Pituitary Gland and Hormones
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Questions and Answers

What symptoms are associated with pituitary prolactinoma in women and men due to hormonal imbalance? select all that apply

  • Infertility problems in women (correct)
  • Osteoporosis (correct)
  • Gynecomastia in men (correct)
  • Galactorrhea in both genders (correct)

What is the primary treatment for a macroadenoma?

  • Dopamine agonists
  • Surgical resection (correct)
  • Radiation therapy
  • Hormonal replacement therapy

Central diabetes insipidus is primarily related to which of the following?

  • Excessive ADH secretion
  • Kidney dysfunction
  • Hormonal imbalance
  • Reduced ADH secretion (correct)

Which condition is characterized by water intoxication and dilutional hyponatremia?

<p>SIADH (A)</p> Signup and view all the answers

In patients with nephrogenic diabetes insipidus, what is primarily affected?

<p>Kidney's response to ADH (C)</p> Signup and view all the answers

What is the primary function of vasopressin, also known as ADH?

<p>Increase water reabsorption/excretion in the kidneys (B)</p> Signup and view all the answers

Which hormones are synthesized in the hypothalamus but stored in the posterior pituitary?

<p>ADH and oxytocin (D)</p> Signup and view all the answers

Which of the following hormones are categorized as tropic hormones?

<p>FLAT = FSH, LH, Adrenocorticotropic hormone, thyroid stimulating hormone (C)</p> Signup and view all the answers

What defines the hypothalamic-pituitary portal system?

<p>It carries hypothalamic releasing and inhibiting hormones to the anterior pituitary. (D)</p> Signup and view all the answers

Which of the following statements about the posterior pituitary is correct?

<p>It secretes hormones directly in response to nerve signals from the hypothalamus. (A)</p> Signup and view all the answers

Which hormone is specifically associated with promoting mammary gland development and lactation?

<p>Prolactin (D)</p> Signup and view all the answers

Which anterior pituitary cell type is responsible for the secretion of thyroid-stimulating hormone (TSH)?

<p>Thyrotropes (C)</p> Signup and view all the answers

Where are the magnocellular neurons that secrete oxytocin primarily located?

<p>Paraventricular nucleus (5/6) (B)</p> Signup and view all the answers

Which of the following hormones is NOT regulated by releasing hormones from the hypothalamus?

<p>Oxytocin (B)</p> Signup and view all the answers

From which embryonic structure does the posterior pituitary (neurohypophysis) originate?

<p>Hypothalamus (C)</p> Signup and view all the answers

Which of the following is a major physiological role of endorphins released from the anterior pituitary?

<p>Pain relief, sense of well-being (D)</p> Signup and view all the answers

What is the anatomical location of the pituitary gland?

<p>In the sella turcica of the sphenoid bone below the hypothalamus (D)</p> Signup and view all the answers

How is prolactin secretion primarily inhibited?

<p>By dopamine, which acts as a prolactin-inhibiting factor (D)</p> Signup and view all the answers

What type of hormones does the pituitary release?

<p>Peptide hormones, which are short chains of amino acids (D)</p> Signup and view all the answers

What structure connects the posterior pituitary to the hypothalamus?

<p>Hypophysial stalk (D)</p> Signup and view all the answers

What distinguishes the adenohypophysis (anterior pituitary) the neurohypophysis (posterior pituitary)?

<p>The adenohypophysis develops from epithelial cells of Rathke's pouch while the neurohypophysis develops from neural tissue (B)</p> Signup and view all the answers

Which of the following characteristics is true of the anterior pituitary?

<p>It is highly vascular and consists of epithelial cells. (D)</p> Signup and view all the answers

What is the primary effect of growth hormone?

<p>Stimulates growth of all cells in the body (D)</p> Signup and view all the answers

The secretion of ADH is increased in response to which condition?

<p>Decreased blood volume (D)</p> Signup and view all the answers

What initiates a positive feedback loop in prolactin release?

