Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0920646 (renal ischemia)
 2,515 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To evaluate the effect of prostaglandin inhibition on the renal blood flow of the ischemic kidney, we administered indomethacin to 10 anesthetized dogs with renal artery stenosis and contralateral nephrectomy. Following the operation to produce renal ischemia, there was an increase of blood pressure associated with an increase of renin and the prostaglandins F1 (PGF1), and E (PGE). The administration of indomethacin to the intact, normotensive animals caused the anticipated decrease of prostaglandin E, renin, and renal blood flow. However, in the hypertensive dogs, indomethacin caused a paradoxical 45 per cent increase in the renal blood flow, despite a 44 per cent decrease of prostaglandin E. PGF1, PGE, renin, and erythropoietin exhibited the anticipated decreased levels. The study suggests that prostaglandins may not be the sole important factor in the regulation of renal blood flow in the presence of ischemia. Other important factors likely include the renin-sensitive angiotensin, the adrenergic, and the kallikrein-kinin systems.
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PMID:Paradoxical increase of renal blood flow in anesthetized hypertensive dog treated with indomethacin. 48

In this randomized, double-blind, placebo-controlled trial the renal function was studied in 60 patients recovering from coronary artery bypass surgery treated with a daily dose of 800 mg sulphinpyrazone (SP) or 880 mg acetylsalicylic acid (ASA) or placebo. Serum creatinine level increased (p less than 0.05) during the first 2 days of SP treatment, but returned to its baseline level within 4 days under maintained therapy; during ASA and placebo therapy no significant changes occurred. Serum urea levels decreased (p less than 0.01) during ASA and placebo treatments as time from surgery subsided; the decrease of serum urea level was delayed in the SP group compared with the ASA and placebo groups. Urinary excretion of prostaglandin E2 (PGE2) was significantly decreased (p less than 0.01) during ASA treatment; in the SP group, urinary PGE2 excretion tended also to decrease during the first days of treatment, the decrease being significant only on the 4th day (p less than 0.01). The urinary excretion of kallikrein decreased significantly only in the SP group (p less than 0.01), while the changes in the ASA and placebo group were not significant. We suggest that the rapidly reversible acute renal impairment during SP therapy was probably due to a transient renal ischemia caused by a drug-related decrease in urinary kallikrein excretion rather than by renal prostaglandin inhibition.
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PMID:Impairment of renal function due to sulphinpyrazone after coronary artery bypass surgery: a prospective double-blind study. 242 79

The high blood flow rate/gram of kidney tissue supplies mainly the renal cortex. The net effect of the interaction of the renin-angiotensin system, the kallikrein-kinin system and prostaglandins is to autoregulate renal blood flow within a narrow range. Drugs and neurogenic factors also influence renal hemodynamics. The renal circulation responds to changes in extracellular fluid volume, and in cardiac output. Renal ischemia occurs readily as these parameters decrease and prompt correction of circulatory dynamics can restore renal blood flow and prevent tubular necrosis. With hypovolemia or heart failure, angiotensin II is a mediator of efferent arteriolar constriction promoting a proportionately greater fall in renal plasma flow than in glomerular filtration rate, thereby augmenting sodium reabsorption. With renal failure, glomerulotubular balance is affected conversely promoting sodium loss. Appreciating these distinctions allows recognition of inappropriate sodium retention or loss. With such data, prognosis can be estimated more accurately and attempts to restore circulatory dynamics can be guided.
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PMID:Pathophysiology of renal hemodynamics. 726 10

