<prompt> Which of the following statements about Histamine is true?Is found in mast cellsIncreases gastric acid secretionRelated to arousal and blood pressureAll of the above  <response>: Histamine is a physiologically active amine, C5H9N3, found in plant and animal tissue and released from mast cells as pa of the anallergic reaction in humans. It stimulates gastric secretion and causes dilation of capillaries, constriction of bronchial smooth muscle, and decreased blood pressure.Ref: Ganong;s review of medical physiology; 24th edition; page no: 149 