Chapter Two: Hormones of the Endocrine Glands Flashcards
Pineal gland
Melatonin
Gonadal function
Seasonal breeding
Skin pigmentation
Thyroid
Thyroxin (T4) - Metabolic rate
Triiodothyronine (T3) - Brain development, bone growth
Calcitonin - Reduces blood clacium
Parathyroid
Parathyroid hormone - Elevates blood Ca++
Thymus (above the heart)
Thymosins - Regulate immune system, release cytokines
Heart
Atrial Netiuretic peptide (ANP) - Reduces blood pressure
B-Type Natiuretic peptide - Marker for congestive heart failure
Pancreas (Islets of Langerhans)
Insulin (beta cells)
Glucagon (alpha cells)
Somatostatin (delta cells)
Pancreatic polypeptide (F cells)
Regulation of glucose levels
Adrenal cortex
Mineralocorticoid - Na+ retention
Glucocorticoid - Stress anti-inflammatory
Sex steroids - Puberty, 2nd sex characteristics, sex differences
Adrenal medulla
Epinepherine - Stress reponse (heartrate, O2)
Norepinepherine - Blood pressure increase
Kidney
Vitamin D - Maintains blood calcium levels, bone and immune system
Erythropoietin - Production of red blood cells (erythrocytes)
Important GI hormones
Gastrin - Stimulation of hydrochloric acid, stimulates pancreatic enzyme, increasing intestinal motility, stomach
Ghrelin - Increases hunger, stimulates feeding, stimulates growth hormone release, stomach
Cholecystokinin - stimulates vagus nerve to signal ‘fullness’, duodenum
Secretin - Stimulates bile secretion, after digested food has passed through the duodenem
Testes
Leydig cells - androgens (testosterone), male sex characteristics
Sertoli cells - Inhibin and activin, control FSH secretion
Ovary - Granulosa cells
Estradiol - Female sexual characteristics; menstrual cycle
Ovary - Luteal cells
Progesterone - Uterine function - pregnancy
Inhibin, Actin, Relaxin - Controls FSH during pregnancy
Placenta
Human chorionic gonadotropin - secreted after implantation
Adipose tissue
Adipokines, control of body weight
A. Leptin, reduce food intake
B. Insulin resistance
Muscle
Myostatin, interleukins, irisin - control of fat mass and insulin secretion
Bone
Osteocalcin - insulin secretion and testosterone levels
Liver
Fetuin-A, insulin control
FGF-21
Betatrophin, B-cell proliferation
Three main classes of hormones
Protein hormones (GH, ACTH, LH, FSH, GnRH)
Amine hormones (epinepherine, norepinepherine, melatonin)
Steroid hormones (cortisol, estrogen, progesterone, androgens)
Protein hormone action
Hormones enter through receptor –>
secondary messenger inside the cell –>
Altered cell function, biological effects
Steroid hormone action
Enter through lipid bilayer –>
Attach to steroid receptor which enters the nucleus –>
New protein production and biological effects
