ENDOCRINE EXAM 3 PATHO

What do hormones regulate?

Growth, development, metabolism, and mood stability.

How are hormones secreted?

At specific rates and often in a pulsatile manner.

What system do hormones operate within?

A feedback system.

What do hormones typically affect?

Target cells that have specific and appropriate receptors.

Which organs secrete hormones?

The kidneys.

Which organ deactivates hormones?

The liver.

What can cause abnormalities in endocrine function?

Elevated or depressed hormone levels.

What might cause abnormal hormone synthesis by a gland?

A disorder within the gland.

What is a possible reason for hormonal dysfunction related to feedback?

A faulty feedback system.

What does ectopic hormone production refer to?

Hormones produced outside their normal site of synthesis.

What issues can affect hormone transport in the bloodstream?

Defects in carrying hormones in the bloodstream.

What can cause target cells to fail to respond to hormones?

Surface receptor disorders.

What intracellular issues can affect hormone response in target cells?

Problems within the cell.

What forms the structure and functional basis for our neuroendocrine system?

Hypothalamic-Pituitary System

What connects the hypothalamus to the pituitary gland?

Pituitary stalk

How does the hypothalamus regulate anterior pituitary function?

By secreting releasing or inhibiting hormones and factors into the portal circulation

What hormone stimulates the secretion of prolactin?

Prolactin-releasing factor

What hormone inhibits prolactin secretion?

Prolactin-inhibiting factor

What does thyrotropin-releasing hormone (TRH) affect?

The release of thyroid hormones

What hormone stimulates the release of growth hormone (GH)?

Growth hormone-releasing hormone (GHRH)

What inhibits the release of growth hormone (GH) and thyroid-stimulating hormone (TSH)?

Somatostatin

What hormone facilitates the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH)?

Gonadotropin-releasing hormone (GnRH)

What hormone facilitates the release of adrenocorticotropic hormone (ACTH)?

Corticotropin-releasing hormone (CRH)

What does substance P do in relation to ACTH?

Inhibits ACTH release and stimulates the release of a variety of other hormones

What are the two portions of the pituitary gland?

Anterior and posterior portions

How are hormones of the anterior pituitary gland regulated?

By hypothalamic releasing factors, feedback from target organ hormones, and neurotransmitters

What hormones are produced by the anterior pituitary gland?

ACTH, MSH, GH, prolactin, FSH, LH, and TSH

What hormones does the posterior pituitary secrete?

Antidiuretic hormone (ADH) and oxytocin

What is the function of antidiuretic hormone (ADH)?

Controls serum osmolality, increases renal tubule permeability to water, and causes vasoconstriction in high doses

What are the functions of oxytocin?

Causes uterine contraction and lactation in women, and may aid in sperm motility in men

What is SIADH characterized by?

Abnormally high ADH secretion

What is diabetes insipidus characterized by?

Abnormally low ADH secretion

What do high ADH levels in SIADH cause?

Retention of excess free water

What are the consequences of SIADH?

Hyponatremia and hypoosmolality

What can cause SIADH?

Ectopic production of ADH by tumors, surgical procedures, pulmonary disorders, and central nervous system disorders

What is diabetes insipidus?

A condition caused by insufficiency of ADH leading to excessive loss of water in urine.

What are the two forms of diabetes insipidus?

1. Neurogenic (central type): insufficient secretion of ADH; 2. Nephrogenic: inadequate response to ADH.

What are the manifestations of diabetes insipidus?

Polyuria, nocturia, and constant thirst.

What is hypopituitarism?

A condition characterized by the absence or failure of anterior pituitary hormones.

What causes growth hormone (GH) deficiency in adults?

Increased body fat, decreased muscle mass, and psychological problems.

What is panhypopituitarism?

A condition where all hormones from the pituitary gland are deficient.

What are some causes of hypopituitarism?

Pituitary infarction, lesions, traumatic brain injury, gland removal, infections, and autoimmune conditions.

What are the symptoms of hypopituitarism?

Symptoms can range from mild to life-threatening, depending on the affected hormone.

What is hyperpituitarism?

A condition characterized by increased secretion of hormones from the pituitary gland.

What typically causes hyperpituitarism?

A slow-growing benign adenoma of the pituitary gland.

What are the effects of a pituitary adenoma?

Causes neurologic and secretory effects, including pressure-induced hyposecretion and visual disturbances.

What is acromegaly?

A condition caused by hypersecretion of growth hormone (GH).

