Lec 1 Flashcards
(34 cards)
What is a hormone?
A chemical substance produced in the body that controls and regulates the activity of certain cells or organs.
How is the endocrine system regulated?
By feedback mechanisms similar to a thermostat regulating temperature.
What initiates the secretion of hormones regulated by the pituitary gland?
A releasing hormone signal sent from the hypothalamus to the pituitary gland.
What is the role of the anterior lobe of the pituitary gland?
Produces hormones regulated by the hypothalamus including growth hormone, TSH, ACTH, LH, FSH, and prolactin.
What is the function of growth hormone?
Stimulates growth of bone and tissue.
What condition results from growth hormone deficiency in adults?
Problems in maintaining proper amounts of body fat and muscle and bone mass.
What does thyroid-stimulating hormone (TSH) do?
Stimulates the thyroid gland to produce thyroid hormones.
Define hypothyroidism.
A lack of thyroid hormones due to a defect in the pituitary or the thyroid itself.
What is the role of adrenocorticotropin hormone (ACTH)?
Stimulates the adrenal gland to produce steroid hormones.
What do luteinizing hormone (LH) and follicle-stimulating hormone (FSH) control?
Sexual function and production of sex steroids (estrogen, progesterone, testosterone).
What is the function of prolactin?
Stimulates milk production in females.
What hormones are produced by the posterior lobe of the pituitary gland?
Antidiuretic hormone (vasopressin) and oxytocin.
What does antidiuretic hormone (ADH) control?
Water loss by the kidneys.
What is gigantism?
The childhood version of growth hormone excess before epiphyseal closure of long bone characterized by symmetrical overgrowth of body parts.
What is acromegaly?
A condition characterized by mandibular prognathism due to excess secretion of growth hormone after epiphyseal closure of long bone.
List some dental implications of hyperpituitarism.
- Hypertension
- Diabetes mellitus
- Hypercalcemia
- Hazards of general anesthesia
What is hypopituitarism?
A condition caused by compression or atrophy of anterior pituitary cells, resulting in pituitary dwarfism.
What is the most striking feature of pituitary dwarfism?
Short stature and low growth velocity for age.
What general manifestations are associated with hypopituitarism?
- Impaired growth (decreased GH)
- Hypoadrenocorticism (decreased ACTH)
- Hypothyroidism (decreased TSH)
- Failure of lactation (decreased prolactin)
- Failure of ovulation and defective spermatogenesis (decreased FSH and LH)
What is an adrenal crisis?
A medical emergency due to adrenal insufficiency that can occur from stress, trauma, or infection.
What are the causes of adrenal crisis?
- Adrenal insufficiency (Addison’s disease)
- Sudden withdrawal of exogenous steroids
- Surgical excision of the gland
- Pituitary insufficiency
What should be done to avoid adrenal crisis during dental procedures?
Supplementary corticosteroids should be given during periods of stress.
What is the role of cortisol in the body?
- Increases gluconeogenesis
- Increases lipolysis
- Maintains cardiovascular function
- Maintains skeletal muscle function
- Antagonizes the effect of insulin
What is the difference between primary and secondary adrenal insufficiency?
In primary, both glucocorticoid and mineralocorticoid functions are lost; in secondary, mineralocorticoid function is preserved.
