70 years old female patient with Alzheimer's disease was lost in a market and was found only on the next day. The patient has not drunk or eaten anything for the past 24 hours. On examination, she is mildly confused and dehydrated. Blood glucose levels are normal. Which one of the following hormone is responsible for normal blood glucose levels and acts on the intracellular receptors?
Answer: b) Cortisol.EFFECTS OF HYPOGLYCEMIA (Insulin Shock)* Complete inhibition of insuling secretion occurs below the blood sugar levels 80mg/dl.* Glucagon, GH, Epinephrine secretion occurs below the blood sugar levels of 70mg/dl.* COMA- levels less than 30mg/dl.* CONVULSIONS-levels less than 20mg/dl.* PERMAMENT BRAIN DAMAGE & DEATH- levels less than 10mg/dl.Effects of glucon & epinephrine: rapid short lived.Effects of growth hormone & cortisol: slow, long lasting. HormonesMechanism of actionExamplesProtein (peptide) hormonesCombines with cell surface receptors and may increase adenylyl cyclase activity via G proteins & increases intracellular cAMP.Calcitonin, ACTH, PTH, Glucagon, LH, FSH, ADH,TSH, SomatostatinModify guanylate cyclase activity via G proteins & alters intracellular cAMPNO, ANP, Guanylin| intracellular Ca2+/ IP3 / DAGOxytocin, Ach, GnRH| kinase/ Phosphatase activityInsulin, Prolactin, GH,IGF-I &IIIncrease serine or threonine kinase activityinhibin, activinSteroid hormonesBinds & forms a complex with cytoplasmic receptor. Complex enters the nucleus & regulates protein synthesis.Androgen, Estrogen, Progesterone, Cortisol Aldosterone, Vit-A & DThyroid hormonesBinds & forms a complex with nuclear receptor & regulates protein synthesisThyroxine
Epinephrine
Cortisol
Growth hormone
Glucagon
Nervous System