• Korean Journal of Veterinary Research
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• v.41 no.3
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• pp.299-304
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• 2001

The effect of the nitric oxide synthase(NOS) inhibitor, $N^{G}$-nitro-L-arginine methyl ester (L-NAME), and the prostanoid synthesis inhibitor, indomethacin, on the vasodilatation produced in response to acetylcholine(Ach) on the isolated rabbit renal artery was examined. The vasodilatory reponses to Ach($10^{-8}-3{\times}10^{-5}M$) were completely absent in thevessel which the endothelium had previous been removed. L-NAME($10^{-4}M$) significantly reduced the vasodilatory reponse to the Ach($10^{-8}-3{\times}10^{-5}M$). When L-arginine ($10^{-3}M$) was also present in the organ bath along with L-NAME($10^{-4}M$), this inhibitory effect of L-NAME ($10^{-4}M$) on the vasodilatory response to Ach ($10^{-8}-3{\times}10^{-5}M$) was significantly attenuated, Indomethacin ($10^{-6}M$) did not significantly affect the vasodilatory responses to Ach ($10^{-8}-3{\times}10^{-5}M$). The inhibition by L-NAME ($10^{-4}M$) and indomethacin ($10^{-6}M$) on vasodilatory response to Ach was significantly greater than the inhibition due to L-NAME ($10^{-4}M$) alone. The present study has established that Ach induce relaxation via and endothelium-dependent mechanism, this relaxation to Ach involves both nitric oxide(NO) and prostanoid in the isolated rabbit renal artery.

• The Korean Journal of Physiology
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• v.24 no.1
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• pp.161-170
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• 1990

The effects of $H^{+}$ on the arterial contraction and their mechanisms were investigated in the renal artery of a rabbit. The helical strips of isolated renal artery were immersed in the HEPES-buffered or $CO_{2}/HCO_{3}^{-}$-buffered Tyrode's solution. The contractions induced by agonists (norepinephrine, histamine, serotonin and angiotensin II) or high $K^{+}$ were observed with change of extracellular or intracellular $H^{+}$ concentration. The contractions induced by norepinephrine, histamine, serotonin, angiotensin II or high $K^{+}$ in HEPES-buffered Tyrode's solution were inhibited by increase in extracellular $H^{+}$ concentration and potentiated by decrease in extracellular $H^{+}$ concentration. The degrees of these effects were most evident in the contraction induced by serotonin and angiotensin II, moderate in those by histamine and high $K^{+}$, and least in those by norepinephrine. Maximal contraction by norepinephrine, histamine and high $K^{+}$ were not influenced by change in extracellular $H^{+}$ concentration, but influenced in those contration by serotonin and angiotensin II. The attenuated contractions by an acidic pH were not returned to the level of contraction at normal pH (7.4) by elevation of extracellular $Ca{2+}$ concentration. The agonists (norepinephrine, histamine and serotonin)-induced contractions in $Ca{2+}$-free Tyrode's solution were also attenuated by increase in extracellular $H^{+}$ concentration and potentiated by decrease in extracellular $H^{+}$ concentration. Elevation of $Pco_{2}$ in the $CO_{2}/HCO_{3}^{-}$-buffered Tyrode's solution, which increase the intracellular $H^{+}$ concentration, at constant extracellular pH (7.4), increased the contraction by 30 mM $K^{+}$. From the above results, it is suggested that the decrease in contractions by increase in extracellular $H^{+}$ concentration may be resulted from that $H^{+}$ make the receptors less sensitive to agonists and cell membrane hyperpolarize and then inhibit the $Ca{2+}$ influx as well as $Ca{2+}$ release from intracellular $Ca{2+}$ storage site.

• The Korean Journal of Physiology
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• v.24 no.2
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• pp.293-303
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• 1990

The contractile action of barium $(Ba^{2+})$ was investigated in the arterial strip of rabbit renal artery. The helical strip of isolated renal artery was immersed in the Tris-buffered Tyrode's solution equilibrated with 100% $O_2$ at $37^{\circ}C$ and its isometric tension was measured. $Ba^{2+}-induced$ contraction of arterial strip was dose-dependent and its maximal tension corresponded to $92.1{\pm}4.5%$ of tension by $K^+(100\;mM)$. $Ba^{2+}-induced$ contraction did not show the tachyphylactic phenomenon in the normal Tyrode's solution. $Ba^{2+}$ induced the tonic contraction in the $Ca^{2+}-free$ tyrode's solution and that was increased by the extracellula addition of $Ca^{2+}$. During the repeated exposure of the same dose of $Ba^{2+}\;(10\;mM)$ in the $Ca^{2+}-free$ Tyrode's solution, $Ba^{2+}-induced$ contraction was progressively decreased. Even though the intracellular NE-and caffeine-sensitive $Ca^{2+}$ was depleted, $Ba^{2+}$ induced the tonic contraction. After the pretreatment of lanthnum or verapamil, $Ba^{2+}$ did not induce contraction. $Ba^{2+}-induced$contraction was suppressed by extracellular $K^+$ in the normal Tyrode's solution and that was dependent on $K^+$ concentration. Suppressive effect of $K^+\;(14\;mM)$ on the $Ba^{2+}-induced$ contraction was also dependent on the intracellular $Ca^{2+}$ concentration. From the above resuts, it is suggested that $Ba^{2+}$ activate indirectly the contractile process by promoting the mobilization of intracellular $Ca^{2+}$ and the influx of extracellular $Ca^{2+}$. It is also suggested that action of $Ba^{2+}$ on the $Ca^{2+}-activated$ $K^+$ channel can result in the depolarization of cell membrane in the rabbit renal artery.