<p>Infant breastfeeding so more milk is produced which causes infant to drink more (C)</p> Signup and view all the answers

What effect does elevated T3 and T4 levels have on TSH secretion?

<p>Inhibits TSH secretion (D)</p> Signup and view all the answers

Which type of adenoma is most commonly associated with prolactin excess?

<p>Functional adenoma - secrete hormones (D)</p> Signup and view all the answers

Which sign is characterized by pain or resistance when the leg is straightened at the knee while the hip is flexed at 90°?

<p>Kernig sign (C)</p> Signup and view all the answers

What primarily distinguishes gigantism from acromegaly?

<p>Gigantism occurs due to excess GH during adolescence while acromegaly occurs post-adolescence (B)</p> Signup and view all the answers

In acromegaly, why should nasal intubation be avoided?

<p>Enlarged turbinates causing obstruction (B)</p> Signup and view all the answers

Which condition is directly caused by excess secretion of ACTH from a pituitary tumor?

<p>Cushing's disease (A)</p> Signup and view all the answers

What is a potential complication associated with Cushing's syndrome during anesthesia? select all that apply

<p>Increased risk of deep vein thrombosis/ PE (A), Difficult airway management due to OSA and buffalo hump (B), Avoid etomidate (C), Increased risk of infection, hyperglycemia (D)</p> Signup and view all the answers

What is the lowest part of the hypothalamus that connects with the pituitary stalk?

<p>Median eminence (A)</p> Signup and view all the answers

What structure separates the anterior and posterior pituitary?

<p>Pars intermedia (A)</p> Signup and view all the answers

What is the difference between exocrine and endocrine glands?

<p>Exocrine glands have ducts that carry their secretions to a surface, while endocrine glands secrete hormones directly into the bloodstream. (B)</p> Signup and view all the answers

Where are the inhibiting and releasing hormones that directly affect anterior pituitary hormones secreted?

<p>Hypothalamus (B)</p> Signup and view all the answers

What is the only hormone secreted by the anterior pituitary that is mediated by positive feedback?

<p>Prolactin (A)</p> Signup and view all the answers

______ hormones from the hypothalamus play a predominant role in the secretion of anterior pituitary hormones with the exception of prolactin.

<p>Releasing (B)</p> Signup and view all the answers

What mediates the releasing and inhibiting factors being released from the hypothalamus?

<p>Negative feedback (B)</p> Signup and view all the answers

What subtype of hormones secreted from the hypothalamus plays the greatest role in the regulation of anterior pituitary hormones?

<p>Releasing hormones (B)</p> Signup and view all the answers

Match the following anterior pituitary hormones with their functions:

<p>FSH = Stimulates ovulation and spermatogenesis LH = Corpus luteum development and release of sex hormones Adrenocorticotropic hormone = Secretion of adrenocortical hormones TSH = Controls secretion rate of T4 and T3 Prolactin = Mammary gland development and milk production Growth hormone = Growth, protein formation, cell multiplication and differentiation Melanocyte stimulating hormone = Increases skin melanin</p> Signup and view all the answers

How are hormones transported from the hypothalamus to the anterior pituitary?

<p>Through the bloodstream via the hypophyseal portal system (A)</p> Signup and view all the answers

How are hormones transported to the posterior pituitary?

<p>Via axonal transport along nerve fibers originating in the hypothalamus (B)</p> Signup and view all the answers

Which of the following act as inhibiting factors for ACTH (adrenocorticotrophic hormone)? (Select all that apply)

<p>Cortisol (A), Norepinephrine (B)</p> Signup and view all the answers

What is the growth hormone inhibiting factor?

<p>Somatostatin (C)</p> Signup and view all the answers

Which of the following hormones act as inhibiting factors for gonadotrophic hormones (FSH and LH)? select all that apply

<p>Testosterone (A), Progesterone (B), Estrogen (C), Inhibin (D)</p> Signup and view all the answers

Which part of the pituitary gland is primarily comprised of neural tissue from glial-like pituicytes?

