Lecture 22 Flashcards
What is CRH?
corticotropin-releasing horomone
What is aldosterone?
related to minerals (ie: Na and K) | minimize waste as much as possible
What induces the hypothalamus to release CRH?
stress and circadian rhythm
What is POMC?
precursor of ACTH in the anterior pituitary
What is hypercortisolism?
excess cortisol | Cushing’s syndrome
What are the 3 causes of hypercortisolism?
adrenal tumor (high cortisol) | pituitary tumor (high ACTH) | over-prescribed by doctor
What is Moon Face caused by?
pituitary tumor = high ACTH = high cortisol = red cheeks
How are stretch marks caused?
high cortisol = deposit fats in trunk , protein breakdown under skin causes stretch marks
What is the cause of gigantism?
excess growth hormone
What is a sign of excess growth hormone?
growth of jaw
What are the 2 effects of growth hormones?
hypertrophy and hyperplasia
What is hypertrophy?
increase in cell SIZE
What is hyperplasia?
increase in cell NUMBERS
What are the 4 things bone and soft tissue growth need?
growth hormone | insulin-like growth factor (insulin) | calcium | thyroid hormone
What type of hormone is the growth hormone, tropic or trophic?
trophic
What is the epiphyseal plate within bones?
site of bone growth | area in long bone | gives height
What is the function of chondrocytes?
forms cartilage
What adds length to the bones?
dividing chondrocytes
What cells does the growth hormone act on?
osteoblasts
What are osteoblasts? What are its 2 functions?
bone-building cells | lays down bone on top of cartilage | makes Ca++ phosphate crystals to replace cartilage
How do the hormones calcitonin and parathyroid hormone work opposite to one another?
PTH = take Ca++ out of bone to increase plasma Ca++ levels | calcitonin = takes Ca++ from plasma and puts into bones
Which cells are responsible for bone resorption? What is bone resorption?
osteoclasts | breakdown of bone and release minerals into plasma/blood
What is osteoporosis?
too much Ca++ pulled out of bone | can be due to increase in parathyroid hormone levels and overactivity of osteoclasts | calcitonin is not being effective
What do osteoclasts secrete?
acid and enzymes that dissolve calcium phosphate in bone
Is growth hormone catabolic or anabolic?
anabolic
What is GHRH?
growth-hormone releasing hormone
What 4 factors affect the release of GHRH or somatostatin from the hypothalamus?
circadian rhythm | cortisol | fasting | stress
Which hormone affects cartilage growth?
insulin-like growth factor
What is needed to ensure calcium balance is maintained?
dietary intake equals Ca++ loss in urine/feces
What is Calcitriol?
vitamin D3 = used to treat calcium deficiency
What does calcitriol vitamin D3 allow?
allows absorption of Ca++ into ECF and the body
What controls calcitriol vitamin D3?
parathyroid hormone and prolactin
Where is prolactin synthesized?
anterior pituitary
In regards to the kidneys, how do the parathyroid hormone and calcitonin affect the absorption of Ca++?
PTH = kidney reabsorbs Ca++ | calcitonin = kindey secretes Ca++
What are the 3 hormones that control calcium balance?
calcitonin | calcitriol vitamin D3 | parathyroid hormone
What is Cretinism?
enough growth hormone but not enough thyroid hormone (T3 and T4)
Where is the pancreas located?
under stomach
What are the 2 components of the pancreas?
98% = exocrine tissue | 2% = endocrine tisse
What is the endocrine tissue in the pancreas called?
Islet of Langerhans
What are the 3 types of cells within the Islet of Langerhans?
alpha cells | beta cells | D-cells
What do the alpha cells in the Islet of Langerhans secrete?
glucagon
What do the D-cells in the Islet of Langerhans secrete?
somatostatin (GHIH)
What do beta cells in the Islet of Langerhans secrete?
insulin
What molecules do the exocrine cells of the pancreas secrete? Where are these secreted into and through what?
digestive molecules and bicarbonate into the intestine through ducts
What is bicarbonate? What is it’s purpose in the digestive system?
neutralizes acid and buffers pH of the stomach so intestine can pick up the necessary molecules
The stomach is such an acidic environment, how is the stomach tissue not damaged by the acidic contents?
stomach inner lining has a layer of bicarbonate
What does exocrine mean?
synthesis of something that will be excreted from the body
What does endocrine mean?
synthesis of something that will be released into the body
What is the purpose of the vascularization of the Islet of Langerhans in the pancreas?
insulin and glucagon can be directly released into bloodstream after synthesis
Where do exocrine cells release their synthesized products into?
pancreatic duct into small intestine
Which hormone (insulin or glucagon) does the fed state have a high level of?
fed state = high level of insulin
What are the 4 effects of the fed state?
high glucose oxidation = make energy | increase synthesis of : glycogen - proteins - fats (will be stored)
Which hormone (insulin or glucagon) does the fasted state have a high level of?
fasted state = high level of glucagon
What are the 3 effects of the fasted state?
break down glycogen | make glucose from fat and proteins | ketogenesis
What is ketogenesis?
a lot of protein but no glucose = breakdown protein to make glucose out of it = produces ketones
What is needed for glucose to be absorbed into intestine?
insulin
What is the neurotransmitter and receptor for parasympathetic output?
acetylcholine and AChR
What triggers the alpha cells of the pancreas?
when glucose levels go down
What is the characteristic of Type I diabetes?
pancreas not functioning = can’t make insulin
What is the treatment plan for people with Type I diabetes?
insulin injection = allows glucose transport to be active
What is the characteristic of Type II diabetes?
insulin receptor defect = not recognize insulin
What is Diabetes Mellitus?
excess plasma glucose levels
What are the 4 factors that cause diabetes?
sedentary lifestyle | excess food | obesity | genetics (most common)
What are 2 signs associated with diabetes?
sweet urine smell | always thirsty
What are abnormal levels of plasma glucose (mg/dL)
130 prior meal | rises up to 400 post-meal
What are the 3 nutrients in which its levels are increased after a meal?
fats | glucose | proteins
What are the 4 effects in people with Type I diabetes after a meal is absorbed?
tissue loss | hyperglycemia | metabolic acidosis | low blood volume and blood pressure
What is hyperglycemia in Type I diabetes and what does it lead to?
accumulation of sugar in the blood | leads to increase in osmolarity
What is metabolic acidosis in type I diabetes?
body tries to break down tissue to make glucose | increase ventilation
What happens in Type I diabetes that can lead to coma or death?
circulatory failure due to low blood pressure and blood volume
