Lecture One Flashcards
What are the four methods of hormone delivery
Endocrine Neuro endocrine Paracrine Neurocrine Autocrine
How does endocrine signaling work
Hormone secretion into blood by endocrine gland to distant target cell
Paracrine signaling
Secretory cell signals adjacent target cell. Extracellular signals to receptors
Autocrine signaling
Target sites on same cells, extracellular signal to multiple receptors
Signaling by plasma membrane attached proteins
Signaling cell to adjacent cell via receptor and membrane attached signal
Endocrine postulates (5)
Gland must produce internal secretion
Methods of detecting internal secretion must be available
Extracts must be produced from which a purified hormone can be obtained
The pure hormone must be isolated, its structure determined and its synthesis achieved
Hormone acts on specific target cells such that excess or deficiency results in a specific phenotype
Pituitary anterior lobe hormones
Luteinizing hormone, follicle stimulating hormone, prolactin, growth hormone, adrenocorticotropin, beta lipotropin, beta endorphin, thyroid stimulating hormone
Pituitary intermediate lobe
Melanocyte stimulating hormone, beta endorphin
Pituitary posterior lobe
Vasopressin or anti diuretic hormone, oxytocin
Thyroid
T4 and T3, calcitonin
Parathyroid
Parathyroid hormone
Adrenal cortex
Cortisol, aldosterone, dehydroepiandrosterone, androstenedione
Adrenal medulla
Epi, norepinephrine
Gonads testis
Testosterone, estradiol, androstenedione, inhibin, activin, mullerian inhibiting substance
Gonads ovary
Estradiol, progesterone, testosterone, androstenedione , inhibin, activin, FSH releasing peptide, relaxin, follistatin
Placenta
Human chorionic gonadotropin, human placental lactogen, progesterone, estrogen
Pancreas
Insulin, glucagon, somatostatin, pancreatic polypeptide, gastrin, vasoactive intestinal peptide
Pineal
Melatonin, biogenic amines, several peptides
Brain (hypothalamus)
Corticotropin releasing hormone, thyrotropin releasing hormone, Luteinizing hormone releasing hormone, GH releasing hormone, somatostatin, growth factors^a, transforming growth factor beta, insulin like growth factor 1
Heart
Atrial natriuretic peptides
Kidney
Erythropoetin, renin, 1,25-dihydroxyvitamin D
Liver, other organs, fibroblasts
IGF-I
Adipose tissue
Leptin
GI tract
Cholecystokinin, gastrin, ghrelin, secretin, vasoactive intestinal peptide, enteroglucagon, gastrin-releasing peptide
Platelets
Platelet derived growth factor, TGF beta
Macrophages, lymphocytes
Cytokines, TGF beta, pro-opiomelanocortin derived peptides
Various sites
Epidermal growth factor, TGF alpha, neuregulins, neurotrophins
Five different categories of hormones
Amines, thyroid hormones, polypeptides, proteins, steroids
Half life of amine
2-3 min
Half life of T4
6.7 days
Half life of T3
0.75 days
Polypeptides
4-40 minutes
Proteins
15-170 minutes
Steroids
4-120 minutes
Two classes of hormone receptors
Intracellular receptors and cell surface receptors
How many groups in cell surface receptors
Two
How many groups in intracellular receptors
Two
Two cell surface receptor groups
Linked to TK and linked to G protein
Two groups of intracellular receptors
Cytosolic and nuclear
Two subgroups of linked to TK surface receptors
Growth factor receptors intrinsic TK
Cytokines receptors recruit TK
Two subgroups of surface receptors linked to G proteins
Adenylate Cyclase
PLC