<p>Neurohypophysis (posterior pituitary) (B)</p> Signup and view all the answers

Where are the hormones synthesized that are secreted by the posterior pituitary?

<p>Hypothalamus (C)</p> Signup and view all the answers

Where are the magnocellular neurons that secrete ADH primarily located?

<p>Supraoptic nuclei (5/6) (A)</p> Signup and view all the answers

How are posterior pituitary hormones and acetylcholine similar?

<p>Both are released via exocytosis in response to a nerve impulse. (C)</p> Signup and view all the answers

Where are the paraventricular and supraoptic nuclei found?

<p>Hypothalamus (C)</p> Signup and view all the answers

What is a magnocellular neuron?

<p>A type of neuron that has large cell bodies and is primarily involved in the synthesis of hormones in the supraoptic and paraventricular nuclei in the hypothalamus. (A)</p> Signup and view all the answers

What is the main difference between tropic hormones and direct hormones?

<p>Tropic hormones stimulate other glands to release hormones, while direct hormones act directly on target organs. (A)</p> Signup and view all the answers

Which of the following are direct hormones released from the adenohypophysis (anterior pituitary)? select 3 and remember FLAT-PEG

<p>Prolactin (A), Endorphin (B), Growth Hormone (C)</p> Signup and view all the answers

What types of hormones are ADH and oxytocin?

<p>Direct hormones that target other organs (B)</p> Signup and view all the answers

Which of the following structures are close neighbors to the pituitary gland and can cause vision loss due to mass effect from a tumor?

<p>Both optic nerve and optic chiasm (C)</p> Signup and view all the answers

What stimulates adrenocorticotropic hormone (ACTH) release? (Select all that apply)

<p>Corticotropin-releasing hormone (CRH) (A), Stress (B), Dopamine (C), Serotonin (D), Acetylcholine (E), Histamine (F)</p> Signup and view all the answers

What is the hypothalamic-pituitary-adrenal axis?

<p>A complex network between the hypothalamus, pituitary, and adrenal glands that regulates stress response and hormone release. (A)</p> Signup and view all the answers

What is the function of TSH (Thyroid Stimulating Hormone)?

<p>Stimulation of the thyroid to release T4, T3, and calcitonin (A)</p> Signup and view all the answers

What are the expected laboratory findings for a patient with hyperthyroidism?

<p>Decreased TSH (compensatory) and increased free T4 (B)</p> Signup and view all the answers

Which of the following stimulates the release of endorphins? (Select all that apply)

<p>Pain (A), Stress (B), Exercise (C), Sex (D)</p> Signup and view all the answers

Which neurotransmitter is known to inhibit endorphins?

<p>GABA (C)</p> Signup and view all the answers

Why does GABA inhibit endorphins?

<p>To modulate the euphoria from endorphins (B)</p> Signup and view all the answers

What causes the secretion of ADH (antidiuretic hormone)?

<p>Both increased osmolarity and decreased circulating blood volume (C)</p> Signup and view all the answers

Which of the following statements is true regarding pituitary adenomas?

<p>They are common and most are benign. (B)</p> Signup and view all the answers

What are the classic characteristics of a functional adenoma? (Select all that apply)

<p>Increased hormone secretion (A), Microadenoma size (B)</p> Signup and view all the answers

What are the classic characteristics of a non-functional adenoma? (Select all that apply)

<p>Does not secrete hormones (A), Causes symptoms due to local mass effects (B), Macroadenoma (D)</p> Signup and view all the answers

What is panhypopituitarism characterized by?

<p>All of the above (D)</p> Signup and view all the answers

What is a result of the stalk effect due to a macroadenoma?

<p>Hyperprolactinemia due to disruption of dopamine on inhibiting prolactin secretion (B)</p> Signup and view all the answers

What is bitemporal hemianopsia?

