Biomaterial Database

Effect of parathyroid hormone on renal tubular permeability. 1976

W B Lorentz

The effect of parathyroid hormone (PTH) on renal tubular permeability has been studied utilizing micropuncture techniques in the rat kidney. After microinjection into superificial nephrons during control conditions, inulin (98.8 +/- 2.7%) and mannitol (97.2 +/- 2.4%) recovery from the experimental kidney was essentially complete. During intravenous infusion of PTH, inulin (99.3 +/- 2.9%) recovery was again complete. Mannitol recovery decreased signficantly after both early-proximal (84.7 +/- 5.8%, P less than 0.001) and late-proximal (89.7 +/- 2.8%, P less than 0.001) injections. There was no loss of either mannitol or inulin following distal tubular injection. Late-proximal TF/P inulin ratios during control conditions were 2.10 +/- 0.20 and decreased insignificantly to 1.99 +/- 0.21 during PTH infusion. Late-proximal TF/P mannitol rations were 2.09 +/- 0.21 during control periods and during PTH infusion decreased significantly to 1.78 +/- 0.19 (P less than 0.001). These results indicate that PTH induces a change in proximal tubular permeability to a usually impermeable nonelectrolyte, mannitol. The effects of PTH on proximal tubular transport could be partially explained by this alteration in permeability, which would increase passive backflux of actively transported species and decrease net transport while having no effect on active transport.

UI	MeSH Term	Description	Entries
D007444	Inulin	A starch found in the tubers and roots of many plants. Since it is hydrolyzable to FRUCTOSE, it is classified as a fructosan. It has been used in physiologic investigation for determination of the rate of glomerular function.
D007684	Kidney Tubules	Long convoluted tubules in the nephrons. They collect filtrate from blood passing through the KIDNEY GLOMERULUS and process this filtrate into URINE. Each renal tubule consists of a BOWMAN CAPSULE; PROXIMAL KIDNEY TUBULE; LOOP OF HENLE; DISTAL KIDNEY TUBULE; and KIDNEY COLLECTING DUCT leading to the central cavity of the kidney (KIDNEY PELVIS) that connects to the URETER.	Kidney Tubule,Tubule, Kidney,Tubules, Kidney
D007686	Kidney Tubules, Distal	The portion of renal tubule that begins from the enlarged segment of the ascending limb of the LOOP OF HENLE. It reenters the KIDNEY CORTEX and forms the convoluted segments of the distal tubule.	Distal Kidney Tubule,Distal Renal Tubule,Distal Kidney Tubules,Distal Renal Tubules,Kidney Tubule, Distal,Renal Tubule, Distal,Renal Tubules, Distal,Tubule, Distal Kidney,Tubule, Distal Renal,Tubules, Distal Kidney,Tubules, Distal Renal
D007687	Kidney Tubules, Proximal	The renal tubule portion that extends from the BOWMAN CAPSULE in the KIDNEY CORTEX into the KIDNEY MEDULLA. The proximal tubule consists of a convoluted proximal segment in the cortex, and a distal straight segment descending into the medulla where it forms the U-shaped LOOP OF HENLE.	Proximal Kidney Tubule,Proximal Renal Tubule,Kidney Tubule, Proximal,Proximal Kidney Tubules,Proximal Renal Tubules,Renal Tubule, Proximal,Renal Tubules, Proximal,Tubule, Proximal Kidney,Tubule, Proximal Renal,Tubules, Proximal Kidney,Tubules, Proximal Renal
D008297	Male		Males
D008353	Mannitol	A diuretic and renal diagnostic aid related to sorbitol. It has little significant energy value as it is largely eliminated from the body before any metabolism can take place. It can be used to treat oliguria associated with kidney failure or other manifestations of inadequate renal function and has been used for determination of glomerular filtration rate. Mannitol is also commonly used as a research tool in cell biological studies, usually to control osmolarity.	(L)-Mannitol,Osmitrol,Osmofundin
D008845	Microinjections	The injection of very small amounts of fluid, often with the aid of a microscope and microsyringes.	Microinjection
D010281	Parathyroid Hormone	A polypeptide hormone (84 amino acid residues) secreted by the PARATHYROID GLANDS which performs the essential role of maintaining intracellular CALCIUM levels in the body. Parathyroid hormone increases intracellular calcium by promoting the release of CALCIUM from BONE, increases the intestinal absorption of calcium, increases the renal tubular reabsorption of calcium, and increases the renal excretion of phosphates.	Natpara,PTH (1-84),PTH(1-34),Parathormone,Parathyrin,Parathyroid Hormone (1-34),Parathyroid Hormone (1-84),Parathyroid Hormone Peptide (1-34),Hormone, Parathyroid
D010539	Permeability	Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.	Permeabilities
D010758	Phosphorus	A non-metal element that has the atomic symbol P, atomic number 15, and atomic weight 31. It is an essential element that takes part in a broad variety of biochemical reactions.	Black Phosphorus,Phosphorus-31,Red Phosphorus,White Phosphorus,Yellow Phosphorus,Phosphorus 31,Phosphorus, Black,Phosphorus, Red,Phosphorus, White,Phosphorus, Yellow