《生理学教学课件：11-Endocrine2》由会员分享，可在线阅读，更多相关《生理学教学课件：11-Endocrine2（48页珍藏版）》请在金锄头文库上搜索。
1、The Pituitary GlandPituitary Gland nAdenohypophysis nNeurohypophysis. Pituitary GlandnCell Types nAdenohypophysis nSomatotropes: GHnMammotropes: PRLnThyrotropes:TSHnGonadotropes:FSH/LH nCorticotropes:ACTHnNeurohypophysisnNerve endings of the axons coming from the hypothalamic nuclei nNeuroglial cell
2、sAdenohypophysisnHormonesnGrowth hormone(GH)nProlactin(PRL)nThyroid-stimulating hormone(TSH)nAdrenocorticotropic hormone(ACTH)nFollicle-stimulating hormone(FSH)nLuteinizing hormone(LH) nMelanocyte-stimulating hormone(MSH)Adenohypophysis nFunctions of anterior pituitary HsGrowth Hormone nHuman growth
3、 hormone (hGH)nSomatotropinnProteinn191 amino acidsnAbout 22,000 (22k)Growth HormonenFunctionsnPromote tissue growth (bone, muscle,etc) nIndirect actionnSomatomedin nInsulin-like growth factor I (IGF-I) nInsulin-like growth factor II (IGF-II) Growth HormonenFunctionsnMetabolic Effectsnprotein deposi
4、tionnAA transport through the cell membranesn RNA translationnDNA transcriptionn Catabolism of protein and AAGrowth HormonenFunctionsnMetabolic EffectsnFat utilization for energyn“Ketogenic” effectGrowth HormonenFunctionsnMetabolic EffectsnCarbohydrate utilizationnGlucose uptakenGlucose production b
5、y the livernInsulin secretionGrowth HormonenRegulation of GH secretionnHypothalamusnGHRH: normalnGHIH: stressnSleep-wake cycle dependent rhythmGrowth HormonenSecretionnIn a pulsatile patternn1 4 hrsnNormal concentration in the plasmanAdult: 1.6 3ng/mlnChild or adolescent: 6ng/mlGrowth HormonenAbnorm
6、alities of GH secretionnDwarfismnGigantismGrowth HormonenAbnormalities of GH secretionnAcromegalyProlactinnProteinn207 AAnFunctionnMammary gland developmentn Milk productionnReproductionProlactinnRegulation:nProlactin-releasing factor(PRF)nProlactin-release inhibiting hormone (PIF)Melanocyte-stimula
7、ting hormone (MSH)nTypesn -, -and -MSHnPrimary effectnDisperse the melanin granules in melanophores nRegulationnMIFnMRF Posterior Pituitary Hormones nAntidiuretic hormone (ADH)nVasopressin(VP) nOxytocin (OXT) Antidiuretic hormone (ADH)-Vasopressin(VP)nSynthesisnSupraoptic nucleus nFunctionn water re
8、absorption by the kidneynVasoconstrictionAntidiuretic hormone (ADH)-Vasopressin(VP)nRegulationnOsmolarity of the blood nBlood volume Oxytocin nSynthesisnSupraoptic nucleusnParaventricular nucleusnSecretionnParturition, lactation and coitionOxytocinnFunctions n(+) milk ejectionn(+)uterine smooth musc
9、le contraction at birthnEstablishment of maternal behaviorOxytocinnControl of Oxytocin SecretionnPhysical stimulation of the nipplesnMilk ejection reflexnAcute stress n(-) OTX secretionnLevels of sex steroids The Thyroid GlandThe Thyroid HormonesnTypesThe Thyroid HormonesnConcentrationnThyroxine(T4)
10、: 93%nTriiodothyronine(T3): 7%nT4 T3nActivitynT3 = 5 T4The Thyroid HormonesnSynthesisnMaterialsnIodine (in the form of iodideI-)n50mg/yearnIodized table salt (1 sodium iodide/100,000 NaCl)nTyrosinenThyroglobulin (TG): 70 tyrosinesThe Thyroid HormonesnSynthesisnIodide trappingnIodide pumpnOxidation o
