New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here


by: Marjolaine Smitham


Marjolaine Smitham
GPA 3.68

C. Williams

Almost Ready


These notes were just uploaded, and will be ready to view shortly.

Purchase these notes here, or revisit this page.

Either way, we'll remind you when they're ready :)

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

C. Williams
Class Notes
25 ?




Popular in Course

Popular in Animal Science

This 36 page Class Notes was uploaded by Marjolaine Smitham on Tuesday October 13, 2015. The Class Notes belongs to ANSC 4043 at Louisiana State University taught by C. Williams in Fall. Since its upload, it has received 35 views. For similar materials see /class/222512/ansc-4043-louisiana-state-university in Animal Science at Louisiana State University.

Similar to ANSC 4043 at LSU

Popular in Animal Science




Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 10/13/15
Chapter 20 Endocrine Role of the Pineal Gland CHAPTER 8 Melamnin and the Pineal and Retina 148 Figure Ll Th gure iIlusLmlcs pincal gland regulation according m Descartes The scvenluanh cenlury en gmving shows the rcgulnlion ul llw pineal glnnzl named for its pine cone shape localcd mum ccnxmlly llmn shown by lighl perceive wiLh Lhc eyes Rnproduccd with pcmmion Crapo Ll Hnrmnncs 39l39huMcssengcrsol Life W PL Freeman C0 New York 1935 11 80 Pineal gland the seat of the soul Pineal Gland Also called epiphysis cerebri pinecone shaped single organ located in the head deeply recessed under the cerebral hemisphere parenchyrnal cells pinealocytes quotMquot m Pmluimlobn Pnlnymms G quot211 Org m locrine Role of the Pineal Gland Falx Cerebri Cingulate Gyrus of Cerebral Hemisphere Splenium of Corpus Cailosum Cerebeilum Tenorium Cerebelli Great Cerebral I vein Epiphysis Fornix Midbrain Chorid Plexus Pineal Recess Habenular Commissure Posterior Commissure Subcommissural Organ Ventricle Figure 201 The human pineal gland epiphysis and its anatomical relation to the diencephalic roof From Wurtman Axelro d and Kelly 1966 Evidence for a nonretinal pathway of light in the pineal gland of newborn rats Proc Na AcadS39c1 USA 56515 20 with permission Figure 33 The gure shows a plmmgmph af a sauna through me parls of the brain and the pineal of Lhc house sparrow Passer Muslim P pineal c cerebellum CH cerebral hemisphere The bug slalk of ma gland ands 31 me churoid plexus Photograph by me audmr Pineal Gland Hormone produced melatonin antigonadotropic in some animals involved in control of reproductive processes of certain mammals possibly humans Melatonin Synthesis See gure 204 Precursor tryptophan amino acid series of intermediates several enzymes N acetyltransferase important step probably rate limiting step HIOMT also important NH2 H l c c cooH xryplophan melatonin 1 H H N lryplaphan hydraxyrasa 6hydroxymelelonin NH2 Ho H l C O COOH 5hydmxyxryplophan l H H N H sOcom ugates 5hydroxylryplophan decarboxylase NHz melatonin Ho l S C H sevotanin H H N H NacexylNkzrmylSmethoxykynurenine sermonh Nacslyllranslerase 3 C CH 1 u 3 H H0 cc o N39ace ylsemmnin N acetyl 5 methoxykynuvenme l I H H N H hydoxyindoleOmelhylranslerase H N CHa H cHso c c o melalunin H H N H Flgure 86 The pathway for melalunin synthesis is on the lst On he right are the convusion palhwnys for l lonin to conjugnms in the liver and m uxeninc in the brain Modi ad with pennissiun Mmim CR Endmine thsinlnzv New York Oxfmd Universilv Press 1985 n 853 Melatonin Synthesized in the dark at night N acetyl transferase activity increases in dark Rate limitng step Fig 205 serotonin to melatonin in chicks 6 fold increase in serotonin 21 fold increase in N acetyltransferase 13 fold increase in HIOMT 10 fold increase in melatonin 460 Chapter 20 Endocrine Role of the Pineal Gland l 30 E 20 Serotonin g I I E 10 6 Fotd AcetyICoenzyme A Coenzyme A NeAcetyltransferase gt Actwny nmglandhr NAcetylserotonin 3D 20 1O 21Fold 0 M 539 E 300 SAdenoeyl HydroxyindoIeO 200 Methionine Methyltransferase a g 100 M W c o lt E 13Fold SAdenosyl C 0 Homocysteine 30 E 20 m Melatonin gt g 10 10 Fold C 0 4 N 0 i 24hour LightDarkness Cycle LD 1212 Figure 205 Pathway for serotonin conversion to melatonin in the pineal gland Daily measurements over a Z4 hour period of serotonin content N acetyltransferase activity NAT hydroxyindole O methyltransferase activity HIOMT and melatonin content in chick pineals were made The ar at the top of the graph represents the 24hour lighting regimen in which the birds were held LD 12 12 hours of light in