Endocrine Function II: Thyroid, Sex, and Gastrointestinal Hormones; Regulation of Calcium and Phosphorus Levels Flashcards

1
Q

List three thyroid binding proteins

A
  • Throxine binding globulin (TBG)
  • Transthyretin (Thyroxine Binding Prealbmin) (TBPA)
  • Albumin
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2
Q

Which thyroid hormone secreted in the greatest quantity?

A

T4 is the main secretory prodct

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3
Q

Which thyroid hormone is the most potent, biologically active?

A

T3

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4
Q

Describe the structure and clinical significance of increased levels of reverse T3

A

Biologically inactive form favored under stress

?????

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5
Q

List eight physiological effects of thyroid hormones

A
  • Increased oxygen consumption
  • Increases basal metabolic rate
  • Stimulates heart rate/contraction
  • Stimulates protein synthesis
  • Stimulates all aspects of lipid metabolism
  • Affects all aspects of CHO metabolism (4 “Gs”)
  • Increases demands for vitamins and coenzymes
  • Provides negative feedback to TRH and TSH
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6
Q

What is the cause of hyperthyroidism in Graves’ Disease?

A

Autoimmune etiology

  • AutoAbs bind to TSH receptors in thyroid
  • Body thinks it’s getting TSH but is fooled by Abs
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7
Q

What is the cause of hyperthyroidism in toxic multinodular goiters?

A
  • Discrete portions of thyroid are not under normal feedback control
  • No exophthalmopathy but still producing thyroid hormone
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8
Q

What is the cause of hyperthyroidism in solitary toxic adenoma?

A
  • Patients have thyroid nodules that avidly concentrate injected radioactive iodine
  • Benign tumor doesn’t respond to normal feedback control
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9
Q

Nodules that concentrate injected radioactive iodine

A

“Hot nodules”

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10
Q

What causes hyperthyroidism in subacute thyroiditis?

A
  • Inflammation of the thyroid gland
  • Appears to be viral in origin
  • Follicles become inflamed and disrupted
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11
Q

What causes hyperthyroidism in iatrogenic symptoms?

A

Adverse mental or physical conditions caused by a medical procedure/physician

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12
Q

What causes hyperthyroidism in factitious symptoms?

A
  • Disorders that aren’t genuine or natural

- Physical or psychological symptoms are produced under the voluntary control of the patient

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13
Q

What causes hyperthyroidism in TSH-dependent hyperthyroidism?

A

Caused by excess placental hormones (hCG) and TSH-secreting pituitary tumors (tertiary in hypothalamus)

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14
Q

List the symptoms associated w/ hyperthyroidism

A
  • Heat intolerance
  • Flushing
  • Perspiration
  • Increased appetite
  • Weight loss
  • Tachycardia
  • SOB
  • Nervousness
  • Sometimes exophthalmopathy
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15
Q

TSH-independent hyperthyroidism

  • T3 levels
  • T4 levels
  • TSH levels
A
  • T3 levels: ↑
  • T4 levels: ↑
  • TSH levels: ↓
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16
Q

TSH-dependent (2°) hyperthyroidism

  • T3 levels
  • T4 levels
  • TSH levels
A
  • T3 levels: ↑
  • T4 levels: ↑
  • TSH levels: ↑
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17
Q

TSH-dependent (3°) hyperthyroidism

  • T3 levels
  • T4 levels
  • TSH levels
A
  • T3 levels: ↑
  • T4 levels: ↑
  • TSH levels: ↑
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18
Q

Primary hyperthyroidism (TSH-independent) diseases

A
  • Graves’ disease
  • Toxic multinodular goiter
  • Solitary toxic adenoma
  • Subacute (“painless”) thyroiditis
  • Iatrogenic
  • Factitious
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19
Q

What is the treatment for hyperthyroidism?

A

Any anti-thyroid drugs, radio-iodine ablation, or thyroidectomy

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20
Q

List the symptoms of hypothyroidism

A
  • Cold intolerance
  • Dry skin
  • Decreased appetite
  • Muscle weakness
  • Slow heart rate
  • Low BP
  • Weight gain
  • Hoarseness due to thickened vocal cords
  • More common in women
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21
Q

What causes hypothyroidism?

