Endocrine Physiology Flashcards
what are the two types of glands?
endocrine and exocrine
what do exocrine glands secrete?
substances to the outside (e.g digestive glands, sweat glands)
Do ducts allow secretion?
YEAH
what do endocrine glands secrete?
hormones to the blood (e.g thyroid, gonads, pituitary
Are ducts required in endocrine glands?
no
nonpolar hormones?
- cant dissolve in plasma -> carrier proteins
- pass through PM DIRECTLY into cell
what are examples of nonpolar hormones?
steroids and thyroid hormones
where are steroids derived from?
cholestorol
where are thyroid hormones derived from?
tyrosine
polar hormones?
- dissolve easily in plasma
- can’t pass through PM, must use receptor
What are examples of polar hormones?
amines (melatonin), polypeptides (insulin), proteins (growth hormones)and glycoproteins (LH)
what is a pituitary gland also called?
hypophysis
where is the pituitary gland located?
directly below hypothalamus (connected by infundibulum)
how many glands are in the pituitary gland?
2
what are the names of the 2 pituitary glands?
anterior and posterior
what is AP (or adenohypophysis) derived from?
oral epithelium
what is the connection between AP and the hypothalamus?
there is no neural connection between them
what is PP (or neurohypophysis) derived from?
brain
what is the connection between PP and the hypothalamus?
axons extend from the hypothalamus
are hormones from PP secreted or produced?
secreted
what is an example of an antidiuretic hormone (ADH)?
vasopressin
what does the stimulus equal in an ADH?
high osmolality (dehydration), increased blood pressure
what is the target of ADH?
kidney, arterioles
what is the action of ADH?
H2O retention, vasocontriction
what is an example of a stimulus for Oxytocin?
baby sickling
what is the target for oxytocin?
- uterine smooth muscle -> contraction at parturition
- mammary alveoli -> milk ejection (let down)
- brain -> maternal bonding
- men = sperm transport
what are the two hormones secreted by PP?
antidiuretic hormone and oxytocin
what does the AP do?
produces and releases hormones
what kind of hormones does the AP produce/release?
growth hormones, thyroid stimulation hormone, and adrenocorticotropic hormone
growth hormones (GH)
- i.e somatotropin
- promotes tissue and organ growth, synthesis
thyroid stimulating hormone (TSH)
- i.e thyrotropin
- stimulates the thyroid to secrete thyroxine (T4) and triiodothyronine (T3)
adrenocorticotropic hormone (ACTH)
- i.e corticotropin
- stimulates the adrenal gland to release steroids (e.g cortisol)
follicle-stimulating hormone (FSH)
- i.e. folliculotropin
- women -> stimulates growth of ovarian follicles
- males -> stimulates production of sperm in testes
Luteinizing hormone (LH)
- i.e. luteotropin
- women -> stimulates ovulation and formation of corpus luteum in ovaries
- men -> stimulates interstitial Leydig cells of testes to secrete testosterone
prolactin (PRL)
- women -> stimulates milk production by mammary glands
- roles in reproduction and kidneys of men and women
what is the system that controls the AP?
hypothalamo- hypophyseal portal system
what does the hypothalamus secrete?
releasing hormones
corticotropin-releasing hormone (CRH)
AP-> ACTH
thyrotropin-releasing hormone (TRH)
AP -> TSH
gonadotropin-releasing hormone (GnRH)
AP -> FSH & LH
growth hormone-releasing hormone (GHRH)
AP -> GH
do all or some hypothalamic hormones inhibit AP?
some
what does hypothalamic control of AP apply to?
AP hormones that DON’T stimulate hormone production by other glands
somatostatin of hypothalamic control of AP
AP blocks production of GH
prolactin-inhibiting hormone (hypothalamic control of AP) (PIH)
AP blocks production of PRL
control of AP hormone secretion
- negative feedback inhibition
- eventually, reach hypothalamus and AP
- inhibit the production of releasing and stimulating hormones
- anabolic steroid abuse