Diabetes Insipidus

1. Describe the mechanisms by which normal fluid regulation in the body occurs.

The kidneys remove extra body fluids from the bloodstream. These fluids are stored in the bladder as urine. If the fluid regulation system is working properly, the kidneys make less urine to conserve fluid when water intake is decreased or water is lost, for example, through sweating or diarrhea. The kidneys also make less urine at night when the body's metabolic processes are slower.

To keep the volume and composition of body fluids balanced, the rate of fluid intake is governed by thirst, and the rate of excretion is governed by the production of antidiuretic hormone (ADH), also called vasopressin. This hormone is made in the hypothalamus, a small gland located in the brain. ADH is stored in the nearby pituitary gland and released into the bloodstream when necessary. When ADH reaches the kidneys, it directs them to concentrate the urine by reabsorbing some of the filtered water to the bloodstream and therefore make less urine. Diabetes insipidus occurs when this precise system for regulating the kidneys' handling of fluids is disrupted

http://www.medicinenet.com/diabetes_insipidus/page2.htm

2. What is considered to be excessive thirst and urination in an adult?

An adult who urinates more than 50mL/kg body weight per 2 hours and an adult who drinks more than 4 quarts (1 gallon) or approximately 12 glasses (144 oz) of beverages per day.

3. List and briefly describe the four types of diabetes insipidus.

• Neurogenic Diabetes Insipidus- is caused by a deficiency of antidiuretic hormone

• Nephrogenic DI- is caused by insensitivity of the kidneys to effect the antidiuretic hormone

• Dispogenic DI- is caused by being really thirty and drinking way too much liquid of any kind.

• Gestagenic DI- is only during pregnancy and it is causd by a deficiency of the antidiuretic

4. In what ways is diabetes insipidus similar to diabetes mellitus? In what ways do they differ? Diabetes...