Following a long history of facial and hand changes, Bill Brown was diagnosed with a somatropic adenoma. Adenoma refers to:

bone cartilage enlargement;

an endocrine tumour;

abnormally high levels of Growth Hormone;

A 22-year-old male is admitted to the intensive care unit with a closed head injury sustained in a motorcycle accident. The injury has caused severe damage to the posterior pituitary. Which of the following complications should be anticipated?

Dehydration from polyuria

Insufficient thyroid hormone production during pregnancy and childhood can result in:

cretinism

To adapt to high hormone concentrations, many target cells have the capacity for:

downregulation

Removal of the posterior pituitary would cause a decrease in the release of which hormone?

Antidiuretic hormone (ADH)

Antidiuretic hormone (ADH)

follicle-stimulating hormone;

Signs and symptoms of hypothyroidism are:

bradycardia, myxoedema and weight gain;

Bill was found to have abnormally high levels of Growth Hormone. An increase in growth hormone in adulthood results in:

acromegaly.

Diagnosis of Cushing’s disease includes:

striae, hyperglycemia, osteoporosis;

Insulin is primarily regulated by:

serum glucose levels;

Management of diabetes mellitus involves measuring glycated (glycosylated) haemoglobin (haemoglobin A₁c) levels. The purpose of this test is to:

monitor long-term serum glucose control;

Gabriel is likely to have an enlarged thyroid gland is known as goitre. In which thyroid states would goitre be found?

Hypothyroidism, Hyperthyroidism and Chronic iodine deficiency

A 54-year-old patient with pulmonary tuberculosis (lung infection) is evaluated for syndrome of inappropriate ADH secretion (SIADH). Which of the following electrolyte imbalances would be expected in this patient?

Hyponatraemia

Gabriel developed severe tachycardia, agitation and nausea. The nursing staff were concerned he had developed cardiac failure because:

hyperthyroidism is associated with increased metabolic rate, an increased cardiac output and possible atrial fibrillation which can lead to congestive heart failure.

An example for tertiary endocrine dysfunction is:

a tumour in the hypothalamus

Endocrine functions are

homeostasis, stress response, growth and development and sexual maturation.

Hormones are released

in response to an alteration in the cellular environment, to maintain a regulated level of certain substances or other hormones.

Regulation of hormones is mainly through

negative feedback.

Low levels of hormones cause

an increase in receptors on the cell known as up regulation.

High levels of hormones cause

a decrease in receptors on the cells known as down regulation.

Hormone receptors are located

in the plasma membrane or inside the target cell.

Protein based (water soluble) hormones

cannot cross the barrier require a messenger to cross.

Steroid based (lipid soluble) hormones

easily diffuse across the membrane

Endocrine dysfunction

Primary

Secondary

Tertiary

Primary endocrine dysfunction

malfunction of the gland producing the hormone

Secondary endocrine dysfunction

normal gland

abnormally releasing or stimulating gland (usually pituitary gland)

Tertiary endocrine dysfunction

problem with the hypothalamus and pituitary axis

usually caused by a tumor.

Anterior pituitary gland releases

growth hormone (GH)

thyroid stimulating hormone (TSH)

adrenocorticotropic hormone (ACTH)

follicle stimulating hormone (FSH)

luteinising hormone (LH)

Prolactin

Posterior pituitary gland releases

anti diuretic hormone (ADH)

Oxytocin

SIADH

syndrome of inappropriate antidiuretic hormone secretion.

increase secretion of ADH

causes increased renal water retension, hyponatraemia and hypo-osmolality.

Alterations if pituitary function include

diabetes insipidus

Diabetes insipidus

insufficent ADH

polyuria and polydypsia

partial or total inability to concentrate the urine

Pituitary tumors

Primary - adenoma

Secondary - metastatic lesions

functional - secrete pituitary hormones

nonfunctional - do not secrete hormones.

Decrease growth hormone causes

dwarfism

Increased growth hormone causes

gigantism

Somatotropin

used for treatment of GH deficiency

Somatostatin

used for treatment of excessive GH inhibits release of GH from hypothalamus

Excessive growth hormone in adults can cause

acromegaly

Type 1 diabetes mellitus is

destruction of insulin producing beta cells therefore no insulin produced.

Type 2 diabetes mellitus is

cellular resistance, insulin produced but target tissues are not responsive.

Gestational diabetes

diabetes during pregnancy due to hormonal changes associated with pregnancy

Metformin is used for

type 2 diabetes mellitus. It decreases glucose production, decreases glucose absorption in the gut and increases receptor sensitivity for insulin.

Thyroid produces

calcitonin - inhibits osteoclast activity reducing calcium within the blood.

Parathyroid produces

parathyroid hormone - increases osteoblast activity to increase calcium within the blood.

The hypothalamis is the coordinating center of the brain for

the endocrine, behavioural and autonomic nervous system function

Primary defects in the endocrine function originate in

the target gland responsible for producing the hormone.

Hypofunction of the pituitary gland results in

short stature

An overactive thyroid gland results in

a higher metabolism.

What hormone is central to the maintenance of body metabolism, growth and development in children?

Thyroid hormone.

What hormone has multiple roles including anti-insulin effects, the length of linear bones and the rate of cell division.

Growth hormone.

When hormones act locally on cells other than those that produced the hormone, the action is called

paracrine.

When a hormone acts on the cell that produced it

autocrine

Goitre is

a visible increase in size of the thyroid gland and can be caused by either hyperthyroidism or hypothyroidism.