A
  • Diseases (commonly autoimmune) or treatments that destroy thyroid tissue or interefere w/ thyroid hormone biosynthesis
  • Less often caused by secondary (pituitary) or tertiary (hypothalamic) disorders
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22
Q

Primary hypothyroidism diseases

A
  • Adult hypothyroidism
  • Cretinism (pluts endemic goiter)
  • Hashimoto’s thyroiditis
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23
Q

Secondary hypothyroidsm disorders

A

Pituitary or hypothalamus disease/removal/destruction

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24
Q

What are the five causes of adult hypothyroidism?

A
  • Intrinsic disease of the thyroid
  • Total thyroidectomy
  • Complete blockage or thyroid function by irradiation or an antithyroid drug
  • Various diseases
  • Myxedema causes face puffiness, doughy skin, subcutaneous emea
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25
Q

What is the cause of cretinism (neonatal hypothyroidism)

A
  • Failure to develop thyroid gland in utero
  • If mother receives anti-thyroid drugs or radioactive iodine during pregnancy
  • If maternal antithyroid Abs cross placenta (results in mental retardation)
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26
Q

What is the cause of hypothyroidism due to iodine deficiency (endemic goiter)

A
  • W/ little or no iodine, less hormone is made to provide negative feedback to TSH, which is continually trying to stimulate hormone production
  • This eventually causes hyperplasia and large goiters
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27
Q

What causes Hashimoto’s thyroiditis?

A
  • Most common cause of hypothyroidsm
  • Autoimmune, chronic inflammatory disease of thyroid in
    T-hleper cells stimulate B-lymphs to produce antithyroid Abs
  • Defect in organification, causing lymphocytic infiltration of thyroid
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28
Q

What causes secondary/tertiary hypothyroidism?

A

Any factor that affects TSH or TRF production

  • Infection
  • Surgical removal of pituitary or hypothalamus
  • Trauma
  • Cancer
  • Autoimmune destruction of pituitary and/or hypothalamus
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29
Q

Primary hypothyroidism

  • T3 levels
  • T4 levels
  • TSH levels
A
  • T3 levels: ↓
  • T4 levels: ↓
  • TSH levels: ↑
  • TRF (TRH) levels: ?
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30
Q

Secondary hypothyroidism

  • T3 levels
  • T4 levels
  • TSH levels
  • TRF (TRH) levels
A
  • T3 levels: ↓
  • T4 levels: ↓
  • TSH levels: ↓
  • TRF (TRH) levels: ?
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31
Q

Tertiary hypothyroidism

  • T3 levels
  • T4 levels
  • TSH levels
  • TRF (TRH) levels
A
  • T3 levels: ↓
  • T4 levels: ↓
  • TSH levels: ↓
  • TRF (TRH) levels: ?
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32
Q

Define euthyroidism

A
  • Condition in which the serum total thyroid hormone concentrations are abnormal, WITHOUT evidence of clinical thyroid disease
  • Reverse T3 levels are elevated until recovery
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33
Q

What causes euthyroidism?

A
  • Pathogenesis is unknown
  • May include decreased peripheral conversion of T4 to T3 and decreased binding of thyroid hormones to TBG
  • Proinflammatory cytokines may be responsible for some of these changes
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34
Q

Diagnosis of euthyroidism vs. hypothyroidism

A
  • Slight TSH elevation occurs during euthyroid recovery

- Elevation of TSH (> 30 mU/mL) indices true hypothyroidism

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35
Q

Euthyroidism

  • T3 levels
  • T4 levels
  • TSH levels
  • Reverse T3
A
  • T3 levels: ↓
  • T4 levels: ↓
  • TSH levels: normal
  • Reverse T3: ↑ (slight ↑ during recovery)
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36
Q

What is the TRH (TRF) stimulation test used for?

A
  • To distinguish b/w 2° and 3° hypothyroidism
  • Synthetic TRH is administered and TSH response is monitored
  • If no TSH increase → 2°
  • If significant TSH increase → 3°
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37
Q

What do the total T4/T3 assays measure?

A

Measure both free and bound hormone

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38
Q

What is the clinical use of total T3 test?

A

Use for diagnosis and monitoring of hyperthyroid patients w/ suppressed TSH levels and normal FT4 levels

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39
Q

This assay is the most sensitive and specific measure of thyroid activity

A

TSH

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40
Q

What is the clinical use of the thyroglobulin test?

A
  • Primarily to monitor patients w/ FSH cancer (which would be increased)
  • Storage form of thyroid hormone precursors
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41
Q

What is the clinical use of the T3 Uptake test w/ thryoid hormone binding ratio (THBR)?

