Quiz 17: Review of the Central Nervous System
Peripheral Nervous System (PNS): The peripheral nervous system is the part of nervous system, which exists outside the brain and spinal cord. The nerves in the PNS, connects the central nervous system (CNS) and the sensory organs. The two divisions of Peripheral Nervous System (PNS) are listed below. 1. Somatic Division. 2. Autonomic Division. The primary functions of the Somatic and Autonomic division of the PNS are listed below. Somatic Division: The somatic division of nervous system, provides the voluntary control over the skeletal muscles. Autonomic Division : The autonomic division of nervous system provides the involuntary control over the gastrointestinal, Cardiovascular, Respiratory and the urinary systems. The major vital activities of Autonomic division of Nervous system are listed below. • Contraction of the cardiac muscle. • Contraction of smooth muscles of the gastrointestinal tract, bronchi, blood vessels and urinary tract. • Secretion of saliva, sweat, bronchial and gastric secretions.
Dopamine is a neurotransmitter, which is also a vasopressor. So, dopamine can be used for treating the low blood pressure, and shock. Dopamine is a naturally occurring Catecholamine, which exhibits both alpha and beta adrenergic agonist activity. The low doses of the dopamine can stimulate the dopaminergic receptors, and produces the vasodilation, especially in the kidneys. The vasodilation in the kidneys, increases the renal blood flow, and promotes the urine output. The higher doses of dopamine, induces the heart to beat more, which is helpful to increase the cardiac output, during the situations of cardiogenic and hypovolemic shocks. Note: Cardiogenic shock: The cardiogenic shock is a sudden condition, in which the heart cannot pumps the enough blood to our body's requirement. Hypovolemic Shock: The hypovolemic shock is the condition, where the body loses more than 20 percent of blood or fluid supply. Hence, the indications for the dopamine therapy includes the low blood pressure, hypovolemic and cardiogenic shock. In addition, the dopamine is, also used to improve both kidneys and heart functions.
Fight or Flight response: The Fight or Flight response is a physiological action occurred during the unexpected attacks. The autonomic nervous system prepares the physiologic functions in the body, to face the unexpected attacks. The major symptoms of Fight-or-Flight Response are listed below. • Increased heart rate. • Increased blood pressure. • Increased mental alertness. • Broncho-dilation. • Pupil Dilation. • Increased perspiration. • Increased muscle tense.