• neural has a rapid and precise response
• Hormonal is a for a response that requires duration

• long distance chemical mediator transported through the blood
• secreted by endocrine glands
• bind to target cell receptors

1. Direct communication - gap junctions
2. Paracrine - local hormones within tissue(NO Blood)
3. Endocrine - Hormonal messengers through blood (one tissue to another)
4. synaptic - neural communication through release of NT's

1. Exocrine - use ducts to send chemicals like gastric secretions and bile (nonhormonal)
2. Endocrine - secrete chemicals into the ECF to get picked up by lymphatic ducts or vascular rich surrounding tissue

Major Endocrine Glands?

Partly endocrine?

Major = pineal, pituitary, thyroid, parathyroid, pancreas, adrenal, ovary, testis

Partly = hypothalamus, liver, thymus, heart, kidney, stomach, duodenum

1. organic metabolism
2. water/salt balance
3. stress coping
4. smooth growith and control of development
5. Regulate RBC production
6. control digestion, circulation and absorption of nutrients

Tropic - regulates production of another hormone

Non-tropic - directly stimulate target cells to induce effects.

1. peptides and proteins
2. Amines
3. steroids

• specific chain of AA's (most common)
• Hydrophilic and lipophobic
• soluble in water not lipids

• Derived from Tyrosine from adrenal medulla (NE and E)
•  hydrophilic, lipophobic
• Exception - thyrocrine is lipid soluble and hydrophobic and transported via carrier proteins

• derived from cholesterol
• some from adrenal cortex (aldosterone, cortisol)
• others from sex organs (testosterone, estrogen, progesterone)
• hydrophobic and lipophilic

1. change membrane permeability of ions
2. cause protein synthesis
3. activate/deactivate enzymes
4. induce secretion
5. stimulate mitosis

1. bind to target cell receptor
2. G protein is activated
3.  activates effector (adenylate cyclase) to produce enzyme
4. which is 2nd messenger cAMP
5. cAMP then activates protein kinase
6. activated kinase can activate enzymes, secrete hormones, stimulate mitosis, etc.

• hundreds of final product molecules can be generated from 1 hormone

• phosphodiesterase, an intracellular enzyme, can break down cAMP to deactivate kinase and stop response

1. hormones diffuse through membrane and bind with inracellular receptors
2. hormone-receptor complex reaches chromatin in nucleus and prompts transcription of mRNA
3. translation by cytoplasmic ribosomes produce end products
4. could be enzymes, proteins for export, etc.

1. number of receptors
2. hormone concentration
3. binding affinity

increase in hormone will... probability of binding?

increase in # of receptors will...probability of binding?

decrease attraction between hormone and receptor will.... prob. of binding?

increase

increase

decrease

receptors

amount of endocrine cells

• Anterior pituitary - NO neural tissue, ENDOCrine Tissue that produces 6 hormones.  release is controlled via hypothalamus which releases hormones to allow or inhibit hormone secretion
• Posterior pituitary -  NEUral Tissue, stimulated by hypothalamus to secrete 2 hormones; oxycotin, and ADH.

• zona glomerulosa = mineralocorticoids - mineral, water, and salt balance
• zona fasciculata = glucocorticoids - metabolism
• zona reticularis = gonadocorticoids - sex hormones

chromaffin cells that secrete catecholeamines into blood.

80% E and 20% NE

mineralocorticoids?

hyper or hyposecretion caused by?

water and salt balance

primarily Aldosterone

• hyper - caused by too much aldosterone production causes hypertension, edema, loss of K+
• hypo - addison's disease

glucocorticoids?

hyper and hypo?

regulate metabolism

blood sugar levels and BV

• primary hormone is cortisol
•  hyper - inhibits inflammtion and depresses cartilage and bone formation
• hypo - addison's disease

gametogenesis?

spermatogenesis?

oogenesis?

• requires both mitotic and meiotic divisions of germ cells
• S - spermatogonium (2n) to spermatozoa (1n)
• O - oogonium (2n) to ovum (n)

what is the sex determining gene? which sex does it create?

which chromosome?

W = mesonephric M = paramesonephric

wolfian duct belongs to males and mullerian to females

• SRY gene encodes for Testis determining Factor(TDF)
• leydig and sertoli cells act as receptors for human chrionic gonadotropin (HCG)

• leydig cells produce testosterone
• sertoli cells produce mullerian inhibiting hormone
• Therefore the wolfian duct develops into the vas deferens and the mullerian duct degenerates

• No SRY gene so TDF so no testosterone of MIH
• cortex develops into ovary = estrogen
• mullerian duct develops into uterine tube (fallopian)
• wolfian duct degenerates

what induces the formation of the male reproductive tract?

what hormone doesnt induce the formation of the reproductive tract?

androgens and MIH

estrogen

formation and differentiation of sex hormones?

what enzyme creates estradiol? dihydrotest?

cholesterol to progesterone to testosterone

then

dihydrotestosterone or estradiol

aromatase and reductase

• MAles - T can enter and be transformed into Estrogen which then goes to the hypothalamus and releases other hormones producing a Tonic pattern of neural signaling
• Females - E2 can't enter the POA and therefore no estrogen can affect the hypothalamus so it produces a pulsatory pattern of neural signaling

1. nourish sperm cells
2. phagocytize dead cells
3. secrete inhibin
4. use ABP (androgen binding protein)
5. secrete luminal fluid

negative feedback mechanism

Role of T?

role of sertoli cells?