A
  • Clinical use is to directly or indirectly assess available TBG binding sites, but is not used to diagnose hyperthyroidism or hypothyroidism
  • May be ordered if the patient has an abnormal total T4 or total T3 levels w/ normal TSH
  • The “discrepancy” may be due to ↑ or ↓ TBG levels → patient’s thyroid is functioning just fine
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42
Q

What is the clinical use of total T4?

A

This test by itself, does not provide enough clinical information and must be reported in conjunction with the other thyroid tests

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43
Q

THBR

A

This test provides an approximation of the free hormone concentration in the presence of abnormal TBG levels as TBG or free hormone levels are not easily measured

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44
Q

What factors increase TBG levels?

A
  • Pregnancy
  • Estrogen replacement therapy
  • Oral contraceptives
  • Porphyria
  • Hydatidiforme mole
  • Heroine or methadone abuse
  • Clofibrate
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45
Q

What factors decrease TBG levels?

A
  • Androgens
  • Anabolic steroids
  • Nephrotic syndrome
  • Cirrhosis
  • Corticosteroids
  • Cushing’s syndrome
  • Acromegaly
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46
Q

How does the THBR differentiate true hypothyroidism or hyperthyroidism and states of ↑ or ↓ TBG concentrations w/ normal thyroid function

A

??

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47
Q

Primary hyperthyroidism (thyroid problem)

  • Total T3
  • Total T4
  • FT3
  • FT4
  • TSH
  • THBR
A
  • Total T3: ↑
  • Total T4: ↑
  • FT3: ↑
  • FT4: ↑
  • TSH: ↓
  • THBR: ↓
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48
Q

Primary hypothyroidism (thyroid problem)

  • Total T3
  • Total T4
  • FT3
  • FT4
  • TSH
  • THBR
A
  • Total T3: ↓
  • Total T4: ↓
  • FT3: ↓
  • FT4: ↓
  • TSH: ↑
  • THBR: ↑
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49
Q

Secondary hyperthyroidism (pituitary problem)

  • Total T3
  • Total T4
  • FT3
  • FT4
  • TSH
  • THBR
A
  • Total T3: ↑
  • Total T4: ↑
  • FT3: ↑
  • FT4: ↑
  • TSH: ↑
  • THBR: ↓
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50
Q

Secondary hypothyroidism (pituitary problem)

  • Total T3
  • Total T4
  • FT3
  • FT4
  • TSH
  • THBR
A
  • Total T3: ↓
  • Total T4: ↓
  • FT3: ↓
  • FT4: ↓
  • TSH: ↓
  • THBR: ↑
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51
Q

Tertiary hyperthyroidism (hypothalamus problem)

  • Total T3
  • Total T4
  • FT3
  • FT4
  • TSH
  • THBR
A
  • Total T3: ↑
  • Total T4: ↑
  • FT3: ↑
  • FT4: ↑
  • TSH: ↑
  • THBR: ↑
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52
Q

Tertiary hypothyrodism (hypothalamus problem)

  • Total T3
  • Total T4
  • FT3
  • FT4
  • TSH
  • THBR
A
  • Total T3: ↓
  • Total T4: ↓
  • FT3: ↓
  • FT4: ↓
  • TSH: ↓
  • THBR: ↓
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53
Q

What is the specific diagnostic usefulness of the antithyroidglobulin Ab (TgAb)?

A
  • Hashimoto’s thyroiditis >85% reactivity
  • Graves’ Disease >30% reactivity
  • Tumor marker for recurrence of thyroid cancer
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54
Q

What is the specific diagnostic usefulness of the thyroid peroxidase autoAb (TPOAb)?

A
  • Hashimoto’s thyroiditis 100% reactivity
  • Graves’ Disease 70-80% reactivity
  • Ab itself may be cytotoxic to the thyroid
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55
Q

What is the specific diagnostic usefulness of the TSH receptor autoAb (TRAb)?

A
  • Igs that bind to thyroid cell membranes at or near the TSH-receptor site
  • Either cause hyperactivity of the thyroid (Graves’) or an inability for TSH to stimulate the thyroid (Hashimoto’s)
  • Used for differential diagnosis of hyperthyroidism
  • Used to predict fetal and neonatal thyroid dysfunction due to transplacental passage of maternal TRAb
  • Used to predict the course of Graves’ disease patients on antithyroid drug therapy
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56
Q

of carbons present in estrane

A

18 carbons

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57
Q

of carbons present in androstane

A

19 carbons

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58
Q

of carbons present in pregnane

A

21 carbons

59
Q

What is the analytical importance of the phenolic hydroxyl group on carbon #3 on estrane and its derivatives?

