Regulation of: Metabolism Water and Electrolyte balance Red Blood Cell Production Control of: Reproduction Smooth, sequential growth and development
Oxytocin: Uterine contraction Milk ejection from Mammary gland Release stimulated by delivery and infant suckling Vasopressin (Antidiuretic Hormone): Enhances water retention by kidneys (hence antidiuretic) Major regulation of urinary water loss and overall water balance Causes contraction of arteriolar smooth muscle (vessel pressor effect) Little normal control of blood pressure Released via hypothalmic osmoreceptors when an increase in osmolarity is dected (ie, a decrease in plasma levels)
Growth Hormone (GH) responsible for regulating growth and development important in regulating metabolism (increases use of stored fats, decreases glucose utilization) Thyroid-Stimulating Hormone (TSH) Increases metabolic rate acting on thyroid gland Adrenocorticotropic Hormone (ACTH) Increases cortisol secretion by adrenal cortex Promotes growth of adrenal cortex Follicle-Stimulating Hormone (FSH) Males: required for sperm production Females: stimulates growth and devlopment of ovarian follicles Luteinizing Hormone (LH) Males:responsible for secretion of testosterone by testes Females: responsible for ovulation, secretion of estrogen and progesterone by ovaries Prolactin (PRL) Females: Enhances breast development and milk production
Thyroid Hormone: Effects virtually ever body tissue Increases the body’s overall basal metabolic rate or “idling speed” Increases Oxygen consumption and energy expenditure Slow action, long duration Increases heat production via increased metabolic rate (Calorigenic Effect) Sympathomimetic Effects with increased thyroid stimulation increased production of catecholmine receptors
Cretinism Exhibits signs of dwarfism because skeleton fails to grow or mature Severe Mental retardation In adult onset, causes Myxedma S/S: facial swelling, bradycardia, decreased body temperature, weakness, leathergy Treatment aimed at thyroid replacement
Exophthalmos Grave’s Disease Increased metabolism, tachycardia , heat intolerance, increased sweating, weight loss despite good apetite, insomnia, nervousness Treatment: surgical removal of part of thyroid gland or radiation therapy to destroy part of thyroid
Parathyroid hormone: Increases Calcium concentration in plasma and, therefore, ECF. Complete lack of parathyroid hormone leads to death within several days, usually due to hypocalcemic spasm of respiratory muscles
Alpha cells: glucagon Opposes action of insulin Increases blood sugar levels by: decreasing glycogen synthesis increasing glycogen breakdown into glucose Beta cells: insulin Decreases blood sugar by: Promotes glucose transport into most cells by increasing the number of glucose-transporter proteins available on cell membrane. Brain doesn’t require insulin for transport Increases glucogenesis (creation of glucose) Increases glycogenolysis (breakdown of glycogen) Delta cells: somatostatin Inhibits production and release of both glucogon and insulin
Medulla Epinephrine and Norepinephrine Part of SNS, responsible for catecholmine release which prolongs fight or flite response Cortex: Glucocorticoids, mineralocorticoids Glucocorticoids: increase blood glucose levels prevent inflammation are released in response to stress