Pituitary Gland and Hypothalamus

A collection of vocabulary flashcards summarizing key concepts of the pituitary gland and hypothalamus based on lecture notes.

Pituitary gland

Controls several endocrine axes including growth and stress responses.

Hypothalamus

Region of the brain that regulates the pituitary gland and homeostatic functions.

Sella turcica

Bony structure that houses and protects the pituitary gland.

Anterior pituitary

Also known as adenohypophysis; controlled by hormones from the hypothalamus.

Posterior pituitary

Releases hormones such as ADH and oxytocin in response to neuronal signals.

ADH

Antidiuretic hormone, helps regulate water balance in the body.

Oxytocin

Hormone involved in childbirth, lactation, and social bonding.

Gonadotrophins

Stimulate the secretion of LH and FSH, important for sexual development.

Growth hormone

Stimulated by growth hormone releasing factor, important for tissue growth.

Prolactin

Hormone responsible for initiating and maintaining lactation.

Negative regulation of prolactin

Dopamine secretion decreases prolactin levels.

Pituitary adenoma

Tumor of the pituitary gland that can cause hormone imbalances.

Neurohypophysis

The posterior part of the pituitary gland, made from a downward extension of the brain.

ADH receptors

G-protein coupled receptors that mediate the actions of ADH.

Plasma osmolality

Concentration of solutes in plasma, normal range is 275-295 mosmol/kg.

Diabetes insipidus

Condition characterized by low ADH leading to excessive urination and thirst.

Starling forces

Physical forces that govern fluid movement between capillaries and tissues.

Oedema

Swelling caused by excess fluid in body tissues.

Polyuria

Excessive urination, often seen in diabetes insipidus.

Polydipsia

Excessive thirst, commonly associated with diabetes insipidus.

Cervix stretching

Stimulates the release of oxytocin during labor.

Milk ejection reflex

Oxytocin's role in breastfeeding; causes milk to be released.

Social bonding

Oxytocin is involved in forming emotional connections.

ADH receptor function impairment

Can occur due to diseases affecting the kidneys.

Hypophyseal portal system

Vascular connection transporting hormones from the hypothalamus to the anterior pituitary.

GnRH

Gonadotropin-releasing hormone, required for the secretion of FSH and LH.

Fertility

Can be affected by the levels and balance of pituitary hormones.

V1 receptors

ADH receptors mainly expressed in smooth muscle, causing vasoconstriction.

V2 receptors

ADH receptors mainly in the nephrons, enhancing water reabsorption.

Trust in social groups

Increased by the action of oxytocin.

Romantic attraction

Oxytocin plays a role in pair bonding and attraction.

Fatigue due to water retention

Can result from excessive ADH activity.

High plasma osmolality effects

Can lead to brain water loss and shrinkage.

Pituitary-hypothalamus axis

Complex feedback system regulating hormone secretion.

Increased TSH secretion from T4 tablets

False; T4 inhibits TSH due to negative feedback mechanism.

Role of hypothalamus in anterior pituitary

Regulates secretion of hormones based on feedback mechanisms.

Neuronal signals

Stimuli that trigger hormone release from the posterior pituitary.