The purpose of the present work was to evaluate the kallikrein-kinin system and effects of hypothermia during renal ischemia and reperfusion. Male C57BL/KSJmdb mice were subjected to 20 or 60 min ischemia for different periods of reperfusion. Our results demonstrate that short periods of ischemia followed by reperfusion did not cause significant alterations in kallikrein activity, Evans Blue (EB) extravasation, prokallikreins, myeloperoxidase activity or plasma creatinine concentration. Edema was evident at 1 h reperfusion in the treated mice, but returned to basal values after 24 h reperfusion. Kallikrein activities and EB extravasation showed a significant increase in 60 min ischemic mice. Myeloperoxidase activity in the kidney of the mice confirmed net infiltration in the group with 60 min ischemia and 24 h reperfusion. The generation of kinins and activation of matrix degrading enzymes by tissue kallikrein, liberated from both renal and infiltrated leukocytes, could be responsible at least in part for the damage observed in the kidney of mice subject to 60 min ischemia and reperfusion. The hypothermia significantly reduced the inflammatory process in the 60 min ischemic mice, and did prevent an increase in vascular permeability. Nevertheless, the tissue edema was not shown to change between normothermic and hypothermic ischemic mice.
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PMID:Renal ischemia-induced increase in vascular permeability is limited by hypothermia. 1059 59

We assessed a kallikrein-like amidase activity probably related to the kallikrein-kinin system, as well as the participation of leukocyte infiltration in renal ischemia and reperfusion. Male C57BL/KSJmdb mice were subjected to 20 or 60 min of ischemia and to different periods of reperfusion. A control group consisted of sham-operated mice, under similar conditions, except for ischemia induction. Kallikrein-like amidase activity, Evans blue extravasation and myeloperoxidase activity were measured in kidney homogenates, previously perfused with 0.9% NaCl. Plasma creatinine concentration increased only in the 60-min ischemic group. After 20 min of ischemia and 1 or 24 h of reperfusion, no change in kallikrein-like amidase activity or Evans blue extravasation was observed. In the mice subjected to 20 min of ischemia, edema was evident at 1 h of reperfusion, but kidney water content returned to basal levels after 24 h of reperfusion. In the 60-min ischemic group, kallikrein-like amidase activity and Evans blue extravasation showed a similar significant increase along reperfusion time. Kallikrein-like amidase activity increased from 4 nmol PNA mg protein-1 min-1 in the basal condition to 15 nmol PNA mg protein-1 min-1 at 10 h of reperfusion. For dye extravasation the concentration measured was near 200 microg of Evans blue/g dry tissue in the basal condition and 1750 microg of Evans blue/g dry tissue at 10 h of reperfusion. No variation could be detected in the control group. A significant increase from 5 to 40 units of DeltaAbs 655 nm g wet tissue-1 min-1 in the activity of the enzyme myeloperoxidase was observed in the 60-min ischemic group, when it was evaluated after 24 h of reperfusion. Histological analysis of the kidneys showed migration of polymorphonuclear leukocytes from the vascular bed to the interstitial tissue in the 60-min ischemic group after 24 h of reperfusion. We conclude that the duration of ischemia is critical for the development of damage during reperfusion and that the increase in renal cortex kallikrein-like amidase activity probably released from both the kidney and leukocytes may be responsible, at least in part, for the observed effects, probably through direct induction of increased vascular permeability.
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PMID:Kallikrein-like amidase activity in renal ischemia and reperfusion. 1077 92

To explore the role of the kallikrein-kinin system in relation to ischemia/reperfusion injury in the kidney, we generated mice lacking both the bradykinin B1 and B2 receptor genes (B1RB2R-null, Bdkrb1-/-/Bdkrb2-/-) by deleting the genomic region encoding the two receptors. In 4-month-old mice, blood pressures were not significantly different among B1RB2R-null, B2R-null (Bdkrb2-/-), and WT mice. After 30 min of bilateral renal artery occlusion and 24 h of reperfusion, mortality rates, renal histological and functional changes, 8-hydroxy-2'-deoxyguanosine levels in total DNA, mtDNA deletions, and the number of TUNEL-positive cells in the kidneys increased progressively in the following order (from lowest to highest): WT, B2R-null, and B1RB2R-null mice. Increases in mRNA levels of TGF-beta1, connective tissue growth factor, and endothelin-1 after ischemia/reperfusion injury were also exaggerated in the same order (from lowest to highest): WT, B2R-null, and B1RB2R-null. Thus, both the B1 and B2 bradykinin receptors play an important role in reducing DNA damage, apoptosis, morphological and functional kidney changes, and mortality during renal ischemia/reperfusion injury.
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PMID:Bradykinin B1 and B2 receptors both have protective roles in renal ischemia/reperfusion injury. 1745 47