Renal physiology最新文献_第3页

Renovascular effects of adenosine receptor agonists. 腺苷受体激动剂对肾血管的影响。

Renal physiology Pub Date : 1987-01-01 DOI: 10.1159/000173135

F G Holz, M Steinhausen

{"title":"Renovascular effects of adenosine receptor agonists.","authors":"F G Holz, M Steinhausen","doi":"10.1159/000173135","DOIUrl":"https://doi.org/10.1159/000173135","url":null,"abstract":"The purpose of the present experiments was to determine the renovascular effects of the adenosine agonists N-ethyl-carboxamide adenosine (NECA), N6-cyclohexyl adenosine (CHA) and 2-chloro adenosine (2-CLA). The diameter of pre- and postglomerular vessels in the split hydronephrotic kidney of Inactin-anesthetized rats was measured by in vivo television microscopy. All metabolically stable adenosine agonists were topically applied into the renal tissue bath. NECA, a preferential A2 adenosine receptor agonist, induced dose-dependent marked pre- and slight postglomerular vasodilation except for a small constrictory effect on the afferent arteriole near the glomerulus. Application of CHA, a selective A1 adenosine receptor agonist, led to a vasoconstriction of all preglomerular vessels, the extent of which was greatest at the most distal segment of the afferent arteriole. 2-CLA, a nonselective agonist, produced a small decrease in diameter in all preglomerular vessels, a marked constriction of the afferent arteriole at sites near the glomerulus, and a slight dilation of postglomerular vessels. Glomerular blood flow (GBF) was increased by NECA, and decreased by CHA and 2-CLA. The effects of CHA in reducing GBF were greater than those of 2-CLA. From these experiments it is concluded that vascular A1 and A2 adenosine receptors are present in the kidney and that activation of A1 receptors is associated with preglomerular vasoconstriction only, whereas activation of A2 receptors mediates pre- and postglomerular vasodilation with a lack of vasodilatory response of the distal afferent arteriole. Furthermore, these data indicate that nonselective occupation of both receptor subclasses is associated with marked vasoconstriction of the afferent arteriole and little vasodilation of the efferent arteriole.","PeriodicalId":77779,"journal":{"name":"Renal physiology","volume":"10 5","pages":"272-82"},"PeriodicalIF":0.0,"publicationDate":"1987-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000173135","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14579956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 75

Renal and renin effects of sodium thiopental in rabbits. 硫喷妥钠对家兔肾脏和肾素的影响。

Renal physiology Pub Date : 1987-01-01 DOI: 10.1159/000173134

K W Cho, S H Kim, G Y Koh, K H Seul, H J Kim, H S Song

{"title":"Renal and renin effects of sodium thiopental in rabbits.","authors":"K W Cho, S H Kim, G Y Koh, K H Seul, H J Kim, H S Song","doi":"10.1159/000173134","DOIUrl":"https://doi.org/10.1159/000173134","url":null,"abstract":"Unilateral renal arterial infusion of sodium thiopental on renal function and renin secretion were investigated in unanesthetized rabbits. Sodium thiopental infusion in doses of less than 0.3 mg/kg/min into unilateral renal artery caused dose-dependent increases in urine flow, urinary excretion of electrolytes, fractional excretion of sodium and free water clearance with no changes in systemic blood pressure and clearance of p-aminohippuric acid (renal blood flow). An anesthetic dose of sodium thiopental administered intravenously caused decreases in systemic blood pressure, renal hemodynamics, urine flow and free water clearance during the early period of anesthesia followed by increases in urinary excretion of sodium and fractional excretion of sodium. Unilateral renal arterial infusion of sodium thiopental decreased the renin secretion rate and plasma norepinephrine concentration in renal vein, whereas an anesthetic dose of sodium thiopental administered intravenously increased the renin secretion rate. These observations suggest that the diuretic, natriuretic and renin suppressive effects of sodium thiopental may be due to an inhibition of intrarenal sympathetic nervous system or due to a direct tubular action.","PeriodicalId":77779,"journal":{"name":"Renal physiology","volume":"10 5","pages":"261-71"},"PeriodicalIF":0.0,"publicationDate":"1987-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000173134","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14456804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Osmotic diuresis. 渗透性利尿。