Inhibin?

ABP?

1. T produced by leydig cells - stimulates sertoli cells to increase spermatogenesis.  inhibits release of LH from pituitary and gonadotropin releasing hormone from hypothal.
2. SC - produces inhibin and stimulates spermatogenesis
3. I - inhibits FSH secretion by pituitary
4. ABP - concentrates T for sertoli cells

• enhances synthesis of proteins in target cells
• development and maintenance of male reproductive organs
• skin, hair, libido

5% sperm

95% fluids

what triggers erection?

summary of chemical events?

spinally mediated through thoughts and mechanoreceptors in tip of penis

• increase in NO triggers cGMP which maintains vasodilation
• phosphodiesterase breaks down cGMP which stops erection

4-6 days

low pH of vagina, phagocytosis by uterus

24 hours

in the distal 1/3 of the oviduct

• infundibulum - closest to ovary, have fimbriae
• ampulla - site of fertilization
• isthmus - connects to uterus, moves egg down by peristalsis

• granulosa - secrete inhibin and estrogen
• Theca - secrete androgens

• FSH initiates Cholesterol conversion to testosterone in theca cells
• T transferred to to granulosa cells where it is converted into Estradiol by aromatase (supplied by LH).
• LH also produces inhibin which stops production of FSH and increases LH
• follicle continues growth

early follicular phase?

mid follicular phase?

late follicular phase?

• LH and FSH start to increase, group of follicles begin growth
• dominant follicle selected, increase of estrogen and inhbin causes decrease of FSH(less T made)
• high E2 levels induce pituitary to produce a LH surge.  increase GnRH and LH while FSH is still inhibited by inhibin

• rupture of graafian follicle
• ovulation
• theca and granulosa cells transformed into corpus luteum

• progesterone and small amounts of estrogen
• causes no new follicles to develop

• estrogen alone makes mucus plug thin and watery to allow sperm entrance
• progesterone makes mucus plug thick so no bacteria can get into the uterus to affect reproduction

• the corpus luteum will remain active for around 3 months continuing to produce estrogen and progesterone until placenta can take over to produce lots of hormones
• continued by HnCG

• hCG - becuase it begins secretion about 1-10 days after fertilization and continues for about 3 months.

• follicular - produce thyroglobulin that combines with iodine to produce 4 different throid hormones (T1, T2, T3, T4)
• parafollicular - produces calcitonin

• what does TH do?

concerned with:

-glucose oxidation

-increasing metabolic rate

-heat production

for:

- developing skeletal and nervous systems, BP, Reproduction, tissue growth

1. thyroglobulin enters lumen of follicle
2. iodide is converted into iodine in the follicle cells and secreted into lumen
3. iodine attaches to thyroglobulin to form T1 or T2.
4. then tyrosines are linked together to form T3 and T4.
5. enter lysozomes and are cleaved from thyroglobulin colloid and hormones diffuse into bloodstream.

• bind to TBG (thyroglobulin binding protein) produced by liver
• T3 is 10 ten times more active than T4
• peripheral tissue cells regulate conversion from T4 to T3

• parafollicular cells
• lowers blood Ca levels - important in bone growth
• antagonist to Parathyroid hormone

• reduces osteoclast activity (which degrades bone to increase Ca)
• increases reabsorption of Ca into bone matrix
• regulated by Ca ion concentration in blood, neg. feedback mech.

• chief cells in parathyroid gland
• regulates [Ca] in blood
• stimulates osteoclast activity
• increase Ca reabsorption by kidneys and intestinal mucosa
• PTH inhibited by high levels of Ca in blood

calcitonin ... importance in adults?

PTH ... importance in adults

loses

gains

Pancreas acinar cells secrete?

2 islet cells? secrete what?

which are endo or exorine

• digestive enzymes (exocrine)
• endocrine below>>
• alpha - secrete glucagon
• beta - secrete insulin

purpose of glucagon: it promotes?

glycogenolysis?

glycogenesis?

• production of glucose in liver
• - conversion of glycogen to glucose
• - formation of glucose from noncarbohydrates and lactic acid

• lowers blood glucose levels by enhancing transport of glucose into cells

• oxidation of glucose for ATP production
• transforms glucose to glycogen
• converts glucose to fat

• hyper - pancreas releases insulin which stimulates the polymerization of glucose to glycogen which lowers the blood glucose level
• hypo - pancreas releases glucagon which causes the break down of glycogen to glucose increasing the blood glucose levels

• short - increased BP/HR, dilation of bronchioles, glycogen to glucose, ^ metabolic rate ( release NE and E)
• long term - retention of water and salt, increased glucose, increased BV/BP, suppression of immune system (release Glucocorticoids, mineralocorticoids