alternation with 12 hours of dark The daily change in melatonin is believed to be a consequence of the daily change in NAT The numbers x fold on the graph are the ratio of peak to nadir values From Binkley S A 1979 Pineal rhythms in vivo and in vitro Comp Biochem Physio 64A201 6 with permission CHAPTER 8 Melatonin and the Pineal and Relina 155 30 rig91am seinlonin E gt E C E g 01 M r Nacelynmiislmase acliwly J g 1110er mm 300 nmmsi glandhr 5 iiggianu I W meialor m 12 hours dark Figure 88 Th graphs shuw the rhythms in our pinml biochemical pmamclcrs in chicks kcpl in an 11312112 lightdan cycle The 1 101 C m 1 peak in melatonin is believed to bi dcrivcd 1mm 11m 21fold rhyihm in pineal Nacclylunnsferase souvin which produces 11 midLluxk 510111 decrease in ihe subsumc scrolunin Hylexyindoic Ovnlcmyluansfcmsc acliviy 11101111 cxhihilnd a 13fold changm Th heighl or he rccnmglcs on Lhe Hm an 31 in die unils inscribed 39 11w rectangles The chick pineal Nacclyllransfcrasc lhthm was rm published in Binklcy 5 MncBride chin D Ralph Pineal enzymes Regulaliun ofnvian molar lonin syn tsis Scienca 131 273475 1973 me scmanin dam are 1mm munch M in cy rhthms of scrolcnin and Nacelylurmsfcmse in chicks Comp Dischem Physiol 63C 305407 19 CHAPTER 8 I Melatonin and he Pineal and Retina 154 5000 d fkviime 4000 u n F g 3000 m in E 2 m c g 2000 gt K llglvh all lighis on man n 0 4 q 12 m 16 i7 m 20 22 24 um Flgure 87 A dnily cycle is found in sparrow pineal Nnncelyiuansfcmsu Icivily In LD1212 ligmsaff rmm noon in midnighl 1hr enzyme nclivuy is low during Lhc as when ii i Iiqu and high during zhc nigh whcn h is m 39mc wprcsenls lime orday Easicm Dayli h Savings Time 1 nuon 24 2400 midnight N ncuiylimnsfumxc univin is given in pmolcs of pmduci formed per pineal gland par mun Ems rcpmscni average and le arm was am one standard mm or hm mchn Dam colicclcd by me author and Si Klein v CSF Melatonin pgml a o 8 0 Lighting 0 Schedule Chap 20 End 600 1000 0500 1000 0000 1000 0000 1000 0000 1000 0600 100 Clock Time his ocrine Rule of the Pineal Gland Subiemi Subject Ti E m i Subjecis E 2 E 5 Subject 4 c 2 E m 2 b39 t5 5 lee Flgure 208 Diurnal plasma mela tonin levels in humans Note he nocturnal elevation during fuur con secutive cycles in ve adult male M s E subjects From u han Meyer and aa 39 Reiier Journal afCinical Endacrinoi u y and Metabulism vol 42 pp 752 764 1376 J B Lippincott Publishing Company used by permission Figure 209 Diurnal pattern of CSF melatonin in the rhesus monkey An individual animal was studied for 6 consecutive Endocrinology 1042957301 1979 1979 American Roent gen Ray Society Williams 81 Wilkins Company Control of melatonin synthesis CNS involved Light information is conveyed to suprachiasmatic nuclei SCN of brain neuronal circuits from SCN convey information to spinal cord and then to superior cervical ganglia Norepinephrine released from superior cervical postganglionic neurons icrine Role of the Pineal Gland Pinealocyte Tr39yp topria 39 Norepinephrine I r 5Hydroxytryptopha t Superior Amino Suprachiasmatic Cervical iyhglli ACIdS seromnin Nucleus Ganglion E 397 Adenylate Protein gtNAT Cyclase Synthesis Upper Thoracrc ATP NAcetyl serotonin Cord HlOMT BAdrenergic L Receptor Melatonin r 39 39 39 V intracellular quot ActionS39 7 Intermediolateral Cell Column Figure 207 CNS pathway and mechanisms controlling pineal indole metabolism in mammals From Karasak and Reiter Morpho functional aspects of the mammalian pineal gland Microscopy Res Tech 21136 57 1992 John Wiley 8 Sons Inc Used by permission of WileyLiss Inc a subsidiary of JohnWiley 8 Sons Inc Melatonin Skin color Change seasonal reproduction regulation of Circadian rhythms photoreception Skin color Role of pineal gland is straightforward pineal glands fed to tadpoles color lightened amphibians dark time pallor lack of color lizards in constant dark higher vertebrates hamsters weasels delay in change from White Winter coat delayed by melatonin implantation MSH inhibition by melatonin Reproduction seasonal breeding animals Animals cycle between reproductively active breeding and inactive non breeding on an annual or seasonal basis rationale ensures that offspring are born when conditions are optimal for growth Melatonin increases during short days Seasonal breeding animals Hamsters long days of spring stimulate growth and function of gonads duplicated in lab hamsters placed in short days lt12 hrs light or blinded in constant dark regression of testes and ovaries removal of pineal gland abolishes this