A
  • Estrogens on carbon #3

- Androgens do not have this

60
Q

Estrogen

- Biological effects

A

Primary and secondary sexual characteristics

61
Q

Estrogen

- Site of production

A

Graafian follicle of ovaries

62
Q

Estrogen

- Most potent, physiologically-active estrogen

A

Estradiol (E2)

- Evaluates ovarian fxn

63
Q

Estrogen

- Major post-menopausal estrogen

A

Estrone (E1)

64
Q

Estrogen

- Major estrogen produced during pregnancy

A

Estriol (E3)

- ↓ in fetal distress and measured to monitor progress of pregnancy

65
Q

Estrogen production is stimulated by ____ and ____ from the anterior pituitary

A

FSH; LH

66
Q

Estrogen

- Metabolic activities

A
  • Increases protein synthesis (CBG, TBG)
  • Increases production of HDL and VLDL
  • Promotes development/maturation/fxn of female reproductive system
  • Accelerates linear growth (height)
67
Q

Describe the menstrual cycle w/ the rise and fall of estrogen, FSH, and LH

A

E2 (estradiol) removes negative feedback for FSH/LH which ↑ FSH and estrogen

68
Q

What hormones are responsible for the menstrual cycel?

A
  • GnRH
  • FSH
  • LH
  • Estrogens
  • Progesterone
69
Q

GnRH

- Source

A

Hypothalamus

70
Q

FSH

- Source

A

Pituitary

71
Q

LH

- Source

A

Pituitary

72
Q

Estrogens

- Source

A

Ovary (follicle)

73
Q

Progesterone

- Source

A

Ovary (corpus luteum)

74
Q

GnRH

- Function during menstrual cycle

A

Stimulates pituitary to secrete FSH and LH above a basal level

75
Q

LH

- Function during menstrual cycle

A
  • Surge of LH stimulates follicle to break open and discharge ovum and follicular fluid (containing estrogens)
  • Follicle converted into corpus luteum, which secretes estrogens and gradually increasing amounts of progesterone
76
Q

FSH

- Function during menstrual cycle

A
  • Stimulates ovaries to develop mature follicles (w/ ova)

- Follicles produce increasing high levels of estrogens

77
Q

Estrogens

- Function during menstural cycle

A
  • Causes rapid grwoth of endometrium of uterus
  • Causes breast sensitivity that often accompanies menstrual flow to disapear
  • Rising level of estrogens have negative feedback effect on hypothalamus and GnRH
  • GnRH output reduced, and secretion of FSH and LH inhibited
  • Very high level of estrogens reverses effect on hypothalamus, stimulating it to suddenly release large doses of GnRH
  • GnRH causes pituitary to release sudden surge of FSH and LH
78
Q

Progesterone

- Function during menstrual cycle

A
  • Causes endometrium to become thick, spongy, glandular, and receptive to a fertilized ovum (zygote)
  • Causes breast engorgement (sensitive or painful)
  • Has negative feedback on pituitary
  • Causes a drop in LH production, which results in the degradation of the corpus luteum and a drop in progesterone and estrogen production
  • Lack of progesterone initiates menstrual flow
79
Q

What is the SPECIFIC biological effect of FSH in women?

A

Chooses an egg

80
Q

What is the SPECIFIC biological effect of LH in women?

A

LH stimulates ovulation

81
Q

Discuss the menstrual cycle according to the rise and and fall of estrogen, FSH, and LH

A

?

82
Q

What is the clinical usefulness of continuously monitoring estriol levels urging pregnancy?

A

Indicates status of fetoplacental unit

- Need premature delivery if there’s a sharp decrease in levels

83
Q

Historical method for measuring estrogen

A

Kober Reaction by GM-MS

84
Q

Specific site of progesterone production in pregnant women

A

Placenta

85
Q

Specific site of progesterone production in non-pregnant women

A

Ovarian corpus luteum

86
Q

Three uses for progesterone measurement

A
  • Detect ovulation
  • Detect ovarian tumors
  • Detect placental dysfunction
87
Q

Physiological effects of progesterone

A
  • Stimulates breast development
  • Increases body temperature
  • Prepares uterus for fertilized egg implantation
  • Important for maintenance of pregnancy-
88
Q

Function of progesterone that act in synergy w/ estrogen

A
  • Build up thin endometrial lining
  • Diminish muscular contractions
  • Change quantity/consistency of cervical mucus to allow penetration/viability of sperm
89
Q

Two physiological effects of hCG

A
  • Produced by trophoblasts that become the placenta

- Stimulates progesterone production by corpus luteum

90
Q

Why is the ß-subunit assayed for hCG?