• The Korean Journal of Pharmacology
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• v.25 no.1
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• pp.43-51
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• 1989

Responsiveness of muscarinic and alpha adrenoceptor activation on endothelial cells was studied in isolated canine renal artery rings. Ach (10-100 nM), dose dependently, relaxes endothelial intact rings precontracted with phenylephrine ($IC_{50}$ of Ach was 34.5 nM). Selective mechanical destruction of the endothelium transformed the activity of this substance from vasodilatation to vasoconstriction. Acetylcholine induced relaxations could be selectively inhibited competitively by atropine, but could not be inhibited by cyclooxygenase inhibitor. Methylene blue, however, an inhibitor of soluble guanylate cyclase activity, inhibited Ach as well as sodium nitroprusside (SNP) induced relaxation. Relaxation produced by prostacyclin was not modified by methylene blue. On the other hand, alpha adrenoceptor agonist did not relax but contract canine renal artery rings possessing an intact intima precontracted with U-46619. Clonidine, however, selective alpha-2 adrenergic agonist, is more susceptible than phenylepherine, selective alpha-1 adrenergic agonist, to the inhibitory effect of contraction. These results suggest that in canine renal artery rings, 1) muscarinic receptor is responsible for releasing endothelium dependent relaxation factor (EDRF). 2) alpha-1 and alpha-2 adrenergic receptors are present in canine renal artery. 3) relaxation via EDRF is antagonized by methylene blue, providing further evidence that EDRF acts through a cGMP mechanism.

• Journal of Chest Surgery
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• v.27 no.1
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• pp.48-51
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• 1994

Doing CABG in patient with renal transplantation requires special concern to keep and preserve renal function safely during and after operation. We experienced two cases of CABG for treatment of myocardial ischemia. who underwent renal transplantation 2 and 3 years ago respectively. The first patient received single reversed saphenous vein graft at LAD and second one received double saphenous vein graft at LAD and OMI. Peri & postoperative urinary volume and renal function test were comparable with preoperative status in both cases. Although abnormal lipid metabolism due to long term use of immunosuppressive regimen act a causative role in development and progression of coronary artherosclerosis in renal transplantation patient, CABG can be done safely with some precaution including maintenance of adequate mean blood pressure and blood level of immunosupressive regimen during cardiopulmonary bypass.

• Journal of Chest Surgery
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• v.31 no.4
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• pp.402-408
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• 1998

A 56-year old female underwent total aortic arch replacement March 1995, because of an expanding chronic Debakey type I aortic dissection. This aortic dissection had an intimal tear at the origin of the right carotid artery. Retrograde and antegrade propagation of dissection resulted in aortic arch blood flow separation and expanding pseudolumen to the abdominal aorta. Sudden anuria(ARF) developed 3 hours later postoperatively and renal doppler ultrasonography and aortography showed diminished blood flow of renal arteries. We performed balloon aortic dilatation but failed. She could be restored good renal flow after intimal flap fenestration resection and thrombectomy of the abdominal aorta. This patient could be discharged in a state of mild CRF after 2 months of ICU care for respiratory and renal failure.

• Journal of Trauma and Injury
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• v.23 no.1
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• pp.16-20
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• 2010

