Gray C, Hukkanen M, Konttinen Y T, Terenghi G, Arnett T R, Jones S J, Burnstock G, Polak J M
Department of Anatomy and Developmental Biology, University College, London, U.K.
Neuroscience. 1992 Oct;50(4):953-63. doi: 10.1016/0306-4522(92)90218-q.
Deer antler is a unique mineralized tissue which can produce very high growth rates of > 1 cm/day in large species. On completion of antler growth, the dermal tissues which cover the antler are shed and the underlying calcified tissue dies. After several months the old antler is discarded and growth of a new one begins. It is known that deer antlers are sensitive to touch and are innervated. The major aims of this study were to identify and localize by immunohistochemical techniques the type of innervation present, and to find out whether nerve fibres could exhibit growth rates comparable to those of antler. We have taken tissue sections from the tip and shaft of growing Red deer (Cervus elaphus) antlers at three stages of development; shortly after the initiation of regrowth, the rapid growth phase, and near the end of growth. Incubation of tissue sections with antisera to protein gene product 9.5 (a neural cytoplasmic protein), neurofilament triplet proteins (a neural cytoskeletal protein), substance P and calcitonin gene-related peptide (both of which are present in and synthesized by sensory neurons) showed the presence of immunoreactive nerve fibres in dermal, deep connective and perichondrial/periosteal tissues at all stages of antler growth. The sparse distribution of vasoactive intestinal polypeptide-like immunoreactivity was found in dermal tissue only at the earliest stage of antler development. Nerve fibres immunoreactive to neuropeptide Y, C-flanking peptide of neuropeptide Y and tyrosine hydroxylase, all present in postganglionic sympathetic nerves, were not observed at any stage of antler growth. Nerves expressing immunoreactivity for any of the neural markers or peptides employed could not be found in cartilage, osteoid or bone. These results show that antlers are innervated mainly by sensory nerves and that nerves can attain the exceptionally high growth rates found in regenerating antler.
鹿茸是一种独特的矿化组织，在大型物种中其生长速度非常快，每天超过1厘米。鹿茸生长完成后，覆盖鹿茸的真皮组织会脱落，其下的钙化组织会死亡。几个月后，旧的鹿茸会脱落，新鹿茸的生长开始。已知鹿茸对触摸敏感且有神经支配。本研究的主要目的是通过免疫组织化学技术鉴定和定位现存的神经支配类型，并探究神经纤维的生长速度是否能与鹿茸相媲美。我们在三个发育阶段从生长中的马鹿（Cervus elaphus）鹿茸的尖端和主干取了组织切片；再生开始后不久、快速生长阶段以及生长接近尾声时。用针对蛋白基因产物9.5（一种神经细胞质蛋白）、神经丝三联体蛋白（一种神经细胞骨架蛋白）、P物质和降钙素基因相关肽（这两种物质都存在于感觉神经元中并由其合成）的抗血清孵育组织切片，结果显示在鹿茸生长的所有阶段，真皮、深层结缔组织以及软骨膜/骨膜组织中均存在免疫反应性神经纤维。仅在鹿茸发育的最早阶段，在真皮组织中发现了血管活性肠肽样免疫反应性的稀疏分布。在鹿茸生长的任何阶段均未观察到对神经肽Y、神经肽Y的C末端肽和酪氨酸羟化酶呈免疫反应性的神经纤维，这些物质均存在于节后交感神经中。在软骨、类骨质或骨中未发现对所使用的任何神经标记物或肽呈免疫反应性的神经。这些结果表明，鹿茸主要由感觉神经支配，并且神经能够达到再生鹿茸中发现的极高生长速度。
