Renal physiology最新文献_第5页

Effects of a calcium channel agonist on renin release from perfused rat kidneys. 钙通道激动剂对灌注大鼠肾脏肾素释放的影响。

Renal physiology Pub Date : 1986-01-01 DOI: 10.1159/000173092

J R Dietz

引用次数: 6

Evidence that alpha-1-adrenergic stimuli specifically increase gluconeogenesis of the isolated proximal convoluted tubule in the rat. α -1肾上腺素能刺激特异性增加大鼠离体近曲小管糖异生的证据。

Renal physiology Pub Date : 1986-01-01 DOI: 10.1159/000173086

J Nakada, H Yamada, H Endou

{"title":"Evidence that alpha-1-adrenergic stimuli specifically increase gluconeogenesis of the isolated proximal convoluted tubule in the rat.","authors":"J Nakada, H Yamada, H Endou","doi":"10.1159/000173086","DOIUrl":"https://doi.org/10.1159/000173086","url":null,"abstract":"Isolated kidney-cortical tubule suspensions and microdissected nephron segments from fed rats were used to study the action of catecholamines on gluconeogenesis. Gluconeogenesis from rat tubule suspension incubated with 5 mM pyruvate was stimulated maximally by 10(-5) M methoxamine, an alpha 1-selective agonist, and 10(-6) M noradrenaline by 29.2 +/- 5.2% (mean +/- SEM) and 32.6 +/- 2.9%, respectively. These effects were completely inhibited by 10(-7) M prazosin, a beta 1-selective antagonist. Yohimbine, an alpha 2-antagonist, also inhibited the effect, but only at a higher concentration (5 X 10(-5) M). Gluconeogenesis was not stimulated by isoproterenol, a alpha-agonist, at any concentrations between 10(-5) and 10(-7) M. With microdissected nephron segments, only the proximal tubule possessed gluconeogenic activity. Within the proximal tubule, the proximal convoluted tubule (PCT) revealed higher gluconeogenic activity than the proximal straight tubule (PST). Methoxamine at 10(-5) M stimulated gluconeogenesis in PCT, whereas in PST no increase of gluconeogenesis was observed. From these results, it can be concluded that an alpha 1-adrenergic agonist specifically stimulates renal gluconeogenesis in PCT, but not in PST.","PeriodicalId":77779,"journal":{"name":"Renal physiology","volume":"9 4","pages":"213-22"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000173086","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14011143","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: 5

Antihypertensive and bilateral renal responses to nifedipine in 2-kidney, 1-clip, Goldblatt hypertensive rats. 硝苯地平对2肾1夹Goldblatt高血压大鼠的降压和双侧肾脏反应。

Renal physiology Pub Date : 1986-01-01 DOI: 10.1159/000173081

W C Huang

{"title":"Antihypertensive and bilateral renal responses to nifedipine in 2-kidney, 1-clip, Goldblatt hypertensive rats.","authors":"W C Huang","doi":"10.1159/000173081","DOIUrl":"https://doi.org/10.1159/000173081","url":null,"abstract":"Experiments were performed to assess the effects of nifedipine, a calcium channel blocker, on the blood pressure and bilateral renal function in 2-kidney, 1-clip, Goldblatt hypertensive rats. Hypertensive rats were prepared 4 weeks prior to the acute experiments, Nifedipine was administered intravenously into hypertensive (n = 11) and control (n = 12) rats under pentobarbital anesthesia. In hypertensive rats, nifedipine (0.02 mg/kg) reduced the mean arterial pressure from 151 +/- 5 to 135 +/- 5 mm Hg. Despite the fall of arterial pressure, there were significant increases in glomerular filtration rate (GFR) from 1.36 +/- 0.13 to 1.80 +/- 0.22 ml/min, urine flow from 7.8 +/- 1.6 to 17.0 +/- 3.8 microliter/min, and excretions of absolute and fractional sodium from 1.07 +/- 0.43 mu Eg/min and 0.50 +/- 0.15% to 2.80 +/- 0.73 mu Eq/min and 0.92 +/- 17%, respectively, in the nonclipped kidney. No significant changes in these renal indices occurred in the clipped kidney. In control rats, administration of nifedipine (0.04 mg/kg) also significantly decreased the arterial pressure from 119 +/- 4 to 110 +/- 4 mm Hg. There were slight but insignificant increases in GFR and renal excretion of sodium and water. In both groups, nifedipine produced proportionate increases in osmolar clearance and free water reabsorption. These results suggest that nifedipine enhances glomerular filtration and suppresses the reabsorption of sodium and water by the proximal tubule and/or distal nephron segments. The resulting increase in excretory function of the nonclipped kidney may, in part, contribute to the blood pressure-lowering effect of this drug.","PeriodicalId":77779,"journal":{"name":"Renal physiology","volume":"9 3","pages":"167-76"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000173081","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14868792","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: 4

