of selective sensory, motor, and sympathetic denervation. Protein gene product 9.5 and calcitonin gene-related peptide immunocytochemical staining were used to determine the extent of denervation of epidermis, dermis, and sweat glands in the footpads. Epidermal thickness of the glabrous plantar skin of the foot was measured. To verify the specificity and reliability of each animal model, the relevant regions of the peripheral nervous system were examined by light or electron microscopy or both. Epidermal thickness decreased significantly following sciatic nerve transection (58% of control, P < 0.05) and dorsal root ganglionectomy (59%; P < 0.05). The thickness also decreased following lumbar ventral rhizotomy (61%; P < 0.01), destruction of lumbar spinal motor neurons (66%; P < 0.05), and botulinum toxin-induced paralysis of the tibialis anterior and gastrocnemius muscles (70%; P < 0.05). A slight decrease followed dorsal rhizotomy (84%; P < 0.01). In contrast, no significant alterations in epidermal thickness were detected following sham operation and sympathectomy. Epidermal thinning was paralleled by reductions in the amounts of transcripts for glyceraldehyde-3-phosphate dehydrogenase and beta-actin. These results suggest that selective loss of both sensory and motor fibers to the hind limb can contribute to reducing epidermal thickness in rat foot glabrous skin.
人类的去神经支配通常会导致皮肤发亮、干燥且变薄。先前的一项研究表明，大鼠无毛皮肤的表皮在坐骨神经横断后1周内变薄约40%，但尚不清楚是哪种或哪些神经纤维类型影响表皮厚度。在本研究中，我们比较了选择性感觉、运动和交感神经去神经支配对表皮的影响。采用蛋白基因产物9.5和降钙素基因相关肽免疫细胞化学染色来确定脚垫表皮、真皮和汗腺的去神经支配程度。测量足部无毛足底皮肤的表皮厚度。为了验证每个动物模型的特异性和可靠性，通过光学显微镜或电子显微镜或两者对周围神经系统的相关区域进行检查。坐骨神经横断（为对照组的58%，P<0.05）和背根神经节切除术（59%；P<0.05）后表皮厚度显著降低。腰腹侧神经根切断术（61%；P<0.01）、腰脊髓运动神经元破坏（66%；P<0.05）以及肉毒杆菌毒素诱导的胫前肌和腓肠肌麻痹（70%；P<0.05）后表皮厚度也降低。背根切断术后有轻微降低（84%；P<0.01）。相比之下，假手术和交感神经切除术后未检测到表皮厚度有显著变化。表皮变薄与甘油醛-3-磷酸脱氢酶和β-肌动蛋白转录本数量的减少平行。这些结果表明，后肢感觉和运动纤维的选择性丧失可导致大鼠足部无毛皮肤的表皮厚度降低。
