Endocrine System: Adrenal Glands and Pancreas

paired,present one above kidney ,composed of two types of tissues (outer- adrenal cortex inner - adrenal medulla)

hormone of medulla are chemically catacholamines(adrenaline (epinephrine) and noradrenaline (norepinephrine) these are secreted in response to stress of any kind and during emergency situation this are called emergency hormone or hormones of fight or flight functions: equip body to face and emergency situation these increase alertness,cause papillary dilation piloerection (raising of hair),sweating increases heart beat strength of heart contraction and rate of respiration increases concentration of glucose in blood by stimulating breakdown of glycogen to glucose (glycogenolysis) also stimulate breakdown of lipids and proteins(lipolysis and proteolysis)

three layers inner (Zona reticularis) middle (Zona fasciculata) outer (Zona glomerulosa) hormones of adrenal cortex are steroids and are commonly called corticoids

secreted by the endocrine tissue of zona glomerulosa, aldosterone is the main mineralocorticoid , mineralocorticoids regulate the level of water and electrolyte in our body aldosterone mainly act on the renal tubules , stimulate reabsorption of Na+ and water and promotes the excretion of K+ and phosphate ions through renal tubules

regulate the level of electrolyte in body fluids regulate the volume of body fluids regulates osmotic pressure and blood pressure

glucocorticoids are mainly involved in carbohydrate metabolism, glucocorticoids are secreted by the endocrine tissue of zona fasciculata, cortisol is main glucocorticoid , glucocorticoids stimulate gluconeogenesis, lipolysis and proteolysis,inhibit cellular uptake and utilisation of amino acid, glucocorticoids increase blood glucose level through gluconeogenesis, maintains cardiovascular system and kidney functions , cortisol stimulates RBC production , glucocorticoids (mainly cortisol)produces anti inflammatory reactions and suppress immune system, cortisol is anti allergic and is used in the treatment of allergic diseases like asthma

sex corticoids are steroids secreted by zona reticularis ,sex corticoids play a role in growth of axial hairs pubjc hairs and facial hairs during puberty

due to hypo secretion of adrenal cortex hormones ,characterised by altered carbohydrate metabolism causing acute weakness and fatigue

pancreas is a composite gland ,it has exocrine and endocrine functions (heterocrine gland) , the endocrine pancreas consists of Islets of langerhans , there are about 1 to 2 million Islets of langerhans in a normal human pancreas pancreatic Islets represent 1 to 2 percent of pancreatic tissue

two main types of cells in Islets of langerhans alpha cells with secrete glucagon and beta cells which secrete insulin

peptide hormone secreted by pancreatic Islets, plays important role in maintaining the normal bolld glucose levels glucagon acts mainly on the liver cells (hepatocytes)

glucagon acts on hepatocytes of liver and increases blood glucose level (hyper glycemia through) stimulating glycogenolysis (a metabolic pathway that converts glycogen to glucose) stimulating gluconeogenesis (synthesis of glucose from non glycogen source like protein and fat reduce cellular uptake and utilisation of glucose glucagon increases blood glucose levels and hence called hyperglycemic hormone

secreted by beta cells of pancreatic Islets insulin is a peptide hormone which plays a major role in the regulation of glucose homeostasis

target cells of insulin - hepatocytes and adipocytes insulin increases glucose permeability of hepatocytes and adipocytes and enhance cellular glucose uptake and utilization rapid movement of glucose from blood to hepatosis and deposites result in decreased blood glucose level( hypoglycemia) incense stimulates conversion of glucose to glycogen (glycogenesis) in target the glucose homeostatis in blood is this maintain jointly by the two hormones insulin and glucagon

caused due to deficiency of insulin characterised by the inability of body to remove access glucose from Blood resulting in hyperglycemia prolonged hyperglycemia leads to a complex disorder called Diabetes mellitus Diabetes mellitus is associated with loss of glucose through urine glycosuria formation of harmful compounds known as Ketone bodies which are as created through urine ketonuria excessive urination and excessive thirst diabetic patients are successfully treated with insulin therapy

insulin dependent diabetes mellitus (IDDM) an autoimmune disorder in which antibodies destroy beta cells of pancreatic Islets causing insulin deficiency

an age related disorder due to decline in insulin production or due to inability of target cells to respond to insulin

a pair of testis is positioned in the scrotal sacs (outside the abdomen) testis performs dual functions As primary sex organ- it is involved in spermatogenesis As an endocrine gland-, it produces steroids hormones called androgens testes is formed of seminiferous tubules and interstitial (stromal)tissue leydig cells(interstitial cells);in the intertubular spaces (stroma) produce hormonesbcalled androgens (mainly testosterone)

androgens regulate the development maturation and functions of the make accessory sex organs like epididymis vas deferens seminal vesicle prostate gland urethra etc androgens stimulate muscle growth stimulate the growth of facial and axillary hairs promotes aggressivenessband development of low pitch of voice androgens play a major role in the process of spermatogenesis (formation of spermatozoa) androgens act on the central nervous system and influence the male sexual behaviour(libido) these hormones produce anabolic (synthetic) effects on protein and carbohydrate metabolism androgen promote erythropoiesis

female have a pair of ovaries located in the abdomen as a primary female sex organ ovary produces and released one ovum during each menstrual cycle ovary is composed of ovarian follicles and stromal tissues ovary produces two group of steroids hormones estrogen and progesterone estrogen is mainly synthesized and secreted by the growing ovarian follicles after ovulation the ruptured follicles converted to a structure called corpus leuteum which secretes progesterone and estrogen (progesterone is the predominant hormone of corpus leuteum)

promotes: growth and activities of female secondary sex organs development of growing ovarian follicles appearance of female secondary sexual characters like development of high pitched female voice development of mammary gland

progesterone support pregnancy (pregnancy hormone) it also acts on the mammary glands and stimulate the formation of alveoli (sac like structure which store milk) and milk secretion