Hormonal Control of an Avian Neuromuscular System

对神经生物学家来说，一个重要的问题是成年中枢神经系统（CNS）的神经元是否能够再生或再生长成功能性神经组织。 这些能力对于修复CNS的努力至关重要。 对一些鸟类的研究表明，类固醇激素可以对大脑产生显着影响，包括在成年人的神经元重建（可塑性）中发挥作用。 虽然哺乳动物脊髓可塑性的证据有限，但对鸟类脊髓中类固醇的作用（包括对神经可塑性的影响）一无所知。 Schlinger博士已经确定了一种鸟类模型（巴拿马的金领侏儒鸟），似乎具有以脊髓为中心的类固醇敏感神经肌肉系统。 在初步研究中，他发现雄性侏儒鸟脊髓中的许多神经元积累雄激素，还发现了一种翅膀肌肉的大小是两性异形的。 这些观察结果表明，雄激素可能对这些鸟类的脊髓和肌肉组织都有作用。 Schlinger博士建议确定这些鸟类的神经和肌肉结构的类固醇敏感性和性二型性的全部程度，并评估雄激素是否影响它们的生长和功能。 这些研究将促进对类固醇控制复杂行为的理解，包括脊髓性分化和神经可塑性。

An important issue to neurobiologists is whether neurons of the adult central nervous system (CNS) are capable of regenerating or regrowing into functional nervous tissue. These capabilities are critical for efforts to repair the CNS. Studies of some birds have revealed that steroid hormones can have significant effects on the brain, including playing a role in neuronal restructuring (plasticity) in adults. While there is limited evidence for plasticity in the mammalian spinal cord, nothing is known about steroid actions, including effects on neural plasticity, in the avian spinal cord. Dr. Schlinger has identified an avian model (the Golden-collared manakin of Panama) that appears to have a steroid-sensitive neuromuscular system centered in the spinal cord. In pilot studies, he found that many neurons in the male manakin spinal cord accumulate androgens and also identified one wing muscle that is sexually dimorphic in size. These observations suggest that androgens may act on both the spinal cord and musculature of these birds. Dr. Schlinger proposes to determine the full extent of the steroid sensitivity and sexual dimorphism of neural and muscular structures of these birds and evaluate whether androgens influence their growth and function. These studies will advance the understanding about steroid control of complex behaviors, including spinal cord sexual differentiation and neural plasticity.