Age effects on the reactivity of antistreptococcal cell membrane antisera to murine glomerular basement membrane. In vitro versus in vivo analysis. 年龄对抗链球菌细胞膜抗血清对小鼠肾小球基底膜反应性的影响。体外与体内对比分析。

Renal physiology Pub Date : 1986-01-01 DOI: 10.1159/000173079

C F Lange, M Weber, R P Nayyar

{"title":"Age effects on the reactivity of antistreptococcal cell membrane antisera to murine glomerular basement membrane. In vitro versus in vivo analysis.","authors":"C F Lange, M Weber, R P Nayyar","doi":"10.1159/000173079","DOIUrl":"https://doi.org/10.1159/000173079","url":null,"abstract":"Antisera to the streptococcal cell membrane (SCM) were evaluated for their reactivity to murine glomerular basement membrane (GBM) in four strains of mice. Animals were studied on a daily basis from birth through 3 months and weekly thereafter through 18 months. Paired animals were compared for in vivo binding of antibody versus an indirect fluorescent antibody technique on fresh kidney sections. The findings demonstrated a granular type GBM staining for all anti-SCM which were positive. Nonspecific background staining accompanied most of the indirect fluorescent antibody sections tested while being totally absent for the direct fluorescent test on tissue from in vivo challenge of the primary antibody. The in vitro testing showed tissue from young mice (0-6 days old) to be most reactive, while the strongest reactivity was seen in the age group of 10-20 days for in vivo testing. These cross-reactive antibodies, i.e., GBM-binding anti-SCM, are best evaluated by in vivo methods where tissue is taken 4 days after antiserum injection. Animals of the age range 6-8 weeks were often negative, indicating that this age range selected for many studies may not be the most favorable one via either in vitro or in vivo studies.","PeriodicalId":77779,"journal":{"name":"Renal physiology","volume":"9 3","pages":"148-59"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000173079","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14651842","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: 3

Macula densa control of renin secretion and glomerular vascular tone: evidence for common cellular mechanisms. 黄斑致密控制肾素分泌和肾小球血管张力:共同细胞机制的证据。

Renal physiology Pub Date : 1986-01-01 DOI: 10.1159/000173084

J P Briggs, J Schnermann

{"title":"Macula densa control of renin secretion and glomerular vascular tone: evidence for common cellular mechanisms.","authors":"J P Briggs, J Schnermann","doi":"10.1159/000173084","DOIUrl":"https://doi.org/10.1159/000173084","url":null,"abstract":"The macula densa is believed to function as a sensor for control of intrarenal vascular tone and renin secretion. Increases in flow rate through the loop of Henle or increases in distal tubular fluid NaCl concentration result in an increase in local vascular tone and a decrease in glomerular filtration rate, the tubuloglomerular feedback (TGF) mechanism. Increases in distal NaCl concentration are also believed to inhibit renin secretion. Evidence will be reviewed that suggests that these two processes may be activated concurrently and may share common cellular mechanisms. Similarities in the sensor step include a similar pattern of ion specificity, with both responses being relatively anion specific but showing little cation specificity. TGF responses are inhibitable by furosemide, and the renin secretion produced by furosemide seems to be in part macula densa dependent. There appear also to be common features in the effector step of both responses. Increases in intracellular calcium are implicated in both the vasoconstrictive response seen with increased macula densa NaCl concentration and in inhibition of renin secretion. Changes in cyclic AMP may play a role in the converse responses.","PeriodicalId":77779,"journal":{"name":"Renal physiology","volume":"9 4","pages":"193-203"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000173084","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14651845","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: 39

Epithelial cell volume regulation illustrated by experiments in frog skin. 青蛙皮肤上皮细胞体积调节的实验研究。

Renal physiology Pub Date : 1986-01-01 DOI: 10.1159/000173074

H H Ussing

引用次数: 38

Whole kidney response to reduced arterial pressure during converting enzyme inhibition in the rat. 大鼠转换酶抑制期间全肾对降低动脉压的反应。

