Intercalated cells of the amygdala mPFC) in both primates and rodents, which may explain cortical control over emotional regulation processes such as extinction. Intercalated cells of the amygdala The intercalated (ITC) cells of the amygdala are a group of GABAergic neurons situated between the basolateral and central nuclei of the amygdala that are important for inhibitory control over the amygdala. ITC cells are thought to play a role as the 'off switch' for the amygdala, inhibiting the amygdala's central nucleus output neurons and its basolateral nucleus neurons. Some researchers speculate that ITC cells, via their extensive local inhibition within the amygdala, could serve as a
Systole Systole of the heart is initiated by electrically excitable cells situated in the sinoatrial node. These cells are activated spontaneously by depolarization of the electrical potential across their cell membranes, which causes voltage-gated calcium channels on the cell membrane to open and allow calcium ions to pass through into the sarcoplasm (cytoplasm) of cardiac muscle cells. Calcium ions bind to molecular receptors on the sarcoplasmic reticulum (see graphic), which causes a flux (flow) of calcium ions into the sarcoplasm. Calcium ions bind to troponin C, causing a conformational (i.e., structural) change in the troponin-tropomyosin protein complex, causing the myosin head