inhibition of reproduction Reproduction cont Hamster project support for idea that pineal gland was source of antigonadotropic hormone short days Nacetyl serotonin synthesized by Nacetyl transferase throughout the long night high HIOMT activity convert it to melatonin so melatonin is present for long duration Chap 20 Endocrine Role of the Pineal Gland Pineal and Annual Reprodumive Cycle in a Long Day Breeder inhibition Sexually Quiescent Restoration Sexually Active Phase 39 Phase Phase Phase Refractory Periodinterrupted by Ught Dark Requires intact Light Dependent Pineal Gland Breeding Parlod Ea Delivery of Young Q N Q at P 0 E a to o a ms 1 t Pineal Activity 5 g 1 l Pineal Activity a 72 2 T Sensitivity of 5 Q8 2 l Sensitivity of g a Neuroenoocrine g g Neuroendocn39ne Axis 3 L 3 Axis 15 57 3 Both 1 and 2 7 3 Both 1 and 2 Q9 gt 3i Short Daysquot Long Days l l l i l I I I l A S 0 N D J F M A M J J A Autumnal Winter Vernal Summer Equinox Solstice Equinox Solstice Month of Year Figure 203 The role of the pineal in the annual reproduction cycle of a iongday breeder the hamster From Reiter with permission Progress in Reproductive Biology 4169 90 1978 CHAPTER 8 Melatonin and the Pineal and Retina 159 nhmosenstlwe plmlarelmctory termtrtahon Ol veltactcvlnsss harm smvtty lo mgtt lenghtemng spoltlamzuus csucmm tecrudescence qunau slze tmsnculm regtessvon m response to long nig lusles Ingresst Sap on Nov Dec Jan Feb Mar Am May Jun Jul Aug Sep long nights shovl mghts Flgure tut Th xtnnuttl pmgtcss or m tepmduclivt swam in a seasonal breeding animal such as m hamster is shown Cantu silt is reprcsunltd as on the left descriptions tcl39cr lo he leslis m the right The tastes get smaller regress us the days sllo en 39ntc nnimnls are rcpraductivcly quiescent As the tys lengthch the lute enlarge and become functional mmdescc through the brccdmg scnson In the absence of long days the lcslns will slilI begin to cnlrugc which is called sponlatmnus recrudescence However umly decline in testis size cannot be provoked by s on days until lhe refractory pcriod is complulcd ter Stetson 39tmyrc hysiology of the pine and its mrmonc melatonin in annual reproduction in rodcnls lu Reitcr R uditor The Pineal Glandr New York Ruvun Press 1984 Melatonin Believed to inhibit reproductive system by inhibiting prolactin which normally stimulates reproduction melatonin may act Via the hypothalamus to stimulate dopamine PIF intriguing process evolution has produced an exquisite system of birth control CHAPTER 8 I Melzlunin and III Pineal Ind Retina 15H ligm L lives I from me opilc news and is a allcl mnnaailnn iailnuhypoihalamic new ram Tile aunracnlnsmalic nuclei iscN is in mo ii liinlamua and is ma pmoania sno oi mo ascillaioi Acllnu as pacemaker ior aicamnn myilims in mnmmals v nerve vans Tim superior cervical ganglia ooniain nerve cell ooolas whose processes axons lomunnio in ma ulnaal giann whom may misuse nomplnlphllna NE a nauvollanami em which slimulalas plnoni uii Nacslyilianslarasa acllviiy me quotam in me oineai gland Nnceiyilmnslerase ecllviiy has a clicadlsn in in peak in line dark which ls ln lulu yin responsible In me daily myihm n noun synlhexis and ma durallcil oi melaiunln produnliun melalanin ights may acl via lne hynukhalamus Io oiiniuinia Dummy dopamine which acliog as FIF on ma pliolinry gland Inhlblla prolaciln snoner dumilon oi meiolonln lam Dmlaclln sllmulalml gonad lecrudesence The seasonal alloci oi pinnaiaclomy nu ma ieploducllve yysiorn ls wobably quotgullin ma mum oi proiacun Pinealocio ma raillava Ihe lnnlbllson oi shall days long nigms 50 quotall mulscun WM Sllmulalos gonad gmwm Flgure 310 no pineal gllnd is onlmllad by envimnmenul light Ind in mm mgulnlcs eucnl branding Circadian rhythms Variation during day blood pressure pulse temperature Lightdark photoreception Pineal gland synthesizes melatonin in response to photic information received melatonin produced in retina of many animals may regulate cyclic metabolism of photoreceptor cells may play a role in retinal light sensitivity and visual acuity in some vertebrates Melatonin in Humans Antiaging hormone Dracula of the endocrine system as humans age pineal failure decreased melatoninz5HT ratio Cancer blind women increased melatonin decreased risk melatonin reduces gonadotropins delays puberty Less exposure to estrogens Low melatonin earlier beginning of cycle longer exposure to estrogens Melatonin Supplements I nd that 1 t0 3 mg of melatonin a half hour before bedtime Ema helps me quickly fall asleep