A

α-subunit is identical to those of FSH, LH, and TSH

91
Q

Four uses for the measurement of hCG

A
  • Pregnancy testing
  • Prediction of spontaneous abortion
  • Detection of multiples
  • Detection of follow-up of hCG-producing tumors (testes, ectopic, pregnancy, hydatidiform moles, choriocarcinoma, cancer of prostate, lung, and breast)
92
Q

Two physiological effects of human placental lactogen (HPL)

A
  • Stimulates mammary gland development

- Used to monitor conditions associated w/ decrease in functional placental tissue

93
Q

Is estriol increased or decreased w/ Down Syndrome?

A

Decreased (fetal distress)

94
Q

HPL is a ____ hormone that acts in concert w/ ____ to stimulate hormone production by corpus luteum

A

Protein; hCG

95
Q

hCG is a ____ hormone consisting of α-subunit identical to FSH, LH, and TSH

A

Protein

96
Q

Results from overgrowth of tissue that was to become the placenta

A

Hydatidiform mole

97
Q

Partial and complete molar pregnancies are due to problems during ____

A

Fertilization

98
Q

What are the 19-carbon androgen compounds responsible for?

A
  • Differentiation and maturation of the reproductive organs
  • Secondary sexual characteristics
  • Increased muscle mass and long bone growth
99
Q

Three physiological effects of androgens

A
  • Differentiation and maturation of reproductive organs
  • Secondary sexual characteristics
  • Increased muscle mass and long bone growth
100
Q

Two sites of production of androgens

A

?

101
Q

Three male reproductive abnormalities

A
  • Hypogonadotropic hypogonadism
  • Hypergonadotropic hypogonadism
  • Klinefelter’s syndrome
102
Q

Hypogonadotropic hypogonadism

  • Testosterone levels
  • FSH levels
  • LH levels
A
  • Testosterone levels: ↓
  • FSH levels: ↓
  • LH levels: ↓
    (Indicates pituitary problem)
103
Q

Hypergonadotropic hypogonadism

  • Testosterone levels
  • FSH levels
  • LH levels
A
  • Testosterone levels: ↓ (no negative feedback)
  • FSH levels: ↑↑
  • LH levels: ↑↑
    (Primary failure = small testes)
104
Q

Klinfelter’s syndrome

  • Testosterone levels
  • FSH levels
  • LH levels
A

?

105
Q

What is the SPECIFIC biological effect of FSH in men?

A

Stimulates Leydig cells to produce testosterone and Sertoli cells to produce sperm

106
Q

What is the SPECIFIC biological effect of LH in men?

A

Stimulates Leydig cells in testes to produce testosterone

107
Q

What is the SPECIFIC biological effect of testosterone?

A

Stimulates Sertoli cells to produce sperm and negatively feeds back on the anterior pituitary pituitary and hypothalamus

108
Q

What is the SPECIFIC biological effect of the Sertoli cells?

A

Produce inhibin that negatively feeds back on the anterior pituitary and hypothalamus

109
Q

Feedback loop that exists among GnRH in the hypothalamus, LH and FSH in the anterior pituitary, Leydig and Sertoli cells in males

A

?

110
Q

Vitamin D

- Biologically active form

A

Calcitriol aka 1,25-dihydroxycholecalciferaol (1,25-dihydroxy vitamin D)

111
Q

Vitamin D

- Specific effects on the intestine, kidney, and bone

A
  • Stimulates production of intestinal transport molecules specific for the absorption of Ca2+ and phosphorus
  • Works w/ PTH to enhance bone resorption (osteoCLASTIC activity)
  • Enhances renal reabsorption of Ca2+ and phosphorus
112
Q

Vitamin D

- Net effect on blood calcium and phosphorus concentrations

A

To increase blood levels of both calcium and phosphorus

113
Q

Vitamin D

- Three functions

A
  • Stimulates production of intestinal transport molecules specific for the absorption of calcium and phosphorus
  • Works w/ PTH to enhance bone RESORPTION (osteoCLASTIC activity)
  • Enhances renal reABsorption of calcium and phosphorus
114
Q

