Presentation on theme: "Chapter 32 Disorders of Endocrine Function"— Presentation transcript:
1 Chapter 32 Disorders of Endocrine Function Essentials of PathophysiologyChapter 32 Disorders of Endocrine Function
2 Pre lecture quiz true/false Hypopituitarism is characterized by a decreased secretion of pituitary hormones.Hypothyroidism is evidenced by an increased metabolic rate, restlessness, irritability, tachycardia, diarrhea, and heat intolerance.Primary adrenal insufficiency, or Addison disease, is caused by destruction of the adrenal gland.Moon facies, buffalo hump, obesity, amenorrhea, and increased facial hair are manifestations of Cushing syndrome.Addison disease is a temporary condition.
3 Pre lecture quiz Acromegaly Cushing Graves growth puberty In children, _____________ hormone deficiency interferes with linear bone growth, resulting in short stature or dwarfism.When growth hormone excess occurs in adulthood or after the epiphyses of the long bones have fused, the condition is referred to as ______________.Precocious ______________ is the early activation of the hypothalamic-pituitary-gonadal axis, resulting in the development of appropriate sexual characteristics and fertility.______________ disease is a state of hyperthyroidism that is often accompanied by goiter and exophthalmos.______________ syndrome refers to the manifestations of excess cortisol.AcromegalyCushingGravesgrowthpuberty
4 Hypothalamus- Pituitary Axis Releasing hormones from hypothalamus tell the pituitary what to release into the bloodTrophic hormones from the pituitary tell specific peripheral glands to grow and produce their hormonesReleasing HormonesTrophic Hormones
5 Hormone DisordersTertiary: abnormality in stimulation from the hypothalamusSecondary: abnormality in stimulation from the pituitaryPrimary: abnormality in the gland
10 Growth Hormone Sitimulated BY ? Hypoglycemia, fasting, starvation, Stress ??It would seem that adequate energy supply would be needed for Growth ?A baseline level of GH exists during normal nutrition mildly stimulated by Deep Sleep, Exercise, and Protein Consumption. GH stimulates IGF-1During fasting etc. and increased release of GH occurs due to a decrease in GHIH.This produces a protective effect preventing muscle wasting by stimulating lipolysis and FFA metabolism maintaing blood glucose for the CNSWithout GH significantly more muscle wasting occurs
11 Functions of Growth Hormone Promotes GrowthInhibits Insulin
12 Growth Hormone Deficiency Idiopathic GH deficiencyLacks hypothalamic GHRHPituitary tumors, agenesis of the pituitaryCannot produce GHLaron-type dwarfismHereditary defect in IGF production
13 In childhood: gigantism In adulthood: acromegaly Growth Hormone ExcessIn childhood: gigantismIn adulthood: acromegaly
14 QuestionTell whether the following statement is true or false. GH deficiency may result in dwarfism.
15 AnswerTrue Rationale: Laron-type dwarfism is caused by a genetic inability to produce normal amounts of GH. Not True. Normal GH abnormal IGF
16 The Hypothalamus Controls Gonadal Hormone Release Excessive GnRH secretion can be stimulated by:Hypothalamic tumorsPituitary tumorsGiving high levels of GnRH causes the pituitary to become less responsive and reduces the effects of abnormal GnRH secretionhypothalamusGnRHstimulatesanterior pituitaryFSHLHproduction of gametesand gonadal hormones
17 Thyroid Control Thyroid releases T3 and T4 Both are carried by binding proteinsT3 stimulates metabolismT4 is inactive until converted into T3 in the tissuesBoth exert negative feedback on the hypothalamusWhy?
18 Thyroid Insufficiency Due to Lack of I T3 and T4 are not madeThere is no negative feedback to the hypothalamusTRH and TSH continue to be madeIf it is able, the thyroid will grow in response to the TSH
20 QuestionTell whether the following statement is true or false. Simple goiter is caused by increased production of thyroid hormone.
21 AnswerFalse Rationale: Simple goiter is the result of iodine (I) insufficiency. Since I is necessary in order to produce thyroid hormone, a deficiency results in low serum levels of T3 /T4. This causes TSH to stimulate the thyroid gland to make more hormone (which it cannot do because it needs I). The cells of the thyroid gland hypertrophy in an effort to function (make thyroid hormone).
22 Major Adrenal Cortical Hormones CortisolWhat can cause Cortisol Stimulation?Hypothalamus releases ??Causes the Anterior Pituitary to release ??Causes the adrenal cortex to release ??
23 Major Adrenal Cortical Hormones HypothalamusCorticotropin-releasinghormone (CRH)NegativeAnterior pituitaryfeedbackNegativeAdrenal corticotrophicfeedbackhormone (ACTH)AdrenalcortexCortisolTestosteroneAldosterone
25 Adrenal Cortical Disorders Adrenal cortical insufficiency: inability to make all three hormonesPrimary adrenal cortical insufficiency (Addison disease)Secondary adrenal cortical insufficiencyAcute adrenal crisisExcessive adrenal secretionGlucocorticoid hormone excess (Cushing syndrome)HyperaldosteronismCongenital adrenal hyperplasiaDecreased cortisol synthesis; other hormones may be increased or decreased
27 Clinical Manifestations of Cushing Syndrome (high levels of cortisol in the blood)
28 Scenario Three men have adrenal problems. One has hypoaldosteronism, one has an inability to make cortisol, and one has an inability to make testosterone.Question:Which of them is most likely to develop:Hypotension?High CRH levels?Hypoglycemia?Hypervirilization?Decreased libido?Hyperkalemia?
29 Scenario Two women have benign pituitary tumors. One woman has lost weight and complains of being hot all the time; she presents as thin and nervous, with tachycardia and exophthalmosThe second woman has gained weight in her abdomen and presents with a round face and thin arms and legs with stretch marks; she says that at her last checkup her doctor told her she was prediabeticQuestion:What hormones are being secreted by the pituitary tumors in these patients? Why?