Milot J, Côté C H, Tremblay R R
Laboratoire de Biorégulation Hormonale, Centre Hospitalier, de l'Université Laval, Québec, Canada.
Muscle Nerve. 1994 Dec;17(12):1431-8. doi: 10.1002/mus.880171212.
Carbonic anhydrase III (CA III), the predominant CA isoform in skeletal muscle is very sensitive to neuronal influences. We aimed to determine whether CA III expression could be influenced by neurotrophic factor(s) present in sciatic nerve extract (SNE). Intact muscles were thus compared with denervated soleus (SOL), extensor digitorum longus (EDL), and tibialis anterior (TA) muscles injected daily for 7 days with saline solution (SS) or with SNE. CA III activity was significantly increased in SS-treated EDL and TA muscles compared to control (CTR), while SNE injections partially prevented this increase. There was no significant difference for CA III activity in the SOL between CTR, SS, and SNE groups. The CA III mRNA increase observed in response to denervation was reduced by 40% in SNE-treated EDL and TA muscles. While SOL CA III mRNA level was not affected by denervation, a 52% decrease was observed with SNE. We concluded that neuronal modulation of CA III expression in type II fibers may involve a neurotrophic component.
碳酸酐酶III（CA III）是骨骼肌中主要的CA同工型，对神经元影响非常敏感。我们旨在确定CA III的表达是否会受到坐骨神经提取物（SNE）中神经营养因子的影响。因此，将完整肌肉与去神经支配的比目鱼肌（SOL）、趾长伸肌（EDL）和胫骨前肌（TA）进行比较，这些肌肉每天注射生理盐水（SS）或SNE，持续7天。与对照组（CTR）相比，SS处理的EDL和TA肌肉中CA III活性显著增加，而注射SNE可部分阻止这种增加。CTR、SS和SNE组之间SOL中CA III活性无显著差异。在SNE处理的EDL和TA肌肉中，因去神经支配而观察到的CA III mRNA增加减少了40%。虽然SOL的CA III mRNA水平不受去神经支配的影响，但在SNE处理下观察到其下降了52%。我们得出结论，II型纤维中CA III表达的神经元调节可能涉及神经营养成分。