<p>Loss of vision in both outer fields of vision (A)</p> Signup and view all the answers

What is pituitary apoplexy?

<p>A condition caused by a rupture of the pituitary gland, usually due to bleeding. (A)</p> Signup and view all the answers

What is Sheehan's syndrome?

<p>A condition where anterior pituitary is damaged due to significant blood loss during or after childbirth (A)</p> Signup and view all the answers

What is Brudzinski's sign?

<p>A reflex that causes hip flexion when the neck is flexed (A)</p> Signup and view all the answers

What should be considered in the anesthetic management of a patient with an impaired adrenal axis?

<p>Stress dose of glucocorticoids (A)</p> Signup and view all the answers

What are the complications related to the anesthetic management of a patient with growth hormone excess (e.g., gigantism or acromegaly)?

<p>Difficult airway (mask, laryngoscopy, and intubation) (A), Subglottic stenosis so need smaller ETT (B), Cardiomyopathy (C), Diabetes Mellitus (DM) (D), Hypertension (HTN) (E)</p> Signup and view all the answers

What is a potential result of decreased growth hormone (GH) levels?

<p>Dwarfism (B)</p> Signup and view all the answers

What is panhypopituitarism?

<p>A rare condition that occurs when the pituitary gland stops producing most or all of its hormones. (B)</p> Signup and view all the answers

What causes Cushing's disease? select all that apply

<p>Functioning pituitary microadenoma (A), Adrenal gland tumor (B), Ectopic ACTH syndrome (C), Primary adrenal insufficiency (D)</p> Signup and view all the answers

What are the causes of Cushing's syndrome? (Select all that apply)

<p>Excess ACTH (A), Adrenal cancers (B), Excess iatrogenic administration (C), Non-pituitary tumors secreting ACTH (D)</p> Signup and view all the answers

Which of the following are symptoms associated with Cushing's syndrome? (Select all that apply)

<p>Hyperglycemia and HTN (A), Moon face and buffalo hump (B), Weight gain, central obesity (C), Alkalosis and hypokalemia (D)</p> Signup and view all the answers

What is the most common pituitary hypersecretion syndrome?

<p>Pituitary prolactinoma (A)</p> Signup and view all the answers

What is the first-line treatment for microprolactinomas?

<p>Dopamine agonists (C)</p> Signup and view all the answers

How are gonadotrophic adenomas usually first identified?

<p>From mass effect symptoms (A)</p> Signup and view all the answers

What is the treatment for Diabetes Insipidus (DI)?

<p>DDAVP and maintain intravascular volume (A)</p> Signup and view all the answers

What is the expected serum and urine osmolality if a patient has Diabetes Insipidus (DI)?

<p>High serum osmolality and low urine osmolality (B)</p> Signup and view all the answers

What is the expected serum and urine osmolality if a patient has SIADH?

<p>Low serum osmolality and high urine osmolality (B)</p> Signup and view all the answers

When should hypertonic saline be administered for a patient with SIADH?

<p>Severe or symptomatic hyponatremia (&lt;120) (B)</p> Signup and view all the answers

Why do we slowly correct sodium balance?

<p>To prevent osmotic demyelination syndrome (A)</p> Signup and view all the answers

When do we administer DDAVP to patients with diabetes insipidus (DI)?

<p>If urine output is &gt; 300 ml/hour for &gt; 2 hours (A)</p> Signup and view all the answers

What is the indication for a Transsphenoidal Hypophysectomy?

<p>Microadenomas (A)</p> Signup and view all the answers

How are macroadenomas managed surgically if they are too big for a transsphenoidal hypophysectomy?

<p>Open craniotomy (B)</p> Signup and view all the answers

What anesthetic complications are associated with untreated hypothyroidism? (Select all that apply)

<p>Increased sensitivity to narcotics and barbiturates (A), Prolonged emergence (B), Myxedema coma (C)</p> Signup and view all the answers

What anesthetic complications are associated with untreated adrenal insufficiency?

