Endocrine Lesson 2 Monday, March 12 AIM: Where are hormones synthesized, and what is their effect? DO NOW: What is the difference between a steroid and a peptide hormone? HW: Memorize hormones/finish flash cards Multiple choice packet on hormones (Ch. 45)

Neurosecretory Cells Link the hypothalamus and the pituitary gland (the master gland)

Hypothalamus integrates endocrine and nervous function. Produces releasing hormones (or inhibitory hormones) that act on anterior pituitary (adenohypophysis) Produces hormones ADH and oxytocin that are stored in the posterior pituitary (neurohypophysis)

BE CAREFUL! The hypothalamus produces releasing hormones that stimulate the anterior pituitary to produce stimulating hormones. DO NOT CONFUSE OR EQUATE RELEASING HORMONES WITH STIMULATING HORMONES.

Posterior Pituitary (part of brain)  Neurohypophysis  stores and secretes hormones produced by the hypothalamus Fig. 45.6a

Anterior Pituitary

GH Growth hormone Gigantism Acromegaly Dwarfism Genetic engineering

Prolactin Peptide hormone Milk production

FSH, LH Follicle stimulating hormone Luteinizing hormone Have effects on testes (testosterone) and ovaries (estrogen and progesterone)

Female Hormones Estrogen and progesterone -- produced in the ovary Progesterone = the pregnancy hormone Estrogen  secondary sex characteristics Both are involved in the menstrual cycle

Male Hormones (Androgens) Testosterone Spermatogenesis Secondary sex characteristics

Thyroid Gland Regulates metabolism Homeostasis Secretes thyroxin (T3 and T4) Secretes calcitonin (lowers blood calcium – puts Ca back into bone) Needs I 2 Negative feedback Maturation Cretinism Goiter

Homeostasis and the Thyroid

Adrenal Glands Adrenal medulla – epinephrine -(fight or flight) – not under control of hypothalamus Vs. Adrenal cortex (mineralocorticoids and glucocorticoids) – under control of hypothalamus

Adrenal Adrenal Medulla Cortex Catecholamines –Adrenalin (epinephrine), norepinephrine Amines Fright, flight, fight hormones Target of ACTH from ant. pituitary Steroid hormones Glucocorticoids (cortisol) – increase blood sugar Mineralocorticoids (aldosterone) –increase reabsorption of sodium in CD and hence water— also increase bp via vasoconstriction

Pineal gland Circadian rhythm Has light sensitive cells Produces melatonin

Endorphins Natural opiates euphoria

Parathyroid Glands Secretes PTH which raises blood Ca +2 levels by breaking down bone Activates Vitamin D PTH and calcitonin are antagonistic hormones.