A: Adrenaline from the nervous system lands on receptors of cardiac myocytes (heart-muscle cells), and this causes calcium channels in the membranes of those cells to open.
答：来自神经系统的肾上腺激素“着陆”到心脏肌细胞的受体，这使得这些肌细胞的膜中的钙通道打开。
2
Under normal conditions, the activity of the NMDA receptors is tightly regulated to prevent nerve cells from becoming overloaded with calcium.
正常情况下，NMDA受体活性较低从而保证神经细胞不会出现钙超载。
3
The results suggest that insulin could induce calcium ions release from secretory granules through the activation of IP3 receptors on granules.