Durham D, Rubel E W
J Comp Neurol. 1985 Jan 22;231(4):446-56. doi: 10.1002/cne.902310404.
We have examined one of the metabolic consequences of unilateral cochlea (basilar papilla) removal in the chick brain stem auditory system. We assessed changes in succinate dehydrogenase (SDH), a mitochondrial enzyme involved in energy metabolism, in neurons of second-order n. magnocellularis (NM) and third-order n. laminaris (NL). Chickens undergoing surgery at 10 days of age were perfused 4 hours to 35 days postlesion. Chickens 6 or 66 weeks of age at cochlea removal were examined 1 or 8 days after surgery. In all groups, cryostat sections were prepared for SDH histochemistry or Nissl staining. In normal chickens, NM cell bodies and NL neuropil contain SDH reaction product. In young birds, the density of SDH reaction product in NM shows a rapid biphasic response to cochlea removal. From 8 to 60 hours postlesion, density increases ipsilateral to cochlea removal; for survival times of 3-35 days, SDH density decreases in ipsilateral NM. In NL, no changes were observed until 3 days after cochlea removal. Then we observed a long-lasting decrease in density of SDH reaction product in the neuropil regions receiving input from the deafferented NM. All of these changes are age-dependent in that they were observed only following cochlea removal on or before 6 weeks of age.
我们研究了雏鸡脑干听觉系统单侧耳蜗（基底乳头）切除后的一种代谢后果。我们评估了参与能量代谢的线粒体酶琥珀酸脱氢酶（SDH）在二级大细胞神经核（NM）和三级层状神经核（NL）神经元中的变化。10日龄接受手术的雏鸡在损伤后4小时至35天进行灌注固定。6周龄或66周龄时切除耳蜗的雏鸡在手术后1天或8天进行检查。在所有组中，制备低温恒温器切片用于SDH组织化学或尼氏染色。在正常雏鸡中，NM细胞体和NL神经纤维网含有SDH反应产物。在幼鸟中，NM中SDH反应产物的密度对耳蜗切除呈现快速双相反应。损伤后8至60小时，切除耳蜗同侧的密度增加；存活3至35天时，同侧NM中的SDH密度降低。在NL中，直到耳蜗切除后3天才观察到变化。然后我们观察到，在接受去传入NM输入的神经纤维网区域，SDH反应产物的密度出现长期降低。所有这些变化都与年龄有关，因为它们仅在6周龄及以前切除耳蜗后才观察到。