even when I m traveling Lee Swanson President Swanson Health Products Melatonin Supplements 0 Melatonin readily available in drug stores and health food stores and it has become quite popular Ingesting even modest doses of melatonin raises the melatonin level in the blood to as much as 100 times greater than normal These levels appear to promote going to sleep and thus help insomnia to hasten recovery from jet lag not to have dangerous side effects Also touted as an antiaging hormone Other claims SAD endocrine disorders Why is melatonin used as a dietary supplement Treating seasonal affective disorder SAD Helping regulate sleep for people Who work evenings or nights Preventing or reducing problems with sleeping or confusion after surgery Reducing the side effects of some antipsychotic medications used to treat schizophrenia Reducing or preventing chronic cluster headaches Osteoporosis Melatonin has been shown to stimulate cells called osteoblasts that promote bone growth Since melatonin levels may be lower in some older individuals such as postmenopausal women current studies are investigating whether decreased melatonin levels contribute to the development of osteoporosis and whether treatment with melatonin can help prevent this condition httpwwwummedualtmedarticlesmelatoninOOO3 l 5 htm Depression A recent study of postmenopausal women found that melatonin alleviated both depression and anxiety Other studies show that people who suffer from major depression or panic disorder have low levels of melatonin Healthy individuals with mild episodic depression and patients who have Seasonal Affective Disorder SAD a mild depression that correlates with fall and winter periods of lightphase shortening also have lower than normal melatonin levels Experimental studies show that melatonin causes a surge in the chemical serotonin which helps alleviate symptoms of depressive illness including major and mild depression and SAD Melatonin should be used with caution in people with depression and should be appropriately timed with light therapy and sleepphase changes Disruption of normal circadian rhythm by poorly timed melatonin administration may worsen depression Pediatric Less than 03 mgday Although studies in children suggest that doses of 110 mg melatonin have little to no side effects there is not enough information to clearly say that doses greater than 03 mg per day are safe in children under age 15 In fact doses between 1 to 5 mg may cause seizures in this age group Adult Insomnia 3 mg one hour before bedtime is usually effective although doses as low as 01 to 03 mg may improve sleep for some people If 3 mg per night is not effective after 3 days try 5 to 6 mg one hour before bedtime An effective dose should produce restful sleep with no daytime irritability or fatigue Jet lag 05 to 5 mg of melatonin one hour prior to bedtime at final destination has been successful in several studies Another approach that has been used clinically is 1 to 5 mg 1 hour before bedtime for 2 days prior to departure and for 2 to 3 days upon arrival at final destination Sarcoidosis 20 mg per day for 4 to 12 months Take melatonin to treat this speci c health condition only under medical supervision Do not take melatonin supplements longterm without consulting your doctor Depression 0125 mg twice in the late afternoon each dose 4 hours apart for example 4 PM and 8 PM People with depression tend to be particularly sensitive to the effects of melatonin meaning that a very low dose is generally enough to achieve the desired outcomes Melatonin Supplements Careful not to overdo these as with any Not FDA approved purity safety and effectiveness can39t be assured Trouble sleeping see your doctor SONATA Too much may numb the SCN Unknown repro effects in humans Lipophilic easy access to all cells Long term use Melatonin Receptor Membrane receptor Member of G protein linked receptor superfamily Evidence for intracellular actions with CaM


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Bentley McCaw University of Florida

"I was shooting for a perfect 4.0 GPA this semester. Having StudySoup as a study aid was critical to helping me achieve my goal...and I nailed it!"

Jennifer McGill UCSF Med School

"Selling my MCAT study guides and notes has been a great source of side revenue while I'm in school. Some months I'm making over $500! Plus, it makes me happy knowing that I'm helping future med students with their MCAT."

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.