Renal physiology Pub Date : 1987-01-01 DOI: 10.1159/000173127

F Lang

引用次数: 4

Potassium-sparing diuretics. 保钾利尿剂。

Renal physiology Pub Date : 1987-01-01 DOI: 10.1159/000173130

J D Horisberger, G Giebisch

{"title":"Potassium-sparing diuretics.","authors":"J D Horisberger, G Giebisch","doi":"10.1159/000173130","DOIUrl":"https://doi.org/10.1159/000173130","url":null,"abstract":"Amiloride, triamterene, and the spirolactones are potassium-sparing diuretics which act on the distal parts of the nephron, from the late distal tubule to the collecting duct. In these segments, active sodium reabsorption occurs through the following mechanism: sodium ions enter the cell through specific channels present in the luminal membrane and are extruded out of the cell into the peritubular medium by a sodium-potassium exchange pump, the Na-K-ATPase. Amiloride in micromolar concentrations reduces the sodium transport by blocking the luminal membrane sodium channel. Triamterene has a similar effect, although with a lower affinity; the available studies do not allow to determine if an inhibitory effect of triamterene on the Na-K-ATPase plays an additional role in its diuretic action. The spirolactones are competitive inhibitors of aldosterone, the mineralocorticoid hormone which promotes sodium reabsorption by increasing both the number of active sodium channels in the luminal membrane and the number of active Na-K pumps in the peritubular membrane. By the inhibitory effect on the electrogenic sodium transport, amiloride, triamterene, and the spirolactones decrease the lumen-negative transepithelial potential difference. This reduces the driving force for potassium movement into the tubular lumen and thus decreases potassium excretion.","PeriodicalId":77779,"journal":{"name":"Renal physiology","volume":"10 3-4","pages":"198-220"},"PeriodicalIF":0.0,"publicationDate":"1987-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000173130","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13602769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 37

Unilateral renal arterial infusion and renal vein catheterization in rabbits. Study of renal function and renin release. 家兔单侧肾动脉输注及肾静脉置管。肾功能和肾素释放的研究。

Renal physiology Pub Date : 1987-01-01 DOI: 10.1159/000173118

K W Cho, G Y Koh, S H Kim, K H Seul

引用次数: 5

Effects of administered thromboxanes on the intact, normal rat kidney. 给药血栓素对完整正常大鼠肾脏的影响。

Renal physiology Pub Date : 1987-01-01 DOI: 10.1159/000173120

C Baylis

引用次数: 44

Renal effects of angiotensin II: role of prostaglandins? 血管紧张素II对肾脏的影响:前列腺素的作用?

Renal physiology Pub Date : 1987-01-01 DOI: 10.1159/000173117

J Shohat, A Erman, G Boner, J B Rosenfeld

引用次数: 4

Participation of the prostaglandin system in furosemide-induced changes of renal function in anesthetized rats. 前列腺素系统参与速尿致麻醉大鼠肾功能改变。

Renal physiology Pub Date : 1987-01-01 DOI: 10.1159/000173110

M Yoshida, M Suzuki-Kusaba, S Satoh

引用次数: 13

Marginal effect of changes in acid-base status in vitro on rheogenic H+ and HCO3- secretion in turtle urinary bladder. 体外酸碱状态变化对龟膀胱流变性H+和HCO3-分泌的边际影响。

Renal physiology Pub Date : 1987-01-01 DOI: 10.1159/000173116

H J Adrogué, J Tasby, G Ulate

{"title":"Marginal effect of changes in acid-base status in vitro on rheogenic H+ and HCO3- secretion in turtle urinary bladder.","authors":"H J Adrogué, J Tasby, G Ulate","doi":"10.1159/000173116","DOIUrl":"https://doi.org/10.1159/000173116","url":null,"abstract":"This study systematically evaluates the effect of changes in the acid-base composition of the incubation media on the electrogenic H+ and HCO3- secretion (voltage clamp method and serosal ouabain) in the isolated turtle urinary bladder. Since the various cell types would change their acidity in a similar direction but to a variable degree, measured mean cell pH values (5,5-dimethyl-2,3-oxazolidinedione method) were used for an overall assessment of the changes in the acid-base status of the acid-transporting cells. Although addition of exogenous CO2 (0.7-3%) increased H+ secretion (JH+) 2- to 4-fold from a CO2-free control period, a further increase in the percent of CO2 did not enhance JH+ demonstrating a permissive but not a stimulatory role of CO2. Cyclic AMP plus 3-isobutyl-1-methylxanthine-induced electrogenic HCO3 secretion (JHCO3-) remained unaltered at 10% CO2 from a 5% CO2 control period. Cell acidosis resulting from either alterations in the PCO2/HCO3- levels or from NH4Cl in the bathing solution did not enhance JH+; by contrast maximal levels of acidification were found at cell pH values of about 7.40 and comparable effects on JH+ were found with a variety of PCO2/HCO3- combinations that led to a similar intracellular acidity.","PeriodicalId":77779,"journal":{"name":"Renal physiology","volume":"10 2","pages":"69-84"},"PeriodicalIF":0.0,"publicationDate":"1987-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000173116","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13971790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Carbonic anhydrase inhibitors. 碳酸酐酶抑制剂。

Renal physiology Pub Date : 1987-01-01 DOI: 10.1159/000173126

P A Preisig, R D Toto, R J Alpern

引用次数: 19