scholarly journals Functional Relevancies of Trans-Differentiation in the Juxtaglomerular Apparatus of Rat Kidney

2020 ◽  
Vol Volume 13 ◽  
pp. 147-156
Author(s):  
Zsolt Razga
Keyword(s):  
Rat Kidney ◽  
Juxtaglomerular Apparatus

Glucose-6-phosphate dehydrogenase and renin in kidneys of hypertensive or adrenalectomized rats

1959 ◽  
Vol 197 (4) ◽  
pp. 869-872 ◽  
Author(s):  
R. Hess ◽  
F. Gross
Keyword(s):  
Enzymatic Activity ◽  
Rat Kidney ◽  
Juxtaglomerular Apparatus ◽  
Macula Densa ◽  
Sodium Balance ◽  
Normal Rat ◽  
Distal Tubules ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Renin Content ◽  
Intact Rats

Using a histochemical method, moderately strong glucose-6-phosphate dehydrogenase activity can be demonstrated in the macula densa of the distal tubules in the normal rat kidney. In rats rendered hypertensive by overdosage with cortexone (DOC) and saline, this enzymatic activity was found to decrease almost to zero within 4 weeks. This change was more marked in unilaterally nephrectomized animals than in intact rats. Measured by bioassay, the renin content of kidney extracts from the same animals was found to decrease simultaneously with the loss of enzymatic activity in the macula cells. The reverse effect, a marked increase in activity of the macula densa, was obtained in adrenalectomized animals. It is suggested that both the macula densa cells and the juxtaglomerular apparatus are parts of a system which respond similarly to changes in sodium balance and which may be related to the formation of renin.

Autoradiographic demonstration of oxytocin-binding sites in the macula densa

1989 ◽  
Vol 257 (2) ◽  
pp. F310-F314 ◽  
Author(s):  
M. E. Stoeckel ◽  
M. J. Freund-Mercier
Keyword(s):  
Binding Sites ◽  
Cellular Localization ◽  
Rat Kidney ◽  
Juxtaglomerular Apparatus ◽  
Macula Densa ◽  
Tubuloglomerular Feedback ◽  
Binding Characteristics ◽  
Conventional Film ◽  
High Concentrations ◽  
Autoradiographic Technique

Specific oxytocin (OT)-binding sites were localized in the rat kidney with use of a selective 125I-labeled OT antagonist (125I-OTA). High concentrations of OT binding sites were detected on the juxtaglomerular apparatus with use of the conventional film autoradiographic technique. No labeling occurred on other renal structures. The cellular localization of the OT binding sites within the juxtaglomerular apparatus was studied in light microscope autoradiography, on semithin sections from paraformaldehyde-fixed kidney slices incubated in the presence of 125I-OTA. These preparations revealed selective labeling of the macula densa, mainly concentrated at the basal pole of the cells. Control experiments showed first that 125I-OTA binding characteristics were not noticeably altered by prior paraformaldehyde fixation of the kidneys and second that autoradiographic detection of the binding sites was not impaired by histological treatments following binding procedures. In view of the role of the macula densa in the tubuloglomerular feedback, the putative OT receptors of this structure might mediate the stimulatory effect of OT on glomerular filtration.

Parallel regulation of constitutive NO synthase and renin at JGA of rat kidney under various stimuli

1995 ◽  
Vol 269 (6) ◽  
pp. F793-F805 ◽  
Author(s):  
H. M. Bosse ◽  
R. Bohm ◽  
S. Resch ◽  
S. Bachmann
Keyword(s):  
Gene Expression ◽  
Rat Kidney ◽  
Distal Tubule ◽  
Juxtaglomerular Apparatus ◽  
Renal Perfusion ◽  
Salt Transport ◽  
Sham Operation ◽  
Type I ◽  
Salt Loading ◽  
Salt Diet