<p>All of the above (D)</p> Signup and view all the answers

What anesthetic complications are associated with acromegaly and Cushing's syndrome? (Select all that apply)

<p>Increased risk of hypertension (A), Increased risk of diabetes (B), Increased risk of cardiovascular disease (C), Electrolyte abnormalities (D), Difficult airway (E)</p> Signup and view all the answers

Why is it important to have large bore IVs for a Transsphenoidal Hypophysectomy?

<p>To accommodate potential blood loss from the internal carotid artery, which is close to the pituitary. (A)</p> Signup and view all the answers

What is the correct position used for a transsphenoidal hypophysectomy?

<p>Supine with head elevated 10-20 degrees in Mayfield clamp, BUE padded and tucked (B)</p> Signup and view all the answers

What is a contraindication during a Transsphenoidal Hypophysectomy? select 3

<p>Use of nitrous oxide (A), Hyperventilation intraoperatively - vasoconstriction making pituitary harder to access (C), Positive pressure ventilation (PPV) postextubation due to pneumocephalus - NO CPAP (B)</p> Signup and view all the answers

What specialized tube can be used during a Transsphenoidal Hypophysectomy?

<p>Oral RAE (A)</p> Signup and view all the answers

What is the maneuver used to switch out an endotracheal tube (ETT) for a laryngeal mask airway (LMA) to promote a smooth emergence?

<p>Bailey's maneuver (C)</p> Signup and view all the answers

What is the stalk effect?

<p>It refers to elevated levels of prolactin due to damage of the pituitary stalk (infundibulum) (B)</p> Signup and view all the answers

What condition is bitemporal hemianopsia associated with?

<p>Lesions affecting the optic chiasm (A)</p> Signup and view all the answers

Flashcards

Pituitary gland

Small gland at the base of the brain, located in the sella turcica of the sphenoid bone.

Adenohypophysis

Anterior pituitary; embryonically from Rathke's pouch, highly vascular.

Neurohypophysis

Posterior pituitary, receives hormones from the hypothalamus.

Hypothalamic-hypophysial portal vessels

Specialized blood vessels connecting hypothalamus to anterior pituitary to carry hypothalamic hormones.

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Prolactin secretion

Regulation by prolactin-inhibiting factors (PIFs) like dopamine and stimulatory mechanisms like TRH and oxytocin.

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Hormones (types)

Peptide (amino acid chains), Amine (tyrosine derivatives), and Steroid (cholesterol-derived).

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Hypothalamic-hypophysial stalk

Connects the posterior pituitary to the hypothalamus.

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Median eminence

Lowest part of hypothalamus, connection to pituitary stalk.

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Hypothalamus role in hormone release

The hypothalamus releases hormones that control most other hormones except prolactin, which is regulated by positive feedback.

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Anterior Pituitary hormones

FSH, LH, ACTH, TSH, prolactin, endorphins, growth hormone, and melanocyte-stimulating hormone are produced by the anterior pituitary.

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Anterior Pituitary cell types

Different cell types within the anterior pituitary produce specific hormones. For example, somatotropes make growth hormone.

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Posterior Pituitary (Neurohypophysis)

The posterior pituitary is part of the neural tissue and stores and releases hormones made in the hypothalamus.

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ADH function

Antidiuretic hormone (ADH) regulates water excretion in urine and prevents dehydration.

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Oxytocin function

Oxytocin is involved in milk production (lactation) and childbirth (labor/delivery).

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Posterior Pituitary regulation

Posterior pituitary hormone release is exocytotic, unlike the anterior pituitary, which is regulated by releasing hormones from the hypothalamus.

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Hypothalamic origin of 'releasing' hormones

A prefix 'releasing' in a hormone name means the hormone originated from the hypothalamus

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Posterior Pituitary Hormone Release

Synthesized in the hypothalamus, transported to and released from the posterior pituitary via nerve signals.

