Endocrine Ch. 16 Flashcards
1
Q
Layers of Adrenal cortex (from top to bottom)
Get My Freakin Gun Right Away
A
- Capsule:
- Zona glomerulosa: mineralocorticoids (aldosterone)
- Zona Fasciculata: glucocorticoids (cortisol)
- Zona Reticularis: androgens (SEx hormones) (dehydroepiandrosterone DHEA, adrenosterone)
2
Q
Adrenal medulla (cells and hormones)
A
- Chromaffin cells (named for their characteristic brown staining with chromic acid salts)
- 80% epinephrine (adrenaline), 20% norepinephrine (noradrenaline).
- Catecholamines derived from Tyrosine
3
Q
Thyroid (hystology = 3 features)
Thyroid “Shield”
A
- Follicles: absorbs selectively iodine iones (I-). Storages iodine in thyroglobulin. The follicular lumen is filled with colloid (thyroglobulin with attached iodine = precursor for Thyroid hormone)
- Follicular cells: surround the follicles (single layer of thyroid epithelial cells). Secrets T3 20% and T4 80% (T3 is 10 time more potent than T4). Most cells convert T4 to T3.
- Parafollicular cells: located in spaces between the spherical follicles. Secrete calcitonin. Lowers calcium and phosphate concentration in plasma and inhibits bone resorption.
4
Q
Pituitary gland (division, secretions)
A
- Anterior pituitary:
- Growth hormone (somatotrophin)
- Thyroid-stimulating hormone (TSH)
- Adrenocorticotropic hormone (ACTH). Corticotropin
- Beta-endorphin.** Corticotropin**
- Prolactin (PRL)
- Luteinizing hormone (LH)
- Follicle-stimulating hormone (FSH)
- Posterior pituitary:
- Oxytocin
- Antidiuretic hormone (ADH) or vasopressin.
- the middle part
- Melanocyte-stimulating hormone (MSH). Production of melanin. MSH signals to the brain have effects on appetite and sexual arousal. Stimulates melanogenesis; facilitates learning and memory; affects inflammatory and immune responses and peripheral nerve regeneration.
5
Q
Addison’s disease
A
- Hypofunction of the adrenal cortex.
- Too little cortisol and often insufficient levels of aldosterone as well.
- Low B.P.
- Pigmented skin
6
Q
Aldosterone
A
- Works in the distal convoluted tubule DCT
- Increases water and Na+
7
Q
Cushing’s disease
A
- Hyperfunction of adrenal cortex
- High BP
- Obesity
- Tumor grows on the pituitary gland and produces excessive amounts of ACTH
ACTH travels through the blood to the adrenal glands, - Adrenal glands release excessive amounts of cortisol, which travels throughout the body
- The level of cortisol builds up over time to cause the signs and symptoms of Cushing’s disease (physical, emotional, cognitive)
8
Q
Pituitary gland (location)
A
- In the sphenoid bone,
- On the Cella Turcica
9
Q
Posterior pituitary
A
It is the storage site for the hormones produced int he hypothalamus
- ADH (acts in the collecting ducts)
- Oxytocin (acts on:
- Femails for contractions during birth and breastfeeding
- Males for smooth muscle of the Vas deferens –> strong contractions during ejaculation
10
Q
Diabetes insipidus
A
- Caused by deficiency of vasopressin (ADH) from posterior pituitary
- Characterized by excessive thirst and excretion of large amounts of severely diluted urine.
11
Q
Anterior pituitary
A
- Somatotrophin = Growth hormone (50% of cells in Anterior pituitary)
- ACTH (adrenocorticotrophic hormone) acts on the adrenal cortex (20 % of cells)
- Gonadotrops (5% of cells)
- Women : FSH (follicle stimulating hormone –> strogen) and LH (luteinizing hormone –> progesterone)
- Males: FSH (follicle stimulating hormone –> tubules in testes produce sperm) and LH ( acts on interstitial cells –> testosterone)
- Thyrotrophs: TSH (5%) (thyroid stimulating hormone) –> T3 and T4 for metabolic rate and nervous system development.
- Mammotroph: (20%) Prolactin (mammary gland –> secrets milk)
12
Q
Where is ova produced?
A
- Ova originates in the yolk sac
- The ovaries only house the ova and maturation.
13
Q
What hormones are produced in the ovary?
A
- Progesteron
- Estrogen
14
Q
What hormones are produced in the testes?
A
- testosterone
15
Q
Parathyroid hormone (PTH)
A
- Increases Ca++ in the blood
- Acts on osteoclast by increasing bone resorption.
