Vertebrate striated muscle contraction is controlled (regulated) by the action of the proteins troponin and tropomyosin on the actin filaments. Nervous stimulation causes a depolarisation of the muscle membrane (sarcolemma) which triggers the release of calcium ions from the sarcoplasmic reticulum.
n. 1  Abnormally fast or deep respiration, which results in the loss of carbon dioxide from the blood, thereby causing a fall in blood pressure, tingling of the extremities, and sometimes fainting.
Slow Respiratory Rate. When a person's respiratory rate is slower than normal, certain conditions, such as bradypnea or apnea, may occur. Bradypnea is characterized by abnormally slow breathing, and may be the symptom of a metabolic disorder or a tumor.