Purpose: High-grade (III, IV, V) renal injury may need interventional management. We investigated whether the selective embolization of the renal artery is effective for the treatment of major renal injury in comparison with emergency renal exploration. Methods: We retrospectively reviewed the medical and radiologic records of patients who underwent surgery or embolization for renal injury (Grade III, IV, V) between January 1990 and December 2007. We analyzed the change in treatment method before and after 2000, the blood pressure, the hemoglobin at the time of visit, the hospital days and the complications in patients who received surgery or embolization. Preserved renal functions of the embolized kidneys were identified by using enhanced CT. Results: Cases of surgery and embolization were 37 and 13, respectively: 5 and 4 in renal injury grade III, 17 and 6 in grade IV and 13 and 3 in grade V. Cases of surgery and embolization were 33 and 1 before 2000 and 2 and 12 after 2000, repectively: embolizations increased after 2000. No significant differences in mean diastolic pressure, hemoglobin, hospital days and complications existed between the surgery and the embolization groups (p>0.05). However, the transfusion volume was significantly smaller in the embolization group (p<0.05). One postoperative complication occurred in the surgery group. We identified the preserved renal functions of the embolized kidney by using enhanced CT. Conclusion: Embolization could be one treatment method for high-grade renal injury. Thus, we might suggest selective embolization a useful method for preserving the renal function in cases of high-grade renal injury.

• Clinical and Experimental Pediatrics
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• v.60 no.8
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• pp.266-271
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• 2017

Purpose: The aim of this study was to assess the clinical characteristics of hypertensive encephalopathy according to the underlying etiologies in children. Methods: We retrospectively evaluated 33 pediatric patients who were diagnosed as having hypertensive encephalopathy in Chonbuk National University Children's Hospital. Among the patients, 18 were excluded because of incomplete data or because brain magnetic resonance imaging (MRI) was not performed. Finally, 17 patients were enrolled and divided into a renal-origin hypertension group and a non-renal-origin hypertension group according to the underlying cause. We compared the clinical features and brain MRI findings between the 2 groups. Results: The renal group included renal artery stenosis (4), acute poststreptococcal glomerulonephritis (2), lupus nephritis (2), and acute renal failure (1); the nonrenal group included essential hypertension (4), pheochromocytoma (2), thyrotoxicosis (1), and acute promyelocytic leukemia (1). The mean systolic blood pressure of the renal group ($172.5{\pm}36.9mmHg$) was higher than that of the nonrenal group ($137.1{\pm}11.1mmHg$, P<0.05). Seizure was the most common neurologic symptom, especially in the renal group (P<0.05). Posterior reversible encephalopathy syndrome (PRES), which is the most typical finding of hypertensive encephalopathy, was found predominantly in the renal group as compared with the nonrenal group (66.6% vs. 12.5%, P<0.05). Conclusion: We conclude that the patients with renal-origin hypertension had a more severe clinical course than those with non-renal-origin hypertension. Furthermore, the renal-origin group was highly associated with PRES on brain MRI.

• The Korean Journal of Physiology
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• v.25 no.2
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• pp.171-177
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• 1991

This study was carried out to determine effect of acute renal ischemia on transport function of organic cation, tetraethylammonium (TEA), in rabbit kidney proximal tubule. Clamping of the renal artery for 30 and 60 min produced a polyuria which was accompanied by an increase in $Na^+$ excretion. The capacity of kidney cortical slices to accumulate TEA was increased after 30 and 60 min of ischemia. When blood flow was restored for 30 min after 30 and 60 min of ischemia, the augmented TEA uptake was recovered to the control values. Oxygen consumption of cortical slices was stimulated after 30 min of ischemia, whereas it was not altered by 60 min of ischemia. A 90-min ischemia produced a significant inhibition of TEA uptake and tissue oxygen consumption. These results suggest that the basolateral transport system for organic cation persists after ischemic periods of 60 min despite evidence that tubular reabsorptive mechanism of $Na^+$ and water is markedly impaired. This may indicate that the active secretory systems of proximal tubule are more resistant to ischemic injury than the reabsorptive systems.

• Journal of Chest Surgery
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• v.23 no.3
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• pp.482-487
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• 1990

The leading cause of death in patients with chronic renal failure is cardiovascular diseases. The problems relevant to cardiac surgery in these patients are occurring more frequently with a growing number of patients at risk. Among these, important risk factors related to uremic patients undergone open heart surgery are fluid and electrolytes imbalance, coagulopathy, increased susceptibility to infection. Since 1968 when Lansing and colleagues reported the first successful aortic valve replacement in patients with chronic renal failure and infective endocarditis, there have been increasing reports of the cardiopulmonary bypass surgery in chronic renal failure patients with acceptable perioperative morbidity and mortality From Jan. 1988 to Nov. 1989 we have experienced four uremic patients necessitating open heart surgery ; one needing a coronary artery bypass graft and the other 3 needed cardiac valve replacement. Based on our observations we would like to suggest followings 1]Intraoperative ultrahemofiltration during C-P bypass thought to be an excellent means for the control of hyperkalemia and fluid balance. 2] The immediate postoperative application of peritoneal dialysis instead of hemodialysis is beneficial in controlling fluid and electrolyte imbalance. 3]The cause of one early postoperative death was not associated to renal failure, rather it was the result of an accidental rupture in the right ventricular wall.