A 40-year-old woman was involved in an automobile accident in which she sustained severe head injuries. Following a slow but uneventful recovery, she was released from the hospital without any residual signs or symptoms. Six months later, the patient started to complain of frequency of micturition and was passing very large quantities of pale urine. She also said that she always seemed thirsty and would often drink 10 glasses of water in one morning. Using your knowledge of anatomy and physiology, do you think there is any connection between the urinary symptoms and her automobile accident?

Question

Quizplus · Accepted Answer

The Answer is Yes, there is a connection between the accident and the urinary symptoms. This patient is suffering from diabetes insipidus caused by traumatic damage either to the posterior lobe of the pituitary gland or to the supraoptic or paraventricular nuclei of the hypothalamus. In any event, production of vasopressin was inhibited. It should be pointed out that a lesion of the posterior lobe of the pituitary is usually not followed by diabetes insipidus, since the vasopressin (antidiuretic hormone) produced by the neurons of the supraoptic and paraventricular nuclei escapes directly into the bloodstream. The action of vasopressin is to increase nary content of catecholamines. What hormones are secreted by the cells of the suprarenal medulla, and what is their action?

A 40-Year-Old Woman Was Involved in an Automobile Accident in Which