Brodfuehrer P D, Hoy R R
Section of Neurobiology and Behavior, Cornell University, Ithaca, New York 14853.
J Neurobiol. 1988 Jan;19(1):17-38. doi: 10.1002/neu.480190104.
In adult crickets, Teleogryllus oceanicus, unilateral auditory deafferentation causes the medial dendrites of an afferent-deprived, identified auditory interneuron (Int-1) in the prothoracic ganglion to sprout and form new functional connections in the contralateral auditory neuropil. The establishment of these new functional connections by the deafferented Int-1, however, does not appear to affect the physiological responses of Int-1's homolog on the intact side of the prothoracic ganglion which also innervates this auditory neuropil. Thus it appears that the sprouting dendrites of the deafferented Int-1 are not functionally competing with those of the intact Int-1 for synaptic connections in the remaining auditory neuropil following unilateral deafferentation in adult crickets. Moreover, we demonstrate that auditory function is restored to the afferent-deprived Int-1 within 4-6 days following deafferentation, when few branches of Int-1's medial dendrites can be seen to have sprouted. The strength of the physiological responses and extent of dendritic sprouting in the deafferented Int-1 progressively increase with time following deafferentation. By 28 days following deafferentation, most of the normal physiological responses of Int-1 to auditory stimuli have been restored in the deafferented Int-1, and the medial dendrites of the deafferented Int-1 have clearly sprouted and grown across into the contralateral auditory afferent field. The strength of the physiological responses of the deafferented Int-1 to auditory stimuli and extent of dendritic sprouting in the deafferented Int-1 are greater in crickets deafferented as juveniles than as adults. Thus, neuronal plasticity persists in Int-1 following sensory deprivation from the earliest juvenile stages through adulthood.
在成年海氏田蟋（Teleogryllus oceanicus）中，单侧听觉传入神经切断会导致前胸神经节中一个传入神经被剥夺的、已确定的听觉中间神经元（Int-1）的内侧树突萌发，并在对侧听觉神经纤维网中形成新的功能连接。然而，去传入神经的Int-1建立这些新的功能连接似乎并未影响前胸神经节完整侧Int-1同系物的生理反应，该同系物也支配这个听觉神经纤维网。因此，在成年蟋蟀单侧去传入神经后，去传入神经的Int-1萌发的树突似乎并未与完整的Int-1的树突在剩余的听觉神经纤维网中竞争突触连接。此外，我们证明，在去传入神经后的4 - 6天内，传入神经被剥夺的Int-1的听觉功能得以恢复，此时几乎看不到Int-1内侧树突的分支有萌发。去传入神经的Int-1的生理反应强度和树突萌发程度在去传入神经后随时间逐渐增加。去传入神经28天后，去传入神经的Int-1对听觉刺激的大多数正常生理反应已恢复，并且去传入神经的Int-1的内侧树突已明显萌发并生长到对侧听觉传入区域。幼年去传入神经的蟋蟀中，去传入神经的Int-1对听觉刺激的生理反应强度和树突萌发程度比成年去传入神经的蟋蟀更大。因此，从最早的幼年阶段到成年，感觉剥夺后Int-1中神经元可塑性持续存在。
