kidneys


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Related to kidneys: Polycystic kidneys

Kidneys

A pair of organs located on each side of the spine in the lower back area. They excrete, or get rid of, urine.
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kidneys

paired organs in the back of the abdomen. By filtration of water and small molecules from the blood flowing through the capillary complex of their glomeruli, they extract about 1/5 of the whole blood volume per minute, for passage into the tubules where, by selective reabsorption back into the blood, the quantity and content of the urine are regulated. By these means, under the influence of hormones they excrete waste substances and regulate electrolyte and acid-base balance, as well as blood volume, and the concentration of various substances in the blood. They also secrete renin and renal erythropoietic factor and are involved in vitamin D metabolism. See also Table 1.
Table 1: Hormones
Site of productionName of hormoneMain targetsInvolved in regulating:Secretion controlled by:
HypothalamusReleasing and inhibiting hormonesAnterior pituitary (via local blood vessels)Secretion of anterior pituitary hormonesOther brain regions; feedback re regulated hormones and their actions
Neurohormones released from posterior pituitary:
OxytocinUterus, breastsLabour and lactationAfferent information from target organs
Antidiuretic hormone (ADH, vasopressin)KidneysWater loss: ECF volume and osmolalityHypothalamic osmoreceptors
Anterior pituitary(Human) growth hormone (H)GHMost cellsGrowth and metabolismHypothalamic releasing and inhibiting hormones via local blood vessels
ProlactinBreastsMilk production
Trophic hormones:
Thyroid-stimulating (TSH)Thyroid glandThyroid secretions
GonadotrophinsOvary or testisGerm cell maturation and hormone secretions
Adrenocorticotrophic (ACTH)Adrenal cortexCortisol secretion
Pineal bodyMelatoninWidespread, including brain, thymus, etc.
  • Sleep/wake cycle
  • Antioxidant
  • Immune system
Hypothalamus; varying light input from retina
Thyroid
  • Thyroxine
  • Triiodothyronine
  • Calcitonin
  • Most cells
  • Bone, kidneys, gut
  • Cellular oxidative metabolism
  • Decreases ECF [Ca2+]
  • TSH from anterior pituitary. Negative feedback from blood hormone concentration
  • ECF [Ca2+]
ParathyroidsParathormoneBone, kidneys, gut
  • Calcium and phosphorus absorption, secretion and turnover in bone.
  • Increases ECF [Ca2+]
ECF [Ca2+]
Adrenal: Cortex
  • Cortisol
  • Aldosterone
  • Androgens
  • Most cells
  • Kidneys
  • Gonads & other tissues
  • Metabolism
  • Response to stress
  • Na and K balance
  • Sex characteristics and reproductive function
  • ACTH from anterior pituitary
  • ECF [Na+] [K+]
  • Renin-angiotensin
  • ACTH
Medulla
  • Adrenaline
  • Noradrenaline
Heart, smooth muscle, glandsCardiovascular and metabolic adjustments to activity and stressSympathetic nervous system
Atrial wallAtrial natriuretic hormoneKidneysBlood volume; increases sodium (therefore also water) loss in urineStretch of atrial wall by venous pressure
Gonads: TestisAndrogens (mainly testosterone)Genitalia and other tissuesReproductive function and sex characteristicsAnterior pituitary gonadotrophins
Ovary
  • Oestrogens
  • Progesterone
Uterus, breasts and other tissuesMenstrual cycle, pregnancy, lactation
Pancreas
  • Insulin, glucagon
  • Somatostatin
  • Most cells
  • Other secretory cells in the pancreas
Blood levels, storage and cellular uptake of nutrients, notably glucose, but also proteins and fatsBlood levels of nutrients; autonomic nervous system; other gastrointesinal hormones
Alimentary tract
StomachGastrinGastric acid-secreting cellsGastrointestinal functions: motility, digestive juices and other secretionsLocal chemical and mechanical factors in the alimentary tract
Small intestine
  • Secretin
  • Cholecystokinin- pancreozymin (CCK-PZ)
  • Somatostatin, motilin
  • Other peptide hormones including vasoactive intestinal peptide (VIP)
  • Widespread on
  • GI tract
Several GI functions including bile flow, pancreatic enzyme and exocrine secretionsIngestion of food, distension of GI tract

Patient discussion about kidneys

Q. Why do i get kidney stones? I am 38 and have had three stones pass so far. Is it the coffee, the meat, the stress, or the damned DNA?! My uncle is in his 50s and has passed over 30 stones!

A. Kidney stones are very common and even without the genetic or familial background people tend to get them. Of course, the more family predisposition you have, the higher are your chances of developing them, which is probably why you did. Also, a diet rich with dairy and calcium can cause your body to store excess calcium, that tends to calcify and create stones. Not drinking enough fluid is also one of the reasons.

Q. How can i overcome kidney ache? in the morning it appears.after wake up.

A. First of all, it is important to distinguish kidney ache from lower back ache. If you have ever suffered from kidney problems or infections, it might be advisable to see a doctor, and rule out an infection. However, if you are otherwise healthy, and have been experiencing back pain after you wake up, it is very much possible your pain is not from the kidneys, but from the muscles of your back. In this case, some exercise on a daily basis to help strengthen your lower back can very much ease the pain you're experiencing.

Q. what cause pain around kidney uncomfortable pressure swelling right side back

A. thanx....the pain is dull and there's no fever: muscular pain perhaps? If it worsens, persists or fever developes; I will head to the Doctor. thamx again....

More discussions about kidneys
References in periodicals archive ?
TheNational Kidney Foundation is the leading organization in the U.
It provides a perfect opportunity to get out in the community and share the World Kidney Day message with public.
But previous research suggests that HIV-positive people who start combination antiretroviral therapy maintain healthy kidneys better than HIV-positive people not taking antiretrovirals.
The cells also produced proteins essential for kidney function, grew into structures that resembled the filtration units in mammal kidneys and even made small amounts of urine.
She advises taking simple steps to help to avoid high blood pressure and reduce the risk to the kidneys.
When she received a new kidney via transplant, Altadena teen Ishrat Khan quickly set herself a modest but attainable goal.
May Commercial Real Estate, had a crucial kidney transplant operation in December 2003.
Urine exits the kidneys through two thin tubes about eight to 10 inches long called ureters, which carry the fluid to the bladder, a hollow muscular organ that stores urine.
When the kidneys fail, fluids accumulate, and blood pressure increases.
Only about 15 percent of kidney transplants are done with living donors, the other recipients must wait about five years before receiving a kidney from a nonliving donor.
Expanded criteria donor (ECD) kidneys accounted for 21% of all recovered kidneys during the first year after the change and 16% of all transplants, according to Ms.
Many studies have reported impaired renal function and kidney disease at high levels of lead exposure, as estimated mainly through concentrations of serum creatinine (SCr) and rates of creatinine clearance from the body.