The Kidney Research Paper

The kidney is one of the vital organs for excretion in the human body. Kidneys are paired; reddish, bean-shaped organ located at the back of the abdomen, one on each side of the spine, at the level of the lowest ribs, just above the waist between the peritoneum walls of the abdomen. The right kidney is slightly lower than the left kidney because the liver occupies considerable space on the left side superior to the kidney (Figure: 1.1). Kidneys are situated retroperitoneal in the abdominal cavity.

An adult kidney is about 10 – 12 cm long, 5 -7 cm wide and 3 cm thick with a mass of 135 – 150gm. Each kidney is joined with the urethras, the tubes that conduct urine to the bladder. At the centre on one side of each kidney is a location known as

About 1.2 millions of nephrons were estimated to be found in each kidney. Each nephron has a renal corpuscle, which lies in the renal cortex, and a renal tubule which runs through a renal pyramid. The renal corpuscle is comprised of a double walled cup shaped epithelial tissue called as Bowman’s capsule formed by the invagination of a tuft of capillaries called as glomerulus. Among the capillaries, the afferent arteriole innervates and the efferent arteriole drains away the Bowman’s capsule. The kidney of resting adult receives 1.2 to 1.3 liters of blood per minute. These structures filter the blood by hydrostatic and osmotic pressure gradients, producing a liquid containing mineral, wastes and water called glomerular filtrate. The purified blood is returned to the body while the filtrate passes into the renal tubule. The blind end of the nephron continues as the renal tubule, which comprises the proximal convoluted tubule (PCT) of 15mm long and 55m diameter, the descending limb of the loop of henle, the ascending limb of the loop of henle and finally the distal convoluted tubule (DCT). The renal tubule particularly distal collecting tubule opens into the collecting duct. As the filterate passes along the renal tubule, a network of tiny blood vessels called the peritubular capillaries reabsorbs useful substance such as Na+, Cl–, H2O and urea from it and secretes

1.2. Definition of kidney stone Kidney stones also called renal calculi are small, solid crystal aggregations of mineral present in the urine. Usually, the waste products present in the urine exist in very small amounts, stay dissolved in the fluid. Sometimes, these waste products become solid and form crystals. These calculi vary in size and can form anywhere in the urinary tract (urolithiasis), kidney (Nephrolithiasis), ureter-the tube connecting the kidneys and the bladder (ureterolithiasis).

Urolithiasis also called calculi or uroliths, is one of the most painful ailments of the urinary tract, formed by deposition of polycrystalline aggregates composed of varied amounts of crystalloid and organic matrix in the kidney, bladder and/or urethra (Figure: 1.4). The formation of such uroliths encompasses several physio-chemical events originate with crystal nucleation, growth, aggregation and retention on renal tubular epithelial surfaces ( Lieske et al., 1994,