PTH

- Specific site of production

A

Parathyroid gland

115
Q

PTH

- Specific stimulus for its release

A

Low ionized Ca2+ levels in blood

116
Q

PTH

- Specific effects on the intestine, kidney, and bone

A
  • ↑ intestinal absorption of Ca2+ and phosphorus by stimulating renal formation of calcitriol (indirect action)
  • ↑ bone resorption (osteoCLASTIC activity)
  • ↑ renal tubular reabsorption of Ca2+
  • ↓ renal tubular reabsorption of phosphorus
117
Q

PTH

- Net effect on blood Ca2+ and phosphorus concentrations

A

To increase blood levels of Ca2+ and decrease levels of phosphorus

118
Q

Calcitonin

- Site of production

A

Synthesized in the parafollicular cells of the thyroid gland

- Hypermagnesemia increases its release

119
Q

Calcitonin

- Specific effects on the intestine, kidney, and bone

A

Opposes vitamin D and PTH

  • ↓ intestinal absorption of Ca2+ and phosphorus
  • Inhibits bone resorption (has osteoBLASTIC activity)
  • ↓ renal reabsorption of Ca2+ and phosphorus
120
Q

Calcitonin

- Net effect on blood Ca2+ and phosphorus concentrations

A

Decrease both Ca2+ and phosphorus

121
Q

Calcitonin

- Two functions

A
  • Stimulate bone formation

- Enhance secretion of filtered Ca2+ and phosphorus

122
Q

Hyperparathyroidism

- Most common cause

A
  • Adenoma

- Hyperplasia

123
Q

Hyperparathyroidism

- Consequences on renal and bone tissue due to hypercalcemia

A

Bone resorption as Ca2+ and phosphorus are released to the blood

124
Q

Hyperparathyroidism

  • Ca2+
  • Phosphorus
  • PTH
A
  • ↑ Ca2+
  • ↑ Phosphorus
  • ↓ PTH
125
Q

Hypoparathyroidism

- Most common primary cause

A

Surgical procedures

126
Q

Hypoparathyroidism

  • Blood/urine Ca2+
  • Phosphorus
A
  • ↓ blood Ca2+
  • Urine Ca2+
  • ↑ blood phosphorus
  • Urine phosphorus
127
Q

Hypervitaminosis

- Blood Ca2+ and phosphorus levels

A

Both are increased

128
Q

List diseases associated w/ vitamin D deficiency?

A
  • Cancer
  • Autoimmune disease
  • Lung disease
  • Infections
  • Schizophrenia
  • Malabsorption diseases
129
Q

Gastrin

- Specific site of production

A

Peptide hormone secreted by G-cells of stomach antrum (lower third) in response to contact w/ food

130
Q

Gastrin

- Function

A
  • Causes HCl production by parietal cells in stomach

- Causes negative feedback as pH ↓

131
Q

List diseases that cause hypergastrinemia?

A
  • Achlorhydria
  • Pernicious anemia
  • Gastrinomas
132
Q

Syndrome associated w/ gastrinomas

A

Zollinger-Ellison Syndrome

133
Q

Secretin

- Specific site of production

A

Secreted by duodenal and upper jejunal intestinal mucosa after contact w/ gastric HCl

134
Q

Secretin

- Function

A

Stimulates pancreas and liver to secrete HCO3 to counteract stomach acidity

135
Q

Cholecystokinin-pancreozymin (CCK-PZ)

- Specific site of production

A

Produced by upper intestinal mucosal cells after contact w/ peptones, fatty acids, and HCl entering duodenum

136
Q

What causes CCK-PZ?

A

Gallbladder contraction and pancreatic enzyme secretion

137
Q

What is the amine hormone derived from the hydroxylation and decarboxylation of tryptophan?

A

Serotonin

138
Q

Serotonin

- Specific site of production

A

Synthesized primarily by the enterchromaffin cells located in the GI tract

139
Q

Serotonin

- Two physiological effects

A
  • Smooth muscle stimulation

- Vasoconstriction (elevates mood)

140
Q

Syndrome associated w/ serotonin-producing tumors

A

Carcinoid syndrome

141
Q

Urinary metabolite of serotonin commonly measured in the lab

A

24-hour collection for 5-HIAA

142
Q

What are the placental hormones?

A
  • hCG
  • Progesterone
  • HPL
143
Q

What are the ovarian hormones?

A
  • Estrogen

- Progesterone