Lab 4: Endocrine System, Hormonal Pathways, and Disorders

Endocrine System

Glands and organs that secrete hormones to regulate various physiological processes.

Hypothalamus

Links the nervous and endocrine systems; releases hormones that regulate the pituitary.

Pituitary Gland

Often called the 'master gland,' it releases hormones that control other endocrine glands.

Thyroid Gland

Regulates metabolism through the secretion of thyroid hormones (T3, T4).

Adrenal Glands

Release hormones like cortisol, aldosterone, and adrenaline to manage stress, metabolism, and sodium balance.

Pancreas

Regulates blood glucose through insulin and glucagon.

Gonads

Testes and ovaries that produce sex hormones responsible for reproduction and secondary sexual characteristics.

Negative Feedback

A process where the release of a hormone is inhibited by its own action or by a product of the pathway.

Positive Feedback

A mechanism where the release of a hormone stimulates further release of that hormone, amplifying the response.

Addison's Disease

A condition characterized by insufficient production of cortisol and sometimes aldosterone from the adrenal glands.

Graves’ Disease

An autoimmune disorder where the body produces antibodies that stimulate the thyroid gland to release excess thyroid hormones.

HGT Axis

Hypothalamic-Gonadal-Thyroid axis involved in regulating metabolism, growth, and development.

HPA Axis

Hypothalamic-Pituitary-Adrenal axis that regulates stress response, immune suppression, glucose metabolism, and inflammation.

HPG Axis

Hypothalamic-Pituitary-Gonadal axis involved in regulating reproductive function and secondary sexual characteristics.

Hormonal Imbalance

A condition where there is too much or too little of a hormone in the body, affecting various physiological processes.

Castration

The removal of gonads, impacting hormonal feedback and organ size.

Weight Loss

A symptom potentially linked to hyperthyroidism or excess cortisol that increases metabolism.

Hyperthermia

Excess body temperature often seen with increased thyroid hormone levels affecting metabolic rates.

Anxiety

A symptom that may be linked to excess cortisol or thyroid hormones affecting the nervous system.

Increased Heart Rate

Typically associated with hyperthyroidism, which raises the body's metabolic rate.

TRH

Thyrotropin-releasing hormone released by the hypothalamus.

TSH

Thyroid-stimulating hormone released by the anterior pituitary that stimulates the thyroid.

Cortisol

A hormone released by the adrenal glands that regulates stress response and metabolism.

LH

Luteinizing hormone released by the anterior pituitary involved in regulating reproductive functions.

FSH

Follicle-stimulating hormone released by the anterior pituitary involved in gamete production.

Thyroid Hormones

Hormones (T3 and T4) secreted by the thyroid gland that regulate metabolism.

ACTH

Adrenocorticotropic hormone released by the anterior pituitary that stimulates cortisol release.

Oxytocin

Hormone released during childbirth that increases uterine contractions and amplifies its own release.

Cushing’s Disease

A condition characterized by excessive cortisol production often leading to immune suppression.

Thyroid Hormone Production

Regulated through feedback mechanisms including TRH and TSH.

Thymus Gland

An organ that can be suppressed by prolonged cortisol excess, leading to immune deficiency.

Molecular Mechanism of Symptoms

Biological process explaining symptoms like weight loss, hyperthermia, and increased heart rate in endocrine disorders.

Hormone Replacement Therapy

Treatment involving the administration of hormones to compensate for insufficient levels, as seen in Addison's disease.

Heat Intolerance

A condition likely caused by hyperthyroidism, leading to an increased metabolic rate.

Exophthalmos

Bulging eyes often seen as a symptom of Graves' disease due to excess thyroid hormone.

Thyroidectomy

Surgical removal of the thyroid gland, may be indicated in severe hyperthyroidism.

Metabolic Rate

The rate at which the body uses energy, which can be influenced by thyroid hormones.

Physiological Responses

Reactions of the body that can indicate hormonal changes, like weight gain/loss or changes in activity levels.

Hypothalamic Regulation

The process by which the hypothalamus controls hormone release, linking the endocrine and nervous systems.

Gonadal Hormones

Hormones produced by the gonads (testosterone and estrogens) that affect reproductive functions.

Control Conditions

Experimental setups in research that help establish relationships between hormones and observed physiological effects.

Physiological Effects of Castration

Changes observed in organ size and hormone production following the removal of gonads.

Hyperpigmentation

Darkening of the skin often associated with adrenal insufficiency in Addison's disease.

Insulin

A hormone produced by the pancreas that regulates blood glucose levels.

Glucagon

A hormone produced by the pancreas that increases blood glucose levels.

Thyroid Stimulation

The process by which the TSH stimulates the thyroid to produce thyroid hormones.

Hormonal Feedback Loops

Regulatory processes involving negative and positive feedback that maintain hormone balance in the body.

Secondary Sexual Characteristics

Features that develop during puberty influenced by sex hormones from gonads.

Insufficient Hormone Production

Condition when a gland does not secrete adequate hormones, leading to various health issues.