Question

1. Discuss the negative feedback system of the endocrine system. Describe what actions cause the feedback system to be initiated and shut off.

3. Describe the pathophysiology, clinical manifestations, diagnostic test, complications and treatment of pituitary, thyroid, parathyroid, pancreatic and adrenal endocrine disorders. (Graves' disease, Addison's disease, acromegaly, gigantism, dwarfism, adrenal insufficiency, SIADH, diabetes, thyrotoxicosis, myexedema, diabetes insipitus, Cushing's disease/syndrome, somogyi, dawn phenomenon

Answer 1

1. There are two types of feedback mechanism positive feed back mechanisam and negative feedback mechanismNegative feedback mechanism of endocrine system

Negative feedback decreases the deviation from an ideal normal value and is important in maintaining homeostasis .most endocrine glands are under the control of negative feedback mechanism.  

Example ; negative feedback is the regulation of calcium level.parathyroid hormone which regulate blood calcium amount.when calcium decrease,parathyroid gland sense the decrease and secrete more parathyroid hormone.it help to release the calcium from the bone and increases the calcium uptake in to the blood stream from the collecting tubules in the kidney. Ifblood calcium level increase to much parathyroid hormone production will decrease. Which help to stop release of calcium from bones .neuroendocrine systems and hormonal system which help to .initiate and stop action.

3. Pathophysiology of endocrine disorders.

It occurs when the glands function variates from the normal.Hyperfunction of endocrine glands which is characterized by increased secretion of its hormone as well as by increased concentration of this hormone circulating blood.hypofunction of endocrine glands occurs because of decreased secretion of its hormone as well as decreased concentration of this hormone in circulating blood. Endocrine disorders results when a gland produces too much or too little of an endocrine hormone is called hormone imbalances.

Clinical manifestations.

• Fatigue,
• Stomach upset
• dehydration
• Skin changes
• Weight loss.
• Tremors
• Anxiety .
• Rapid heartbeat

Diagnostic tests

• Ct scan
• Dual energy x ray absorptiometry.
• Ultrasound.
• Fine needle aspirations.
• Lab tests

Complications

• Growth retardation
• Delayed puberty.
• Fertility disorders.
• Impaired carbohydrates metabolism
• Sjogren syndrome.
• Anorexia nervosa.

Treatment

• Medications
• Surgery
• Hormone replacement
• Radioactive iodine treatment or removal for thyroid gland.