Comprehensive Notes on Hormones and Glands

Hormones and Their Functions

Releasing Hormones

• Control the release of anterior pituitary hormones.

Posterior Pituitary Hormones

ADH (Antidiuretic Hormone)

• Promotes water reabsorption in kidney tubules.
• At high concentrations, stimulates constriction of blood vessels.

Oxytocin

• Causes uterine muscle contraction.
• Causes milk ejection from mammary glands.

Anterior Pituitary Hormones

GH (Growth Hormone)

• Promotes growth of all body tissues.

TSH (Thyroid Stimulating Hormone)

• Stimulates thyroid gland to produce thyroid hormone.

ACTH (Adrenocorticotropic Hormone)

• Stimulates growth and hormonal activity of the adrenal cortex.
• Important in the body's response to stress.

PRL (Prolactin)

• Stimulates milk production by mammary glands.

FSH (Follicle Stimulating Hormone)

• Stimulates growth and hormonal activity of ovarian follicles in females.
• Stimulates growth of testes and promotes sperm cell development in males.

LH (Luteinizing Hormone)

• Initiates ovulation, corpus luteum formation, and progesterone production in females.
• Stimulates testosterone secretion in males.

Other Hormones

PTH (Parathyroid Hormone)

• Regulates exchange of calcium between blood and bones.
• Increases the calcium level in blood.

Cortisol

• Increases blood glucose concentration in response to stress.

Aldosterone

• Promotes salt (and thus water) retention and potassium excretion.

Insulin

• Reduces blood glucose concentrations by promoting glucose uptake into cells and glucose storage.
• Promotes fat and protein synthesis.

Glucagon

• Stimulates the liver to release glucose, thereby increasing blood glucose levels.

Testosterone

• Stimulates growth of primary sexual organs (uterus and tubes) and development of secondary sexual organs, such as breasts in females.

• Stimulates development of ovarian follicles.

• Stimulates growth and development of sexual organs (testes and penis) in males.

• Development of secondary sexual characteristics such as hair growth on the body and face and deepening of voice in males.

• Stimulates sperm cell maturation.

Progesterone

• Stimulates development of mammary glands' secretory tissue.
• Prepares uterine lining for implantation of fertilized ovum and aids in maintaining pregnancy.

Estrogen

• Contribute to some secondary sex characteristics in women.

Thyroxine (T4) and Triiodothyronine (T3)

• Increase metabolic rate, influencing both physical and mental activities.
• Required for normal growth.

Epinephrine

• Increases blood pressure and heart rate.
• Activates cells influenced by the sympathetic nervous system.

Melatonin

• Regulates mood, sexual development and daily cycles in response to the amount of light in the environment.

Hormone-Secreting Glands

• Hypothalamus
• Anterior Pituitary
• Posterior Pituitary
• Thyroid
• Parathyroid
• Adrenal Medulla
• Adrenal Cortex
• Pancreatic Islets
• Testes
• Ovaries
• Pineal