Angiotensin II is a potent vaso-active peptide that causes blood vessels to constrict, resulting in increased blood pressure. Angiotensin II also stimulates the secretion of the hormone aldosterone from the adrenal cortex. Aldosterone causes the tubules of the kidneys to increase the reabsorption of sodium and water into the blood.
The most reliable record of a Blue Shark at speed is 24.5 miles (39.4 kilometres) per hour for a 6.5-foot- (2-metre-) long individual. The Shortfin Mako (Isurus oxyrinchus) is probably the champion speedster among sharks.
What is the average speed of a shark?   In general, sharks swim at an average speed of five miles (8.25 kilometers) per hour, but when feeding or attacking, the average shark will reach speeds upwards of twel â¦ ve miles (19.25 kilometers) per hour... - ScienceDaily LLC     hope this helps.