Kazan Institute of Biochemistry and Biophysics FRC Kazan Scientific Center of RAS, Kazan, Russia.
Cell Mol Neurobiol. 2021 Mar;41(2):395-401. doi: 10.1007/s10571-020-00840-3. Epub 2020 Apr 9.
The long history of studies on the effect of catecholamines on synaptic transmission does not answer the main question about the mechanism of their action on quantal release in the neuromuscular junction. Currently, interest in catecholamines has increased not only because of their widespread use in the clinic for the treatment of cardiovascular and pulmonary diseases but also because of recent data on their possible use for the treatment of certain neurodegenerative diseases, muscle weakness and amyotrophic sclerosis. Nevertheless, the effects and mechanisms of catecholamines on acetylcholine release remain unclear. We investigated the action of noradrenaline and adrenaline on the spontaneous and evoked quantal secretion of acetylcholine in the neuromuscular junction of the rat soleus muscle. Noradrenaline (10 μM) did not change the spontaneous acetylcholine quantal release, the number of released quanta after nerve stimulation, or the timing of the quantal secretion. However, adrenaline at the same concentration increased spontaneous secretion by 40%, increased evoked acetylcholine quantal release by 62%, and synchronized secretion. These effects differ from those previously described by us in the synapses of the frog cutaneous pectoris muscle and mouse diaphragm. This indicates specificity in catecholamine action that depends on the functional type of muscle and the need to take the targeted type of muscle into account in clinical practice.
关于儿茶酚胺对神经肌肉接头量子释放作用机制的研究已有很长的历史，但仍未回答其作用的主要问题。儿茶酚胺目前不仅因其在心血管和肺部疾病治疗中的广泛应用而引起关注，还因其在某些神经退行性疾病、肌肉无力和肌萎缩性侧索硬化症的治疗中的潜在应用而受到关注。然而，儿茶酚胺对乙酰胆碱释放的作用和机制仍不清楚。我们研究了去甲肾上腺素和肾上腺素对大鼠比目鱼肌神经肌肉接头中乙酰胆碱自发和诱发量子分泌的作用。去甲肾上腺素（10 μM）并未改变自发乙酰胆碱量子释放、神经刺激后释放的量子数量或量子分泌的定时。然而，相同浓度的肾上腺素使自发分泌增加了 40%，诱发的乙酰胆碱量子释放增加了 62%，并使分泌同步化。这些作用与我们之前在青蛙皮胸肌和小鼠膈肌突触中描述的作用不同。这表明儿茶酚胺的作用具有特异性，取决于肌肉的功能类型，在临床实践中需要考虑靶向肌肉的类型。