Renal physiology Pub Date : 1986-01-01

A Göransson, B Isaksson, M Sjöquist

{"title":"Whole kidney response to reduced arterial pressure during converting enzyme inhibition in the rat.","authors":"A Göransson, B Isaksson, M Sjöquist","doi":"","DOIUrl":"","url":null,"abstract":"Autoregulatory efficiency of renal blood flow (RBF) and glomerular filtration rate (GFR) was evaluated in male Sprague-Dawley rats during interference with the renin-angiotensin system by a converting enzyme inhibitor (CEI), captopril (3 mg X h-1 X kg-1 BW). RBF and GFR were approximately 25 (p less than 0.01) and 20% (p less than 0.02) higher, respectively, in rats infused with CEI than in control rats at spontaneous renal arterial pressure (RAP). A reduction of RAP to 100 mm Hg (within the autoregulatory range) resulted in effective autoregulation of GFR and RBF in control rats. In rats given CEI, however, the autoregulation of GFR was markedly impaired. GFR decreased by 35% (p less than 0.001), while RBF remained relatively unchanged. This caused the filtration fraction to decrease from 0.33 +/- 0.01 to 0.29 +/- 0.01 (p less than 0.001). RAP had a consistent effect on the urine flow rate, even though both GFR and RBF were well autoregulated in control rats. No significant decrease in electrolyte excretion was detected within the autoregulatory range in control rats, but during converting enzyme blockade this excretion decreased progressively as RAP was reduced, and the decrease correlated well to the reduction in GFR. In summary, these results suggest that the renin-angiotensin system plays an important intrarenal role in the autoregulation of GFR, probably through an efferent arteriolar mechanism. Furthermore, it is demonstrated that the contralateral kidney efficiently compensates in urinary electrolyte excretion for an acute unilateral reduction of RAP.(ABSTRACT TRUNCATED AT 250 WORDS)","PeriodicalId":77779,"journal":{"name":"Renal physiology","volume":"9 5","pages":"287-301"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14666428","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: 0

Effect of carbonic anhydrase inhibition on (U-B)pCO2 in the alkaline urine of the rabbit. 碳酸酐酶抑制对家兔碱性尿液(U-B)pCO2的影响。

Renal physiology Pub Date : 1986-01-01 DOI: 10.1159/000173098

M Kekomäki, T H Maren, C S Wingo

{"title":"Effect of carbonic anhydrase inhibition on (U-B)pCO2 in the alkaline urine of the rabbit.","authors":"M Kekomäki, T H Maren, C S Wingo","doi":"10.1159/000173098","DOIUrl":"https://doi.org/10.1159/000173098","url":null,"abstract":"We studied factors influencing urine pCO2 minus blood pCO2 [(U-B)pCO2] in rabbits infused with sodium bicarbonate solutions. Unlike other species, the rabbit does not develop a significant (U-B)pCO2 (urine pCO2 greater than blood pCO2) after alkali or acid buffer infusion. However, intravenous acetazolamide immediately induced a significant (U-B)pCO2. The effect could not be related to the blood pH or pCO2, the urinary concentration of bicarbonate or inorganic phosphate, or to changes in plasma potassium concentration. Methazolamide was also effective in increasing (U-B)pCO2. This significant (U-B)pCO2 was present after carbonic anhydrase inhibition in rabbits subjected to chronic partial obstruction of urinary flow and in rabbits treated with 11-desoxycorticosterone acetate (DOCA). We propose that carbon dioxide is normally dissipated from the alkaline urine of the rabbit by a distal tubular mechanism, which involves catalytic conversion of carbon dioxide to bicarbonate. Inhibition of carbonic anhydrase leads to the formation of a significant (U-B)pCO2. In the rabbit, pCO2 may be an index of collecting duct acidification under certain circumstances; however, the relation of collecting duct acidification to the high (U-B)pCO2 during the inhibition of carbonic anhydrase remains to be determined.","PeriodicalId":77779,"journal":{"name":"Renal physiology","volume":"9 6","pages":"326-34"},"PeriodicalIF":0.0,"publicationDate":"1986-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000173098","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14242224","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: 1

Urinary kinin excretion following alterations of vasopressin levels in man and rat. 人与大鼠抗利尿激素水平变化后尿激肽排泄。

Renal physiology Pub Date : 1986-01-01

A Náray-Fejes-Tóth, G Fejes-Tóth

引用次数: 0

Acute effects of various diuretics on lithium clearance. Studies in rats on medium and low sodium diet. 各种利尿剂对锂清除的急性影响。中、低钠饮食大鼠的研究。

Renal physiology Pub Date : 1986-01-01

K Thomsen, P P Leyssac

引用次数: 0