Vein, renal

More specific laboratory tests are used to diagnose secondary hypertension. These include plasma norepinephrine and urinary metanephrine levels for pheochromocytoma, plasma and urinary aldosterone levels for primary aldosteronism, and plasma renin activity, captopril stimulation test, renal vein renins, and renal artery angiography for renovascular disease. 

Blood is supplied to the kidneys via the renal vein, a branch of the descending vena cava, at relatively high pressure to ensure rapid filtration of plasma across the membranes of the blood vessels in the glomeruli and the epithelial cells of the Bowman s capsule. The net filtration pressure of about 5-6 kPa, is the difference between the blood pressure forcing plasma water across the filtration barrier and the opposing osmotic and... 

Another study of the effects of I on the cardiovascular systemic concluded that, in dogs anesthetized with sodium pentobarbital, the response of blood pressure to intravenous administration of I is a resultant of two separate effects a direct myocardial stimulation that was stopped with dichlorolsoproterenol and a stimulation of vascular smooth muscle that results in a slight increase in renal arterial pressure and a slight decrease in renal arterial flow. Neither atropine nor dichlorolsoproterenol affected these vascular effects. Injections of 1 into a jugular vein or a renal artery had no consistent effect on catecholamine concentrations in plasma taken from a femoral artery or a renal vein. In seven experiments in which I at 21-35 mg/kg was injected into a jugular vein, the mean blood pressure increased from 176/125 + 22/11... 

Whatever the site of the enzyme may be, Keston et al. have recently produced fairly conclusive evidence that glucose, which is reabsorbed by the kidney, is exposed to mutarotase at some stage of the process (117). Glucose infused into the renal artery spills into urine when the renal threshold is exceeded in the same anomeric form as that administered, whereas reabsorbed glucose in the renal vein is mutarotated. Hill has also shown that the anomer infused in excess is excreted in excess (73). 

Bohler J, Hauenstein KH, Hasler K, Schollmeyer P. Renal vein thrombosis in a dehydrated patient on an oral contraceptive agent. Nephrol Dial Transplant 1989 4(ll) 993-5. 

Under the proper stimulus renin is released into the circulating blood where it can be identified, especially in that from the renal vein. It acts rapidly upon its specific substrate, splitting the protein into peptides, one or more of which have been called hypertensin or angiotonin. Hypertensin has been concentrated but not obtained in pure form. It is the effector substance of renin, constricting arterioles and raising blood pressure. The action of hypertensin is abolished by hypertensinase, an enzyme found in blood and renal extracts. Fortunately, the latter is destroyed by heat and alkalinity. 

Maruyama, H., Higuchi, N., Nishikawa, Y., Hirahara, H., lino, N., Kameda, S., Kawachi, H., Yaoita, E., Gejyo, F. and Miyazaki, J. (2002). Kidney-targeted naked DNA transfer by retrograde renal vein injection in rats. Hum. Gene Ther. 13, 455-468. 

Twenty-five percent ofthrombophilic patients develop thrombosis at unusual sites resulting in cerebral venous thrombosis, mesenteric vein thrombosis, hepatic venous thrombosis, retinal vein thrombosis, purpura fulminans, splenic vein thrombosis, portal vein thrombosis, renal vein thrombosis, or axillary vein thrombosis. The thrombotic disorders may involve inflammatory factors that contribute to the vascular deficit. In addition, embolic events also play a role in the development of these thrombotic complications. 

Hepatic venous thrombosis, also known as Budd-Chiari syndrome, is caused by hypercoagulable disorders precipitated by pregnancy, infection, and birth control medication. An acute painful abdomen, sudden enlargement of the liver, and the presence of ascites make up a triad of clinical symptoms that are important in the diagnosis of this syndrome. Myeloproliferative disorders such as polycythemia vera and paroxysmal nocturnal dyspnea were previously thought to be responsible. Factor V Leiden and prothrombin 20210 mutations are also known to be responsible, Other intraabdominal thromboses include portal vein thrombosis, mesenteric vein thrombosis and renal vein thrombosis. 

Each kidney receives its blood supply from a renal artery, two of which branch from the abdominal aorta. Upon entering the hilum of the kidney, the renal artery divides into smaller arteries which in turn give off still smaller branches. Branching off these are the afferent arterioles supplying the glomerular capillaries, which drain into efferent arterioles. Efferent arterioles divide into peritubular capillaries that provide an extensive blood supply to the renal cortex. Blood from these capillaries collects in renal venules and leaves the kidney via the renal vein. Blood supply is intimately linked to blood pressure. 

In about 5% of cases, blood passes through the short gastric veins to the splenic vein and then through other collateral veins to the left renal vein (= spontaneous splenorenal shunt). 

Distally, the suprarenal veins and Retzius veins provide a pathway into the inferior vena cava via the renal vein. The Retzius veins act as anastomoses between the portal vein branches in the intestinal and mesenteric regions and the branches of the inferior vena cava. (57)... 

Hypokalaemia Hypokalaemia increases the activity of renal glutaminase, so that more ammonia is formed and transported back via the blood of the renal vein. A lack of potassium in the brain cells is in itself a further cause of serious cerebral dysfunction, (s. fig. 15.2)... 

Eppel GA, Osicka TM, Pratt LM, Jablonski P, Howden BO, Glasgow EE, Comper WD The return of glomerular-filtered albumin to the rat renal vein. Kidney Int 55 1861-70,1999... 

Zoghby Z, Sekhon IS, Miller DV, Sethi S. Cocaine, loin pain, and renal vein thrombosis. Am J Kidney Dis. 2007 49(6) 859-861. 

Figure 47-1 i The portal-venous system. HY, Hepatic vein IVC, inferior vena cava IMV, inferior mesenteric vein LGV, left gastric vein LRV, left renal vein PV, porta vein RRV, right renal vein ... 

BOX 51-14 Protocol for the DifTerential Renal Vein Renin Test... 

Rationale In renovascular hypertension, PRA is higher in the renal vein on the involved side. 

Procedure The patient should be on a low-sodium, high-potassium diet and receiving a diuretic for 3 days before the procedure. Under fluoroscopic guidance, percutaneous catheterization is performed, and blood samples are obtained from both renal veins and the inferior vena cava for determination of PRA. 

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