Exam 1 - Posterior Pituitary

what is another name for the pituitary gland

hypophysis

what is another name for the posterior lobe of the pituitary gland

neurohypophysis

what is another name for the anterior lobe of the pituitary gland

adenohypophysis

what are the embryological origins of the posterior pituitary

nervous tissue

what is the function of the posterior pituitary

store and secrete hormones made in the hypothalamus

what is the function of the anterior pituitary gland

receive signaling molecules to synthesize and secrete 7 hormones

what is the posterior pituitary gland derived from

neuroectoderm

what two nuclei does the posterior pituitary receive hormones from

supraoptic and paraventricular

what hormones are stored in the posterior pituitary gland

ADH and oxytocin

what hormone is made by the paraventricular nucleus

oxytocin

what hormone is made by the supraoptic nucleus

adh

what is the primary function of ADH

act on collecting ducts of kidney to facilitate reabsorption of water

what are some factors that will stimulate the release of ADH from the posterior pituitary gland

decrease in bld volume

low BP

increased blood osmolarity (dehydration)

what specific cells of the kidney does ADH stimulate

principal cells of the collecting ducts

what is the secondary effect of ADH

vasoconstriction

what mechanisms of action does ADH use

adenylyl cyclase and phospholipase c

a decrease in extracellular fluid volume of 10% or more is sensed by baroreceptors and is transmitted via what nerves to then stimulate ADH release

vagus and glossopharyngeal

the overall effect of ADH is ___ urine volume and ___ urine concentration

decrease, increase

vasopressin receptor antagonist blocks the action of what? what kind of people use these antagonists?

ADH/vasopressin

CHF, hyponatremia, liver cirrhosis patients

central diabetes insipidus is the decreased output of what? It can be caused by insufficient release of this hormone by the ___ or ___

ADH, hypothalamus, pituitary

what are physical characteristics of central diabetes insipidus

polyuria

dilute urine

hypotension

increased plasma concentration

after the body tries to compensate for central diabetes insipidus, what is increased

aldosterone and renal reabsorption of sodium to restore blood pressure

what structure produces aldosterone

adrenal cortex

what is the function of aldosterone

act on distal tubules and collecting ducts of kidney to increase reabsorption of water and electrolytes

overall, aldosterone ___ blood volume and blood pressure

increases

nephrogenic diabetes insipidus is due to ___ sensitivity to ADH in the principle cells and ___ secretion of ADH from the pituitary. Kidneys (do or don't) recognize ADH leading to ___ concentration of urine

decreased, increased, don't, no

what are some causes of nephrogenic diabetes insipidus

drugs, hereditary, high calcium levels, low potassium levels

thiazide diuretics are used to treat what (they decrease urine volume)

nephrogenic diabetes insipidus

what are some physical characteristics of nephrogenic diabetes insipidus

polyuria

dilute urine

hypotension

increased plasma concentration

ADH levels are elevated

Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is characterized by what

excessive release of ADH usually from autonomous site

patients with Syndrome of inappropriate antidiuretic hormone secretion (SIADH) will often have ___ water reabsorption and __ blood volume with ______ concentrated urine which ultimately __ the plasma sodium

excess, increased, inappropriately, dilutes

what are patients with Syndrome of inappropriate antidiuretic hormone secretion (SIADH) often treated with

ADH antagonist

what are some causes of Syndrome of inappropriate antidiuretic hormone secretion (SIADH)

stroke, head trauma, brain tumor, cancer

what class of hormone is oxytocin

peptide

what mechanism of action does oxytocin use

phospholipase c

what is one of the primary functions of oxytocin during pregnancy

stimulate contractions and dilation of cervix

t/f

during childbirth, oxytocin uses a positive feedback loop

true

after birth, oxytocin plays a large role in what

milk let down

oxytocin also has an effect on emotions and is often referred to as the hormone of ___

love

what role does oxytocin have in males

moving sperm, production of testosterone

overall oxytocin has many roles, name some of them

bonding, sexual response, orgasm, social interactions, milk let down, testosterone production, sperm movement