Endocrine Flashcards
What are the 5 Endocrine glands?
1-Pituitary 2-Adrenal gland 3-Thyroid gland 4-Parathyroid gland 5-Pineal
What are the 4 endocrine cells?
1-Pancreas
2-Ovary
3-Placenta
4-Testes
What are some unique features of endocrine glands in comparison to other glands?
- Ductless
- Primarily Parenchyma
- abundant blood suplly
What does the anterior pituitary (adenohypophysis) arise from?
Rathke’s pouch
What does the posterior pituitary (neurohypophysis) arise from?
neurophypophyseal pouch of neuroectoderm
What is the pars distalis?
anterior pituitary
what is the pars nervosa?
posterior pituitary
How does the hypothalamo-hypophyseal portal system interact with the Pars Distills (AP)?
-Hypothalmus produces hormones that travel through the portal system to the Anterior Pituitary to stimulate hormone production there (Primary and secondary capillaries)
How does the hypothalamo-hypophyseal portal system interact with the Pars nervosa (PP)?
-Hormones produced by the hypothalamus travel down axons to the posterior pituitary where they are stored and later released
What are the 6 hormones secreted from the Anterior pituitary?
1-hGH (human growth hormone) 2-ACTH (adrenocorticotropin) 3-TSH (thyroid stimulating hormone) 4-LH (leutinizing hormone) 5-FSH (Follicle stimulating hormone) 6-PRL (Prolactin)
What are the three cells common seen in the pars distalis in an H and E stain?
1-Basophils (ACTH, TSH, FSH, LH)
2-Acidophils (PRL, hGH)
3-Chromophobes
What two hormones are stored and released by the pars nervosa?
1-ADH
2-Oxytocin
Nuclei observed in the neurohypophysis belong to what cells?
glia (only axons of neurons are present, Neurosecretory swellings may be present on axons)
What are the two regions of the adrenal gland and what are they derived from?
1-Cortex (mesoderm)
2-Medulla (neural crest)
What does the adrenal medulla secrete?
Catecholamines (epinephrine/norepinephrine)
What are the three zones of the adrenal cortex and what does each secrete?
1-glomerulosa (Mineralcorticoids/aldosterone)
2-Fasciculata (Glucocorticoids/Cortisol)
3-reticularis (sex hormones)
What adrenal cortex hormone is vital for life?
mineralcorticoids/aldosterone
What is the mechanism for aldosterone secretion?
- ACTH stimulates it
- regulated by angiotensin II and K+
What are two adrenal cortex disorders?
1-Cushings syndrome (excess cortisol, weight gain, hyperglycemia)
2-Addison’s disease (low gulco/mineralcorticoids, low BP, fatigues, diarrhea, weight loss)
What disorder is associated with the adrenal medulla?
Pheochromocytoma (neuroendocrine tumor secreting excess catacholamines, eleveated BP, Heart rate, weight loss)
What is synthesized by the thyroid?
- Throxine (T4)
- Tri-iodothyronine (T3)
What fills the central lumen of thyroid follicles?
gelatinous, acidophilic, colloid (which contains glycoprotein thyroglobulin)
What shape are thyrocytes/follicular cells when hypoactive?
squamous (they are cuboidal when active)
What do parafollicular cells (c-cells) secrete?
calcitonin
What is secreted into the colloid/lumen by follicular cells?
-Thyroglobulin and iodide for storage (it is phagocytes later, cleaved into T3 and T4 for secretion)
What hormone levels can be tested for hypothyroidism?
- T3 and T4 would be low
- TSH would be high
What are the primary cells endocrine cells of the parathyroid gland?
-Principal (chief) cells. They produce Parathyroid hormone
What do the pinealocytes of the pineal gland produce?
melatonin (important for light/dark cycles)