Four chronic experiments were performed to assess changes in the activity and gene expression of type I nitric oxide synthase (NOS) at the macula densa (MD) and of renin expression and immunoreactivity (IR) at the juxtaglomerular apparatus (JGA) of rat kidney, as follows: 1) two-kidney, one-clip Goldblatt hypertension (2K1C, for 3 and 40 days; sham operation for controls), 2) furosemide treatment (150 mg/kg-1.day-1 ip for 5 days), 3) chronic low-salt diet (0.02%) vs. high-salt diet (3%; both for 11 days), and 4) chronic blockade of NOS by nitro-L-arginine methyl ester (L-NAME, 40 mg.kg-1.day-1 for 2 mo). NOS and renin gene expression, NOS enzyme activity and renin IR were semiquantitatively evaluated with histochemical methods (NADPH diaphorase, in situ hybridization, immunohistochemistry). In 2K1C, marked increases were induced in NOS and renin in the ischemic vs. contralateral kidneys both after 3 and 40 days, respectively (P < 0.05). Related to controls, significant increases in the ischemic kidney were encountered after 3 and 40 days, whereas contralateral suppression of NOS and renin was found only after 40 days. Furosemide treatment resulted in a marked increase of both NOS and renin levels compared with controls (P < 0.05). Salt restriction induced a significant elevation of NOS levels compared with salt loading (P < 0.05), whereas only minor changes were evident in renin levels. L-NAME treatment resulted in a moderate reduction of NOS activity (not significant), whereas renin levels were markedly reduced (P < 0.05). These results show that NOS activity and gene expression are inversely related to chronic changes in renal perfusion, salt balance, and salt transport at the distal tubule in parallel with the known response of renin to these changes. Inhibition of NOS decreases renin levels at the JGA. The histochemical findings support previous concepts that MD-derived NO is involved in the control of renin synthesis.

Localization of kallikrein in the rat kidney and its anatomical relationship to renin.

1982 ◽  
Vol 30 (4) ◽  
pp. 385-390 ◽  
Author(s):  
T B Orstavvik ◽  
T Inagami
Keyword(s):  
Collecting Duct ◽  
Rat Kidney ◽  
Distal Tubule ◽  
Juxtaglomerular Apparatus ◽  
Thick Ascending Limb ◽  
Loop Of Henle ◽  
Afferent Arteriole ◽  
Epitheloid Cells ◽  
Anatomical Relationship

The anatomical relationship between kallikrein and renin in the rat kidney was investigated immunohistochemically by the peroxidase-antiperoxidase method. Kallikrein was localized to the convoluted distal tubule, starting at a point, distal to the juxtaglomerular apparatus, where the thick ascending limb of loop of Henle transformed into the convoluted distal tubule. The thick ascending limb was identified by its content of uromucoid (Tamm-Horsfall glycoprotein). Kallikrein was never observed within the juxtaglomerular apparatus itself. The kallikrein-containing tubule ended where the distal tubule submerged into the collecting duct. Renin was found in epitheloid cells of the afferent arteriole. When neighboring sections were stained for kallikrein and renin, respectively, no close anatomical relationship was observed between the kallikrein-containing and the renin-containing structures.

The juxtaglomerular apparatus in the normal rat kidney

1978 ◽  
Vol 379 (2) ◽  
pp. 143-150 ◽  
Author(s):  
Jan A. Christensen ◽  
Adalbert Bohle
Keyword(s):  
Rat Kidney ◽  
Juxtaglomerular Apparatus ◽  
Normal Rat

Oxytocin receptors in rat kidney during development

1990 ◽  
Vol 259 (6) ◽  
pp. F872-F881 ◽  
Author(s):  
A. Schmidt ◽  
S. Jard ◽  
J. J. Dreifuss ◽  
E. Tribollet
Keyword(s):  
Binding Sites ◽  
Specific Binding ◽  
Rat Kidney ◽  
Distal Tubule ◽  
Juxtaglomerular Apparatus ◽  
Binding Studies ◽  
Single Class ◽  
Ligand Selectivity ◽  
Oxytocin Receptors ◽  
Two Stages

