Endocri 25 Bio Flashcards
Endocrine
Think hormones and biological cascade. The glands have no ducts.
Steroid hormone
Synthesized from cholesterol.
E.g estro, andro, cortisol, progester, cortisone, aldoster, etc….
Lipid soluble
Polypeptide hormone
Insulin, composed of aa ( with C,H,O,N,S)
Dalton (D): unit of mass of aa
Amine Hormones/ Catecholamines
Made from the aa tyrosine, H2O soluble. A catechol is benzene ring with two hydroxy groups.
Soluble hormone
H2O soluble hormone: binds to cell surface receptor protein
Lipid soluble hormone: binds to an intracellular receptor in cytoplasm or nucleus
Hypothalamus
Link between nervous and endocrine system.
Oxytocin: Stims contraction of the uterus and mammary glands. + feedback
ADH (vasopressin): Antidiuretic hormone
ADH and Oxy are stored in posterior pitutiary.
ADH
H2O retention by kidneys. During severe hemorrhage, by retaining more H2O, this increases blood volume and therefore blood pressure. ADH decrease urine volume.
Anterior Pituitary Gland
Tropic hormones - released to stim other endo glands to release their hormones.
FLAT PG
Growth hormones/ Somatotropin
Inc DNA, RNA, and protein synthesis. Stims the liver to release insulin gf for bone and cartilage growth. Inc blood sugar.
FSH
Ovarian follicle in women, spermatogenesis in males
LH
Stims ovulation, progesterone secretion, corpus luteum formation (f), and testosterone (m)
TSH
Stim the thyroid gland to make and release hormones
ACTH/ Adrenocorticotropic hormone
Stims the adrenal cortex to secrete glucocorticods (cortisol)
Prolactin
Non tropic hormone. Stims mammary gland and milk production. Some link with immune system acting like a growth factor.
Melanocyte Stim Hormone (MSH)
Non tropic hormone. Regs function of melanocytes. Can suppress appetite in humans by binding to receptors in the hypothalamus (similar to Leptin)
T3 and T4
Triiodothyronine (3 Is) and Thyroxine (4 Is, more abundant)
Involved in growth, cell diff, O2 consumption, and basal metabolic rate.
Hyperthyroidism
Inc in metabolism, weight loss, profuse sweating, high blood pressure, irritability.
Hypothyroidism
Cold, gain weight, and lethargy.
Body tries to compensate for this by increasing TSH from the ant pituitary. Constant TSH results in enlarged thyroid = goiter.
E.g. of hypothyroidism
Myxedema: swelling of face, lips, eyelids, and tongue. HR and BP are low.
Hashimoto is autoimmune. (F), middle aged - can lead to heart problems, goiter, and depression.
Cretinism: extreme hypothyroid in fetal life leading to retardation and growth failure..
Calcitonin
Lowers blood Ca2+. Calcitonin will inhibit osteoclastic activity and will promote bone formation by osteoblasts.
Parathyroid (PTH)
Increase in blood calcium.
Bone, kidneys, and intestine.
It also induces some kidney cells to activate Vit.D and take Ca2+ from the intestines.
Hypoparathroidism
Ca2+ conc. are low. Tetany can results and sporadic contractions of skeletal muscles muscles and generalized convulsions.
Pancreas
Both endo ( no ducts) and exo. Makes digestive enzymes and secretes bicarbonate ion.
Insulin and glucagon control blood glucose
Controls the concentration need for homeostasis.
Pancreas cells
Alpha cells (20%): secretes glucagon which causes glycogen breakdown, blood sugar rises Beta cells (70%): secretes insulin which lowers blood sugar. Enhances synthesis of fat, proteins, and transport of aa. Somatostatin (10%): Made by delta cells, inhibition of insulin and glucagon. Inhibitory hormone. These cells are also found in the stomach and small intestine.
DM
Insulin deficiency or decrease response to insulin in tissues. Glucose is excreted through urine.
Type I: autoimmune, beta cell destruction. External insulin.
Type II: Target cells fail to respond normally, though insulin levels are close to normal and glucose uptake is compromised.