The Kidney

The Kidney is an organ most often even, located in the abdomen, behind the peritoneum, between the 11th back vertebra and the 3rd lumbar (for the left kidney) and the 12th and the space between the 3rd and the 4th lumbar (for the right kidney). The kidney is therefore rear-view mirror-péritonéal. He assures, by filtering and excretion of urine, the hydroelectrolytic equilibrium (homéostasie) of blood and organism in general. The single kidney (5 % of the individuals) is necessary to live and in that case it is most often about the better vascular, right kidney contrary in left and à the presence of the Quadrilateral of Rogié which favours the venous stagnation and has repercussions at left genital level.

The kidney also has a function endocrine (érythropoïétine, system rénine-angiotensine-aldostérone). Kidneys are covered by small glands which they call adrenal. This one are constituted of a cortex (cortico-adrenal), secrétant principally corticostéroïdes and party médullaire (médullo-adrenal), secrétant some adrenalin.

What is the nephron ?

A néphron is the structural and functional basic unit of the kidney. It is a slim tubule consisting of a mass of capillaries called gloméruli (glomérulus in the peculiar), encircled with a hollow corm, the capsule of Bowman. The capsule of Bowman brings to a long tubule tangled up in 2 sections: the tubule proximal, the handle of Henle, the tubule distal, and the tube collector. Tubes collectors pour into chalices via papillae, chalices throw themselves into the pelvis, which is linked to the ureter.

Every human kidney counts about a million of néphrons. The number of néphrons is of a big changeability. The number of néphrons is fixed to birth. There is no néphrogenèse at the age adult. The number of néphrons depends on numerous mailmen among which the gestationnel age, the intra-uterine delay of growth, the maternal nutritional state.