The development and characteristics of oxytocin (OT) receptors in the rat kidney were studied by light-microscopic autoradiography and on membrane preparations using the iodinated OT antagonist 125I-d(CH2)5[Tyr(Me)2,Thr4,Orn8,Tyr(NH2)9]OT. Specific binding was first detected by autoradiography at embryonic day 17 (E17) in both the cortex and the medulla. Cortical labeling was found thereafter at all ages examined including in the adult (postnatal day 90, PN90). It was localized on the distal tubule at the level of the juxtaglomerular apparatus. Medullary binding was detected only transiently during two stages of development, first, before PN6, and second, at the approximate time of weaning (PN20-PN30). Binding studies on crude membranes prepared from whole kidneys of animals aged between PN1 and PN15 showed a single class of high-affinity binding sites, with a dissociation constant of 0.13 +/- 0.08 nM. Thus transient OT binding sites expressed in the medulla do not differ from cortical OT binding sites; moreover, the ligand selectivity of kidney OT receptors regardless of location and age appears similar to that of previously characterized OT receptors. Our results suggest that OT may play a role in both renal development and renal function.

Neuropeptide Y: a novel renal peptide with vasoconstrictor and natriuretic activity

1985 ◽  
Vol 68 (4) ◽  
pp. 373-377 ◽  
Author(s):  
J. M. Allen ◽  
A. E. G. Raine ◽  
J. G. G. Ledingham ◽  
S. R. Bloom
Keyword(s):  
Neuropeptide Y ◽  
Perfusion Pressure ◽  
Rat Kidney ◽  
Juxtaglomerular Apparatus ◽  
Renal Perfusion ◽  
Sodium Reabsorption ◽  
Potent Vasoconstrictor ◽  
Dose Dependent Increase ◽  
Dose Dependent ◽  
Vasoconstrictor Peptide

1. A novel vasoconstrictor peptide, neuropeptide Y (NPY), has been identified in considerable quantities in the renal artery and kidney. Within the kidney, NPY was confined to the cortex and corticomedullary interface, the regions where the juxtaglomerular apparatus is most numerous. 2. In the isolated perfused rat kidney, NPY caused a prompt dose-dependent increase in perfusion pressure and reduction in flow, with only a small fall in glomerular filtration rate (GFR). In spite of the reduced renal perfusion, a dose-dependent natriuresis was observed. This response contrasts to the response of this preparation to noradrenaline, which causes sodium reabsorption. 3. The presence of a potent vasoconstrictor and natriuretic peptide within the rat renovascular system suggests that it may play a significant role in the control of renal function.

Localization of dopamine D1A receptor protein in rat kidneys

1995 ◽  
Vol 268 (6) ◽  
pp. F1185-F1197 ◽  
Author(s):  
D. P. O'Connell ◽  
S. J. Botkin ◽  
S. I. Ramos ◽  
D. R. Sibley ◽  
M. A. Ariano ◽  
...  
Keyword(s):  
Collecting Duct ◽  
Rat Kidney ◽  
Distal Tubule ◽  
Juxtaglomerular Apparatus ◽  
Receptor Protein ◽  
Receptor Subtype ◽  
Cortical Collecting Duct ◽  
Binding Studies ◽  
Electron Microscopic ◽  
Renal Vasculature

The dopamine D1A receptor subtype was identified in rat kidney with both light microscopic immunohistochemistry and electron microscopic immunocytochemistry. Antipeptide polyclonal antisera were directed to both extracellular and intracellular regions of the native receptor. The use of such receptor-subtype-selective antibodies allows for the identification of specific dopamine receptor subtype clones that are not distinguished by current pharmacological or receptor-ligand binding technology. Selectivity of the antipeptide antisera was validated by their ability to recognize native receptor protein expressed in permanently transfected mouse LTK- cells. In the rat kidney, D1A receptor protein was localized to the juxtaglomerular apparatus (JGA), proximal tubule, distal tubule, cortical collecting duct, and renal vasculature. In the JGA, the receptor was predominantly located in the arteriolar smooth muscle layer within cytoplasmic granules previously shown to contain renin. In the proximal tubules, staining was localized both on the brush-border and basolateral membranes. The D1A receptor, which is present in the central nervous system, is now identified in the rat kidney at those sites previously labeled as DA1 receptor sites on the basis of pharmacological binding studies. These results suggest that at least some of the renal dopamine DA1 receptors correspond structurally to the central dopamine D1A receptor.

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