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Anterior Pituitary Hormone Regulation

Controlled by hypothalamic releasing and inhibiting hormones via the hypothalamic-pituitary portal system.

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FLAT-PEG Mnemonic

A helpful acronym for remembering anterior pituitary tropic hormones: FSH, LH, ACTH, TSH. PEG stands for prolactin, endorphin, growth hormone, which are direct acting hormones.

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Hypothalamic-Pituitary-Adrenal (HPA) Axis

A crucial endocrine pathway involving the hypothalamus, pituitary, and adrenal glands.

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Negative Feedback Loops (Hormones)

The majority of hormones are regulated by negative feedback loops, except prolactin.

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What stimulates cortisol secretion?

The hypothalamic-pituitary-adrenal (HPA) axis, specifically corticotropin-releasing hormone (CRH) from the hypothalamus, stimulates the anterior pituitary to release adrenocorticotropic hormone (ACTH), which in turn targets the adrenal glands to secrete cortisol.

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What inhibits cortisol secretion?

Cortisol itself, through negative feedback, inhibits its own production by reducing the release of CRH and ACTH. This helps to maintain proper cortisol levels.

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What stimulates TSH release?

Thyrotropin-releasing hormone (TRH) from the hypothalamus stimulates the anterior pituitary to release TSH.

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What inhibits TSH release?

High levels of T3 and T4, the thyroid hormones, inhibit the release of TSH through negative feedback. This ensures the thyroid doesn't overproduce hormones.

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Prolactin's role

Prolactin stimulates the development of breasts and the production of milk in lactating females. It plays a role in maternal care and bonding.

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What stimulates prolactin release?

Prolactin-releasing hormone (PRH) from the hypothalamus stimulates the anterior pituitary to release prolactin.

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What inhibits prolactin release?

Dopamine, also known as prolactin-inhibiting hormone (PIH), inhibits the release of prolactin from the anterior pituitary.

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Endorphins function

Endorphins act as natural painkillers, reduce stress, improve mood, and enhance feelings of well-being. They play a role in reward and pleasure.

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What stimulates endorphin release?

Stress, pain, exercise, and sexual activity trigger the release of endorphins.

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Prolactinoma

A benign tumor of the pituitary gland that produces excess prolactin. This can cause symptoms like galactorrhea (breast milk production) and infertility in women and decreased sex drive and gynecomastia in men.

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Prolactinoma Treatment

Treatment for prolactinomas depends on the size. Microadenomas are usually treated with dopamine agonists (medicines), while macroadenomas may require surgical removal.

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OB hemorrhage

Emergency condition requiring surgical decompression, steroid therapy, and hormone replacement for treatment.

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Diabetes Insipidus (DI)

A condition where the body doesn't produce enough antidiuretic hormone (ADH), leading to excessive urination and dehydration.

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Brudzinski sign

Involuntary bending of the knees and hips when the neck is flexed, indicating meningeal irritation.

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Kernig sign

Pain or resistance when straightening the leg at the knee while the hip is flexed, indicating meningeal irritation.

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SIADH (Syndrome of Inappropriate Antidiuretic Hormone)

A condition where the body produces too much ADH, leading to water retention and low sodium levels.

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SIADH Treatment

SIADH treatment focuses on correcting the underlying cause and limiting fluids. In severe cases, hypertonic saline may be given to increase sodium levels.

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Gigantism

Excessive growth in height due to excessive growth hormone (GH) before bone growth plates seal.

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Acromegaly

Abnormal bone thickening and growth after bone growth plates seal due to excessive GH.

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Dwarfism

Insufficient bone maturation and short stature due to congenital deficiency in growth hormone.

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Panhypopituitarism

Insufficient production of all pituitary hormones, leading to developmental delays and lack of adult sexual function.

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Cushing's disease

Excessive ACTH production from a pituitary tumor, leading to increased cortisol release and Cushingoid symptoms.

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Cushing's syndrome

Excess glucocorticoid levels due to various causes, including ACTH excess, adrenal tumors, or iatrogenic administration.

