Biomaterial Database

Calcium and magnesium transport along the inner medullary collecting duct of the rat. 1980

H H Bengele, and E A Alexander, and C P Lechene

We have measured calcium and magnesium transport along the inner medullary collecting duct (IMCD) in rats by the microcatheterization technique. The fraction of filtered divalent cation ((F/P)Ca,Mg/In) as a function of IMCD length was analyzed by linear regression. In eight control rats calcium reabsorption was demonstrated, inasmuch as there was a significant correlation and slope, P less than 0.001. (F/P)Ca/In decreased from 2.2 +/- 0.3% at the beginning of the IMCD to 0,84 +/- 0.1% in the urine. (F/P)Mg/In was not changed along the IMCD, After acute thyroparathyroidectomy (TPTX) (F/P)Ca/In increased to 4.6 +/- 0.4% at the beginning of the IMCD and 1.55 +/- 0.1% in the urine. The slope was not significantly different from the control group. (F/P)Mg/In was unchanged and was not different from the control group. Accordingly, net Ca reabsorption occurs along the IMCD and the fractional Ca reabsorption is not altered by TPTX. Net Mg transport along the IMCD was absent in both control and TPTX rats; The increased calciuresis after TPTX is not dependent on IMCD function nor is Mg excretion under the conditions studied.

UI	MeSH Term	Description	Entries
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
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
D007685	Kidney Tubules, Collecting	Straight tubes commencing in the radiate part of the kidney cortex where they receive the curved ends of the distal convoluted tubules. In the medulla the collecting tubules of each pyramid converge to join a central tube (duct of Bellini) which opens on the summit of the papilla.	Kidney Collecting Ducts,Kidney Collecting Duct,Collecting Duct, Kidney,Collecting Ducts, Kidney
D008274	Magnesium	A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
D008297	Male		Males
D010280	Parathyroid Glands	Two pairs of small oval-shaped glands located in the front and the base of the NECK and adjacent to the two lobes of THYROID GLAND. They secrete PARATHYROID HORMONE that regulates the balance of CALCIUM; PHOSPHORUS; and MAGNESIUM in the body.	Gland, Parathyroid,Glands, Parathyroid,Parathyroid Gland
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
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002408	Catheters, Indwelling	Catheters designed to be left within an organ or passage for an extended period of time.	Implantable Catheters,In-Dwelling Catheters,Catheter, In-Dwelling,Catheter, Indwelling,Catheters, In-Dwelling,In Dwelling Catheters,In-Dwelling Catheter,Indwelling Catheter,Indwelling Catheters
D005919	Glomerular Filtration Rate	The volume of water filtered out of plasma through glomerular capillary walls into Bowman's capsules per unit of time. It is considered to be equivalent to INULIN clearance.	Filtration Rate, Glomerular,Filtration Rates, Glomerular,Glomerular Filtration Rates,Rate, Glomerular Filtration,Rates, Glomerular Filtration