11、f the iodide ionnPeroxidase: I- I0 or I3-nIodination of tyrosinenPeroxidase nMIT and DITnFormation of T3 , T4The Thyroid HormonesnStoragenIn the folliclesnIn the form of TG (30 T4)nFor 2 3 monthsnReleasenTSHnProteinase(lysosome)The Thyroid HormonesnTransportnBound to plasma proteins: T4 (slow releas
12、e)nThyroxine-binding globulin(TBG): mainlynThyroxine-binding prealbuminnAlbuminnFree: T3nConcentration in plasmanT3: 1.2 3.4 nmol/LnT4: 85 142 nmol/LThe Thyroid HormonesnPhysiological functionsnEffect on growthnMainly in growing childrenn Skeletal growthnGrowth and development of brain (fetus and ba
13、by)nTadpole frognCretinism: deficiency of thyroid hormone during the period of fetal and early neonatal development The Thyroid HormonesnPhysiological functionsnEffects on metabolismnStimulation of carbohydrate metabolismn Uptake of glucosen Glycolysisn Gluconeogenesisn Rate absorption of Gn Insulin
14、 secretionnHyperthyroidism: G The Thyroid HormonesnPhysiological functionsnEffects on metabolismnStimulation of fat metabolismnLipid mobilization from the fat tissuenFree fatty acid concentration in the plasmanOxidation of free fatty acid The Thyroid HormonesnPhysiological functionsnEffects on metab
15、olismnProtein metabolismn Protein synthesis (normal)n Protein catabolism (hyperthyroidism)nHypothyroidism: myxedemaThe Thyroid HormonesnPhysiological functionsnEffects on metabolismn BMRn60 100%nHyperthyroidismnIntolerance to heatThe Thyroid HormonesnPhysiological functionsnEffects on the cardiovasc
16、ular systemn Blood flow and cardiac outputn HRnHeart strengthnNormal mean arterial pressureThe Thyroid HormonesnPhysiological functionsn RespirationnGastrointestinal motilitynExcitatory effects on the CNSThe Thyroid HormonesnPhysiological functionsnEffect on the function of the musclesnWeakened ( T3
17、,T4)nFine muscle tremor ( T3,T4)nSluggish( T3,T4)nEffect on sleepnConstant tiredness ( T3,T4)nDifficult to sleep ( T3,T4)The Thyroid HormonesnPhysiological functionsnEffect on other endocrine glandsnEffect on sexual functionThe Thyroid HormonesnMechanisms of actionnTranscription of large numbers of
18、genesnSynthesis of great numbers of proteinsThe Thyroid HormonesnRegulation of thyroid hormone secretionnHypothalamus-adenohypophysis-thyroid axisnAutoregulationThe Thyroid HormonesnRegulation of thyroid hormone secretionnHypothalamus-adenohypophysis-thyroid axisnTRHnTripeptiden TSH secretionnCold:
19、TRH releaseThe Thyroid HormonesnRegulation of thyroid hormone secretionnHypothalamus-adenohypophysis-thyroid axisnTSHnGlycoproteinn T3, T4 synthesis and releasen Size of the thyroid cellsncAMP mediated mechanismThe Thyroid HormonesnRegulation of thyroid hormone secretionnHypothalamus-adenohypophysis
20、-thyroid axisnFeedback effect of thyroid hormonenNegative feedbackThe Thyroid HormonesnRegulation of thyroid hormone secretionnAutoregulationnWolff-Charkoff effectSummarynTermsnGrowth hormonenThyroid Hormones nList the main physiological actions of thyroid hormonesGeneral questionnWhat are the endocrinologic causes of dwarfism and cretinism, and how does each lead to short stature? Intensive readingnTextbook of Medical Physiology (Guyton and Hall)nPage 848-852nPage 855nPage 861-865
