MIXTURE:PARATHYROID,ADRENAL CORTEX AND PANCREAS

PARATHYROID GLAND
Parathyroid gland are endocrine gland with four rounded bodies.They are embedded in the dorsal surface of thyroid gland two in each lobe.They weigh about 0.05-0.3gm.They are covered by fibrous capsule.They are made of chief cells and are arranged in channels.Between the cells,blood vessels are present.The hormone secreted by parathyroid gland is Parathormone(PTH) or Collips hormone.The nature of hormone is proteinous.The function of PTH is just opposite to Calcitonin of thyroid gland.
FUNCTION:
a)Increases the permeability of gastro intestinal tract for absorption of calcium.
b)It also increases the permeability of Renal tubule for the reabsorption of calcium from Glomerular filtrate.
c)it is responsible for the normal functioning of nervous and muscular system.
d)It also helps in bone formation and blood clotting.

DISORDERS:
A)HYPOSECRETION:
Hyposecretion of parathormone causes Tetany.It is characterised by twitching of muscles or spasms of the body.It causes decrease in calcium level from 10 mg to 7 mg per 100ml and increase phosphate level from 7 mg to 9 mg.
B)HYPERSECRETION:
Hypersecretion of parathormone causes Osteoporosis.It is characterised by decalcification of bone with increase level in blood.

ADRENAL GLAND:
Adrenal gland are flattened cup like structure.They are two small yellowish structure found on top of kidney at the level of 12th thoracic vertebrae.They measure about 5 cm in length,4cm in breadth and 1 cm in width.Similarly,they weigh 5 gm each.They are covered by Renal Fascia or Fibrous Capsule.The blood vessel of Adrenal gland are Renal and Supra Renal artery or vein.They are triangular or semicircular in shape.
They are found in association with kidney and just above it.Hence,they are also called Supra Renal.Similarly,they are known as 4's gland as it controls salt retention,Sugar metabolism,Sexual function and safety.Adrenal gland is also Emergency gland as it is stimulated during the time of fear,excitment,entertainment etc.
Histologically,it is divided into two parts.They are as follows:
1)Outer cortex(80%):
Adrenal cortex is mesodermal in origin and therefore it function resembles with that of gonad.It is made of steroids.Adrenal cortex is vital for life because it secrete 30 different types of corticoids hormone which are grouped under the three category of mineral corticoids,gluco corticoids and sex corticoids.the secretion of adrenal cortex is under the control of ACTh of anterior lobe of pituitary gland.The three layers of Adrenal cortex from outside to inside are zona glomerulosa,zona fasciculata and zona reticularis(GER).
HORMONES OF ADRENAL CORTEX:
i)MINERALOCORTICOIDS:
These are concerned with metabolism of Na+ and K+ions and water balance.
Hypofunction of mineral corticoids results an imbalance of Na+ and K+ that in turn leads to nervous disorders,convulsions and death(Conn's disease).
Hypersecretion leads to neuromuscular disorders like hypertension.
ii)GLUCOCORTICOIDS:
These are concerned with the synthesis of enzymes that are involved with gluconeogensis(synthesis of glucose from amino acids and fatty acid) and metabolism of carbohydrates.
Its hyposecretion leads to Addison's disease which is characterized by shock,reduced blood pressure,high level of urea in blood and an elevated body temperature,dark bronze colour pigmentation,wwak and anaemic.
Its hypersecretion causes Cushing's disease which is characterized by hyperglycaemia,marked deposition of glycogen in liver,increased protein catabolism,muscle weakness,obesity etc.
iii)SEX STEROIDS:
These are concerned with proper functioning of sex organs and development of secondary sexual characters.These are corticosterone,cortisome and aldosterone.
its hypersecretion causes Adrenal Virilism or adrenogenital syndrome.It produces male type external sexual characters like beards,moustaches and male voice in women etc.

ADRENAL MEDULLA:
Adrenal medulla is ectodermal in origin.So,it functions is similar to that of parasympathetic nervous system and its secretion is known as neurotransmitter.
HORMONES OF ADRENAL MEDULLA:
A)ADRENALINE:
i)It increases the conversion of glycogen to glucose and provide quick supply of energy.
ii)It is used as heart stimulant.
iii)It shows strong bronchodialating effect.
iv)It is used in treatment of asthama and other allergic condition.
B)NON ADRENALINE:
i)It maintains normal control of blood circulation.
ii)It is powerful exciter.
iii)It regulates blood pressure and increase both systolic and diastolic pressure.

PANCREAS:
Pancreas is an irregular,U shaped pinkish gland situated in the curve of duodenum.It is the second largest gland in the human body measuring about 12-15 cm in length and weighs about 40 to 60gm.It is a heterocrine gland as it consists of two distinct region of exocrine and endocrine gland.It is endodermal in origin.
The exocrine part is formed of large number of lobules or acini.Each acinus consists of a number of glandular cells which secrete pancreatic juice which are drained by a pancreatic duct to duodenum.This juice is rich in several enzymes like trypsinogen,amylase and lipase which help in digestion of food.
Several groups of cells called islets of Langerhans found situated in between the acini of pancreas consists an endocrine gland.The Islets of langerhans consists of three types of cell which secrete different hormones:
1)Alpha cell:
The alpha cell secrete Glucagon hormone.The main function of Glucagon hormone is that it increases the blood glucose level by converting the glycogen into glucose in the liver by the process of glycogenolysis.
2)Beta cell:
The beta cell secrete insulin hormone.The main function of the insulin is to decrease the blood glucose level by converting excess glucose into glycogen in the liver by the process of glycolysis.Hypo secretion of insulin hormone causes Diabetes mellitus.
3)Gamma cell:
The gamma cell secrete somatostatin hormone whose function is to inhibit the secretion of both insulin and glycagon.