Endocrine impacts on kidney function

What is diabetes Mellitis

When there is high blood glucose, so an increase in osmotic diuresis, increases urination

Diabetes insipidus

increase in urine, ieither kidneys do not respond to any hormone, or the brain may have a tumour preventing the hypothalamus from producing any hormones…

What is central neurogenic diabetes insipidus

failure to prevent diuresis as no ADH

diueresis vs polydiuresis

diuresis = excessive urine production…

polydiuresis = over production of urine ~(in excessive amounts)

What is CENTRAL diabetes insipidus

failure to prevent diuresis (no ADH)

What is secondary nephrogenic diabetes insipidus..

ADH present, B~U~T action = inhibited. E>G> cortisol.. Excessive urination as no water is being absorbed back into the blood…

What 3 endocrine hormones does the kidney secrete..

• Renin - poor renal blood flow, promotes circulation

• Erythropoietin - renal hypoxia encourages RBC

• Vitamin D (calcitrol) - conversion in kidney, Ca + P storage/ release..

What do the kidneys do (basically)

filtration, selective reabsorption, secretion

What is the key component of a kidney

Nephrons. Functionally competent and gradually drop off with age.. Many die as going. 20% cardiac output, glomerulus filters a filtrated out which then becomes filtered..

At what point can you see a rediced renal kidney fucntion

when there is 70% nephron loss (something excreted that would normally be reabsorped)

where does ultrafiltration occour…

glomerulus and the bowmans capsule..Filtratoin = under pressure due to narrow efferenet artereole.. depends on molecules waste proteins do not get through. Can caclulate the Glomerular Filtratoin rate..

Where does most reabsorption occour..

Proximal convoluted tubule.. Epithelial cells have microvilli at the luminal surface and many mitrochondria

What 3 things are removed in ultra filtrate

• nitrogenous waste, ureas, phosphorous, potassium (elecrotlytes so that the balance is not damaged…)

How is waster conserved in the kidney

At the loop of hennle.. medullary concentration gradient… vascular network urea trapped + collecting duct… ADH allows reabsorption. High hormone influence… ?Colllecting ducts = final stage of water reabsorption..

What is glucosuria

• blood glucose concentration above 14mmol/ l (obesity induced may be
  ) + may attract pathogens

• If too high, glucose cannot be reabsorped as too much, as there is glucose then water will move into it, therefore diuresis as increased water content in the urine

Azotaemia…

• Increase urea or creatine

• Pre renal azotaemia (not enough blood filtered) LAck of nephrons (renal disease)

Diabetes Insipidus

• ADH not being made/ action is blocked

• therefore no water reabsorptoin..

• Inspection, no ADH..

What is USG

Urine specific gravity, measure the how many osmotic particles are in theurine.. may bbe more or less concentrated urine… think CKD can confirm renal disease

What is the average USG in a cat

1.040

What is the average USG in a dog

1.030

What is a key sign of polyuria

polydipsia

How does glomerular filtrate occour

• everything passes outinto the filtrate

• PCT reabsorps all useful stuff

• loop of Henle concentrates tissue fluid

• OSmosisc diltrate. ADH, NA and water..

SUmmary of kidney hormones..

adh - water

alderosterone - Na pump (therefore osmosis so pressure)

Parathyroid - calcium phosphate.. increase ca from bone, increasae renal uptake.. cholecalciferol..S

secondary renal hypoparathyroidism, not getting ri dof phosphate, this then activates pth due to the imbalance..

Hypoadrenocorticism

• lack of aldosterone

• adrenal cortex at production site

• Na not reabsorbed and K not excreted..

Hyperphosphataemia

-CKD, phosphorous retendion. parathyroid gland responds, secondary hyperparathyroidism..

excessive pth production, renal calcium retention + phosphate loss.. hyperthroudism is increased renal flow rate..