運動終板(motor end plate)是指哪一處的構造？
運動終板(motor end plate)是指哪一處的構造？
依據以下各生理學教科書的定義，運動神經與肌纖維交接處稱為「神經肌肉會合處(neuromuscular
junction)」，此結構相當於突觸，而「運動終板(motor
end plate) 」是指神經肌肉會合處中面對運動神經軸突末梢的肌細胞細胞膜區域，相當於是突觸後的細胞膜區域。
l
甘龍生理學(Barrett, et al., 2010)：the motor end plate, the
thickened portion of the muscle membrane at the junction
l
人體生理學(Sherwood, 2016)：The entire axon terminal ending (all the fine
branches with terminal buttons) fits into a shallow depression, or groove, in
the underlying muscle fiber. This specialized underlying portion of the muscle
cell membrane is called the motor end
plate (❙ Figure
7-5).
l
醫學生理學(Boron and Boulpaep, 2017)：a motor nerve axon contacts each muscle fiber near
the middle of the fiber to form a synapse called the neuromuscular junction. The specialized region of sarcolemma in
closest contact with the presynaptic nerve terminal is called the motor end plate.
l
解剖與生理學(Tortora
and Derrickson, 2009)：Muscle
action potentials arise at the neuromuscular
junction (NMJ), the synapse between a somatic motor neuron and a skeletal
muscle fiber (Figure 10.10a)…..The region of the sarcolemma opposite the
synaptic end bulbs, called the motor end
plate (Figure 10.10b, c), is the muscle fiber part of the NMJ.
運動終板上含有乙醯膽鹼受體，在受乙醯膽鹼刺激後會引發Na+與K+的跨膜流動，進而引發去極化，此處的電位變化稱為「終板電位(end-plate
potentials)」，屬於肌細胞的局部電位，相當於是突觸結構中的突觸後電位(postsynaptic
potential, PSP)，也稱為樹突電位(dendritic
potential)，是神經-肌肉生力互動的重要指標。
就如同突觸後電位(樹突電位)不可直接稱為突觸電位，終板電位亦不可稱為神經肌肉會合處電位，神經肌肉會合處與運動終板在神經生理學領域中實屬不同的意思，為了幫助學生未來可順利銜接大學課程，建議在高中階段就將神經肌肉會合處與運動終板兩個名詞的定義釐清，以避免未來部分學生投入神經生理學領域時會錯亂。
參考資料：
Barrett, K. E.,
Barman, S. M., Boitano, S. and Brooks, H. L. 2010. Ganong's Review of Medical
Physiology(23th Edition). McGraw-Hill.
Sherwood, L.
2016. Human Physiology From Cells to System 9th ED. Cengage Learning.
Boron, W. F. and
Boulpaep, E. L. 2017. Medical Physiology 3rd ED. Elsevier.
Tortora,
G. J. and Derrickson, B. H. 2009. Principles of anatomy and Physiology 12th ED.
John Wiley & Sons.
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