What causes acromegaly?

Typically results from a pituitary adenoma leading to prolonged high levels of growth hormone.

What are the effects of acromegaly?

Proliferation of body and connective tissue, increased bone size, and potential renal, thyroid, and reproductive dysfunction.

What is giantism?

Hypersecretion of growth hormone in children before epiphyseal plates are closed.

What initiates the negative-feedback loop for the regulation of thyroid hormone?

TRH (Thyrotropin-Releasing Hormone)

Which glands are involved in the regulation of thyroid hormone?

Hypothalamus, anterior pituitary, and thyroid gland

What does TSH stimulate in the thyroid gland?

Secretion of thyroid hormone (TH) and uptake of iodine

What is necessary for the synthesis of thyroid hormone in the thyroid gland?

Iodine

What glycoprotein contains a precursor of thyroid hormone?

Thyroglobulin

What amino acid is a precursor for thyroid hormone?

Tyrosine

What do thyroid hormones control?

The metabolic rate of cells

How many lobes does the thyroid gland have?

Two lobes

Where is the thyroid gland located?

On either side of the trachea

What do the follicles in the thyroid gland secrete?

Some of the thyroid hormones

What do C cells in the thyroid gland secrete?

Calcitonin

What amino acid combines with iodine to form thyroid hormones?

Tyrosine

What are the two main thyroid hormones?

Thyroxine (T4) and Triiodothyronine (T3)

How are T3 and T4 transported in the bloodstream?

They are bound by carrier proteins in the plasma.

What is one effect of thyroid hormones on metabolism?

They alter protein synthesis and affect proteins, carbohydrates, lipids, vitamins, and other hormones.

What are the two types of alterations in thyroid function?

Primary and secondary

What causes primary thyroid disorders?

Dysfunction or disease of the thyroid, leading to an increase or decrease in thyroid hormone, and can be idiopathic

What are central (secondary) thyroid disorders?

Disorders of the pituitary gland where thyroid stimulating hormone is produced

What is thyrotoxicosis?

A condition due to any cause of increased thyroid hormone levels

What is hyperthyroidism?

Increased thyroid hormone levels from the thyroid gland

What is a common manifestation of hyperthyroidism related to heart rate?

Rapid Heart Rate (Tachycardia): The heart beats faster than normal, often exceeding 100 beats per minute.

What is a common symptom of hyperthyroidism related to weight?

Weight Loss: Despite increased appetite, individuals may experience unexplained weight loss.

What is a common manifestation of hyperthyroidism related to temperature sensitivity?

Increased Sensitivity to Heat: Feeling warm or hot even in cool environments.

What is a common symptom of hyperthyroidism related to shaking?

Tremors: Shaking or trembling, especially in the hands.

What psychological symptoms can occur with hyperthyroidism?

Anxiety and Nervousness: Feeling anxious, irritable, or easily agitated.

What is a common fatigue-related symptom of hyperthyroidism?

Fatigue: Despite increased energy levels, individuals may also experience fatigue.

How can hyperthyroidism affect menstrual cycles in women?

Irregular Menstrual Periods: Menstrual cycles may become lighter, more frequent, or irregular.

What hair-related symptoms can occur with hyperthyroidism?

Hair Loss or Brittle Hair: Some individuals may experience hair loss or thinning.

What is a physical manifestation of hyperthyroidism in the neck?

Swelling in the Neck (Goiter): The thyroid gland may enlarge, causing a visible swelling in the neck.

What eye problems can occur in individuals with Graves' disease?

Eye Problems (Graves' Ophthalmopathy): Bulging eyes, redness, or irritation.

What skin condition can be associated with hyperthyroidism?

Warm and Moist Skin: Skin may feel warm and moist to the touch.

What gastrointestinal symptom can occur with hyperthyroidism?

Frequent Bowel Movements: Changes in bowel habits, including diarrhea.

What is thyroid storm?

A life-threatening emergency characterized by severe thyrotoxicosis.

What are the symptoms of thyroid storm related to fever?

High Fever: A temperature between 104°F and 106°F (40°C to 41.1°C).

What is a cardiovascular symptom of thyroid storm?

Rapid Heart Rate: Heart rate exceeding 140 beats per minute.

What are signs of heart failure in severe cases of thyrotoxicosis?

Signs of heart failure, such as shortness of breath, swelling in the legs, and low blood pressure.

What changes can occur in mental status during thyroid storm?

Changes in Mental Status