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Pituitary prolactinoma

The most common pituitary hypersecretion syndrome in both men and women, characterized by excess prolactin.

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Study Notes

Pituitary Gland

  • The pituitary gland, also known as the hypophysis, is a small gland located in the sella turcica of the sphenoid bone, below the hypothalamus.
  • It connects with the hypothalamus via the hypophysial stalk (pituitary stalk).
  • The pituitary gland is divided into the anterior pituitary (adenohypophysis) and the posterior pituitary (neurohypophysis).
  • The anterior and posterior pituitary are separated by the pars intermedia.
  • Endocrine glands release hormones directly into the bloodstream.
  • Exocrine glands release hormones into ducts.

Hormone Types

  • Peptide hormones are short chains of amino acids. All pituitary hormones are peptides.
  • Amine hormones are derived from tyrosine.
  • Steroid hormones are derived from cholesterol.

Anterior Pituitary (Adenohypophysis)

  • Originates embryonically from Rathke's pouch, composed of epithelial cells.
  • Highly vascular, the hypothalamus secretes hormones that control anterior pituitary secretion.
  • Hypothalamic releasing hormones (e.g., TRH) and hypothalamic inhibiting hormones (e.g., dopamine) regulate the anterior pituitary via hypothalamic-hypophysial portal vessels.
  • Prolactin secretion is primarily regulated by prolactin-inhibiting factors (PIFs), and stimulatory mechanisms, such as thyrotropin-releasing hormone (TRH) and oxytocin. Estrogen plays a role in stimulating prolactin secretion, especially during pregnancy.

Posterior Pituitary (Neurohypophysis)

  • Originates embryonically from an outgrowth of the hypothalamus.
  • It is composed of neural tissue and pituicytes.
  • The hypothalamus synthesizes ADH and oxytocin.
  • These hormones travel along axons to the posterior pituitary, where they are stored and directly released into the bloodstream.

Pituitary Hormones

  • Various anterior pituitary hormones, like follicle-stimulating hormone (FSH), luteinizing hormone (LH), adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH), prolactin, endorphins, growth hormone, and melanocyte-stimulating hormone (MSH) have specific functions.
  • Posterior pituitary hormones include antidiuretic hormone (ADH) and oxytocin, which regulate body functions like water balance and childbirth.

Hypothalamic-Pituitary Axis

  • Stimulating and inhibiting hormones from the hypothalamus regulate anterior pituitary hormone secretion.

Pituitary Cell Types and Hormones

  • Corticotropes: ACTH
  • Somatotropes: Growth hormone
  • Thyrotropes: TSH
  • Lactotropes: Prolactin
  • Gonadotropes: FSH and LH

Posterior Pituitary Cell Types

  • Magnocellular neurons: secret ADH and oxytocin.

Posterior and Anterior Pituitary

  • The posterior pituitary releases hormones produced by the hypothalamus.
  • The anterior pituitary releases its own specific hormones that are regulated by hormones from the hypothalamus.

Regulation of Hormones

  • Negative feedback: hormones from target organs regulate hypothalamus and pituitary function (except prolactin which has positive feedback).
  • Specific factors (like TRH & dopamine), and others regulate prolactin secretion.
  • Hormones are regulated by hypothalamic releasing and inhibiting hormones.

Pituitary Tumors

  • Adenomas are common pituitary tumors, often benign.
  • Functional adenomas secrete hormones, causing symptoms related to excess hormone production.
  • Non-functional adenomas cause mass effects due to increased size, causing symptoms like headaches, visual field problems, and diabetes insipidus or other syndromes.

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Pituitary Gland - Lesson 13 PDF

Description

This quiz covers the anatomy and functions of the pituitary gland, including the types of hormones it produces. Explore the differences between the anterior and posterior pituitary as well as the various hormone categories like peptide, amine, and steroid hormones. Test your knowledge on this crucial part of the endocrine system.

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