CHP 18 Flashcards
Where does both the nervous system and endocrine system interact?
The pituitary gland and the hypothalamus.
The hypothalamus regulates secretions of the____ _____ (____) and the ____ ____ ( ____).
Anterior pituitary (adenohypophysis), Posterior pituitary (neurohypophysis).
The ____ ____ (____) is an extension of the hypothalamus via the infindibulum.
Posterior pituitary (neurohypophysis).
The anterior hypophyses produces _ major hormones that:
9; Regulate body functions and the secretions of other endocrine glands.
The ____ ____ secreters neuropeptides.
Posterior pituitary.
The ____ ____ consists of 3 areas with indicting boundaries:
Pars distills, pars intermedia, and parts tuberalis.
Describe the first two steps in the process of hormone secretion/inhibition from neurons of the hypothalamus. (Anterior Pituitary)
Stimuli within the nervous system regulate the secretions of releasing/inhibiting hormones from neurons of the hypothalamus. These hormones pass through the hypothalamohypophysial portal system to the anterior pituitary.
Describe the last two steps in the process of hormone secretion/inhibition from neurons of the hypothalamus. (Anterior Pituitary).
Releasing hormones and inhibiting hormones leave capillaries and stimulate or inhibit the release of hormones from anterior pituitary cells. In response to releasing hormones, anterior pituitary hormones travel in the blood to their target tissues.
What is unique about Posterior Pituitary hormone release/inhibition.
Stimuli within the nervous system cause hypothalamic neurons to either increase or decrease their AP frequency.
ADH
A hormone of the posterior pituitary, also called vasopressin. Released in response to water concentration, changes in BP, and electrolyte concentration.
Osmoreceptors
Detect changes in intercellular osmolality, or the relative concentration of electrolytes and water. Specialized neurons of the hypothalamus.
Baroreceptors
Detect changes in BP. Found in the walls of the atria of the hear, large veins, carotid arteries, and aortic arch.
Increasing ADH acts of the ____ ____, to increase:
Kidney tubules; water reabsorption, resulting in reduced urine volume & osmolality, and decreased blood osmolality. This helps maintain blood osmolality and volume.
Stretch of the uterus and the uterine cervix or stimulation of the breasts’ nipples increase APs in axons of this hormone.
Oxytocin.
____ _____ is an anterior pituitary hormones that stimulates the uptake of amino acids; protein synthesis.
Growth hormone.
____ _____ stimulates breakdown of fats to be used as an anergy source but stimulates synthesis of glycogen: glucose sparing.
Growth hormone
GHRH targets
most tissues of the body.
In response to stress, low blood glucose, or high BP, ____ ____ ____ may occur.
Growth hormone inhibition.
The secretion and storage of T3 and T4 by the anterior pituitary is a result of what hormone?
Thyroid stimulating hormone.
__ and __ inhibits TRH and TSH secretion.
T3, T4.
CRH from the hypothalamus causes the release of ____.
ACTH.
____ causes increase in production of melanin.
ACTH.
____ binds directly do melanocytes of the skin, causing increase in the production of melanin.
ACTH.
These four molecules all derive from the same large precursor molecule when stimulated by CRH.
ACTH, MSH, endorphins, and lipotropins.
MSH causes:
melanocytes to produce more melanin.
______ cause adipose cells to catabolize fat.
Lipotropins.
____ act as an analgesic (pain killer), produced during times of stress.
Endorphins.
Gonadotropins
Glycoprotein hormones that promote growth and function of the gonads.
Three gonadotropins are:
LH & FSH (prod. of gametes & reproductive hormones), and prolactin (milk prod.).
__ and ___ regulate production of gametes and reproductive hormones.
LH, FSH.
GnRH from the hypothalamus stimulates:
LH and FSH secretion.
Thyroid gland
One of the largest endocrine glands. Highly vascularized. Iodine enters follicular cells by active transport.
Follicles
Follicular cells surrounding thyroglobulin/thyroid hormones.
Parafollicular cells (between follicles) secrete:
Calcitonin, which reduces CA2+ in body fluids when CA levels are elevated.
__-__% of __ is converted to __ in cells. __ is more potent.
33-40%, T3, T4; T4.
Normal growth of many tissues are dependent on the presence of ____ hormones.
Thyroid.
Secretory products of the Adrenal medulla are ____ and ____.
Epinephrine, Norepinephrine.
_______ is a neuropeptide that causes:
Increase in blood levels of glucose, fat breakdown in fat tissue, and dilation of blood vessels in skeletal & cardiac muscles.
Neuropeptides
increase heart rate, and force of contraction, causes blood vessels to constrict in skin, kidneys and other viscera.
From three layers of the adrenal cortex are the:
Zona glomerulosa, Zona fasciculata, and Zona reticularis.
Zona ________ produces
Glomerulosa; Aldosterone (mineralocorticoids).
Zona ________ produces
Fasciculata; Cortisol (glucocorticoids).
Zona ________ produces
Reticularis; Androgens.
____ increases rate of sodium reabsorption by kidneys increasing sodium blood levels.
Aldosterone
____ increases fat and protein breakdown, increases glucose synthesis, decreases inflammatory response.
Glucocorticoids
____ are then converted to testosterone by peripheral tissues and stimulate pubic and axillary hair growth and sex drive in females.
Androgens.
Pancreas
Located along the small intestine and stomach. Has both endocrine and exocrine functions.
Exocrine gland
Produces pancreatic digestive juices.
Endocrine gland
Consists of pancreatic islets. Composed of alpha (Glucose secretion), beta (insulin secretion), and delta cells (somatostatin secretions).
