| Endocrine gland/
source of hormone |
Hormone | Target organ or tissue | Major function is control of:- |
| Hypothalamus | Numerous releasing factors | Pituitary gland | Hormones release by pituitary |
| Anterior pituitary
(adenohypophysis) |
ACTH
(adrenocorticotrophic hormone) |
Adrenal cortex | Cortisol secretion |
| FSH
(follicle stimulating hormone) |
Ovaries / testes (tubules) | Ovarian follicle growth, oestrogen secretion / spermatogenesis | |
| LH
(luteinizing hormone) |
Ovaries / testes (Leydig cells) | Ovulation, luteinization of follicle / testosterone secretion | |
| GH
(growth hormone) |
All tissues | Growth; carbohydrate, protein and fat metabolism | |
| TSH
(thyroid stimulating hormone) |
Thyroid gland | Thyroxine secretion | |
| Prolactin | Mammary gland | Milk secretion (stimulates) | |
| Posterior pituitary
(neurohypophysis) |
ADH
(antidiuretic hormone) |
Kidney tubules
Smooth muscle in arterioles |
Water excretion
Blood pressure |
| Oxytocin | Uterine smooth muscle
Mammary gland |
Uterine contractions
Milk ‘let-down’ |
|
| Pineal gland | Melatonin | Various tissues | Circadian rhythm;
reproduction |
| Thyroid | Thyroxine (T4)
Triiodothyronine (T3) |
Most tissues | Metabolic rate;
growth and development |
| Calcitonin | Bone | Plasma calcium and phosphate (lowers) | |
| Parathyroids | PTH
(parathyroid hormone) |
Bone, kidneys, intestine | Plasma calcium and phosphate (elevates) |
| Thymus
(regresses in adulthood) |
Thymopoetin | T-lymphocyte cells in blood | Immune responses |
| Pancreas
(islet cells) |
Insulin
(from beta cells) |
Most tissues, notably muscle and liver | Glucose utilization;
blood glucose (lowers) |
| Glucagon
(from alpha cells) |
Primarily liver | Blood glucose (elevates) | |
| Intestinal mucosa | Gastrin | Stomach | Acid secretion |
| Secretin | Pancreas | Digestive secretions | |
| Cholecystokinin | Gallbladder | Release of bile | |
| Somatostatin | Intestine | Acid and intestinal secretions (inhibits) | |
| Adrenal medulla | Adrenaline
Noradrenaline |
All tissues | Metabolism; heart rate and output; response to stress and exercise |
| Adrenal cortex | Cortisol
Corticosterone |
All tissues | Metabolism; response to stress and exercise |
| Aldosterone | Primarily kidneys | Sodium, potassium and pH balance | |
| Kidneys | Renin (converted to Angiotensin-II) | Blood vessel smooth muscle
Adrenal cortex |
Blood pressure
Aldosterone secretion |
| Ovaries | Oestrogens | Reproductive organs | Reproductive development; also has effects on oestrus behaviour |
| Progesterone
(from corpus luteum) |
Uterus | Uterine condition | |
| Uterus | Prostaglandin
(PGF2?) |
Corpus luteum | Breakdown of corpus luteum
(luteolysis) |
| Placenta
(in pregnant mare) |
Progesterone and oestrogens | Corpus luteum | Maintenance of pregnancy |
| eCG (Equine chorionic gonadotrophin, PMSG) | Ovaries | Maintenance of pregnancy | |
| Relaxin | Uterus
Cervix, pelvic ligaments |
Uterine contraction (inhibits)
Increase in distensibility |
|
| Testes | Testosterone | Reproductive organs | Reproductive development; also has effects on behaviour |