Endocrine System Hormones: Functions, Glands, and Target Tissues

ADH (antidiuretic hormone) - Endocrine Gland

Posterior pituitary

Oxytocin

Endocrine gland: Posterior pituitary

Target tissue: Uterus; Mammary gland

Function: Contracts uterus; milk let-down reflex

Epinephrine and norepinephrine (catecholamines)

Endocrine gland: Adrenal medulla

Target tissue: Nearly every cell in the body

Function: Increase HR & contraction force; dilate bronchioles; constrict blood vessels to the digestive/urinary organs and skin; raise metabolic rate; dilate pupils

Growth hormone (GH)

Endocrine gland: Anterior pituitary

Target tissue: Liver; Adipose tissue; Muscle; Bone & cartilage

Function: Stimulates gluconeogenesis, lipolysis, protein breakdown, IGF production for cell division/protein synthesis

TSH (thyroid-stimulating hormone)

Endocrine gland: Anterior pituitary

Target tissue: Thyroid gland

Function: Stimulates thyroid growth, development, and hormone synthesis

FSH (follicle-stimulating hormone)

Endocrine gland: Anterior pituitary

Target tissue: Male & female gonads

Function:

Males - promotes testosterone binding/concentration

Females - estrogen production & follicle maturation

LH (luteinizing hormone)

Endocrine gland: Anterior pituitary

Target tissue: Male & female gonads

Function:

-Males: Develop gonads, testosterone production

-Females: Develop gonads, produce estrogens and progesterone, ovulation

Prolactin

Endocrine gland: Anterior pituitary

Target tissue: Mammary gland

Function: Mammary gland development; milk production

ACTH (adrenocorticotropic hormone)

Endocrine gland: Anterior pituitary

Target tissue: Adrenal cortex

Function: Stimulates adrenal cortex growth & development; release of adrenal steroids & catecholamines

T3 (triiodothyronine) & T4 (thyroxine)

Endocrine gland: Thyroid gland

Target tissue: Nearly every cell in body

Function: Set basal metabolic rate, thermoregulation, growth & development, synergy with SNS

Calcitonin

Endocrine gland: Thyroid gland

Target tissue: Osteoclasts

Function: Inhibits osteoclast activity under certain conditions, which decreases blood calcium ion concentration

PTH (parathyroid hormone)

Endocrine gland: Parathyroid glands

Target tissue: Bone; Kidneys; Intestines

Function: Increase blood calcium concentration

Aldosterone (mineralocorticoids)

Endocrine gland: Adrenal cortex (zona glomerulosa)

Target tissue: Kidney tubules

Function: Retains sodium (directly) & water (indirectly), excretes potassium & hydrogen via urine, regulates BP

Cortisol (glucocorticoids)

Endocrine gland: Adrenal cortex (zona fasciculata)

Target tissue: Liver; Muscle; Adipose; WBCs

Function: Gluconeogenesis in liver, protein breakdown in muscle, lipolysis in adipose tissue, inhibits inflammatory response

Androgens

Endocrine gland: Adrenal cortex (zona reticularis)

Target tissue: Reproductive organs; Brain; Bone; Skeletal muscle

Function: Can convert to testosterone; likely responsible for development of female pubic hair & libido

Insulin

Endocrine gland: Pancreas

Target tissue: Liver; Cardiac muscle; Skeletal muscle; Brain

Function: Replenishes fuel sources depleted during fasting and helps maintain blood glucose through uptake of glucose, lipids, amino acids; glycogen synthesis in liver; fat synthesis from lipids/carbs; promotes satiety

Glucagon

Endocrine gland: Pancreas

Target tissue: Liver; Muscle; Adipose tissue

Function: Promotes reactions that increase glucose levels and other metabolic fuels (glycogenolysis, gluconeogenesis, formation of ketone bodies from fatty acids)

Testosterone

Endocrine gland: Testes

Target tissue: Testes; Bone; Muscle

Function: Anabolic (stimulates bone & muscle growth); Androgenic (develops male secondary sex characteristics like deeper voice, facial hair)

Estrogens

Endocrine gland: Ovaries

Target tissue: Female reproductive organs; Bone; Blood; Kidney; Adipose

Function: Female secondary sex traits (e.g., breasts); menstrual cycle regulation

Progesterone

Endocrine gland: Ovaries

Target tissue: Uterus; Smooth muscle

Function: Prepares body for pregnancy; supports fetal development; affects body temp, clotting, metabolism

Thymosin & thymopoietin

Endocrine gland: Thymus

Target tissue: T-lymphocytes

Function: Promote T-cell maturation; enhance immune function

Melatonin

Endocrine gland: Pineal gland

Target tissue: Sleep-regulating centers in reticular formation of brainstem

Function: Regulates sleep-wake cycle