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Journal ArticleDOI

H3 receptor renal expression in normal and diabetic rats

07 Mar 2015-Inflammation Research (Springer Basel)-Vol. 64, Iss: 5, pp 271-273

TL;DR: H3R is expressed in the apical membrane by collecting duct cells in the kidney of rats and it is significantly increased in diabetic animals, suggesting its involvement in fluid homeostasis.

AbstractTo extend our previous observation of H4R upregulation in the kidney of diabetic rats, we evaluated in the same specimens the presence of the H3R. Kidney specimens from 24 8-week-old male Wistar rats (12 non-diabetic and 12 diabetic animals) were processed for both immunohistochemical and immunofluorescence analyses. H3R is expressed in the apical membrane by collecting duct cells in the kidney of rats and it is significantly increased in diabetic animals. These data support the hypothesis that H3R could also mediate non-neuronal histamine effects, suggesting its involvement in fluid homeostasis.

Topics: Apical membrane (57%), Kidney (55%), Diabetes mellitus (51%)

Summary (2 min read)

Introduction

  • Recently, their group demonstrated the presence of the histamine H4 receptor (H4R) in resident renal cells of the loop of Henlé and its profound upregulation in the kidney of diabetic rats[1].
  • In renal transplant patients the urinary and blood levels of histamine are elevated.
  • In the kidney of diabetic rats, histamine was increased compared with controls[2].
  • Basically, histamine has been reported to regulate the renal microcirculation, to increase salt and water excretion[3-5], decrease the ultrafiltration coefficient by reducing the total filtration surface area[4], and increase renin release[6].
  • The aim of this study was to extend their previous observation on H4R in healthy and diabetic rats evaluating in the same specimens the renal expression of H3R.

Materials and Methods

  • Animals, protocols, diabetes induction, biochemical and histological parameters have been previously reported[1].
  • Conventional immunohistochemical procedures were employed as described.
  • Renal sections were incubated overnight with anti-H3R (349–358) (2 µg/ml)[7], followed by a three-layer streptavidin–biotin–peroxidase complex staining method.
  • After counterstaining with DAPI, photomicrographs were obtained by Apotome systems at x40 objective.
  • Values are expressed as mean ± SEM positive cell/collecting duct percentage of individual rats (ten images/zone each) from the different experimental groups.

Results

  • The immunohistochemical analysis (Fig. 1A) revealed a clear H3R-like immunoreactivity in control rats, predominantly in the renal medulla and the papilla.
  • In contrast, in the cortex the immunoreactivity was generally very low, and no signal was detected in the glomeruli.
  • Notably, when diabetic and non-diabetic animals were compared, a significant increase in immunoreactivity, suggestive of H3R receptor upregulation, was observed (Fig 1B).
  • The above data, indicating a higher H3R-like immunoreactivity in the apical membrane of epithelial tubular cells mosty located in medulla and papilla, suggested a collecting duct expression profile for the receptor.
  • To confirm this result, immunoflorescence co-staining was performed with AQP2, expressed in the apical membrane by collecting duct cells in the kidney.

Discussion

  • The authors demonstrate for the first time that the H3R is mainly expressed in the apical membrane by collecting duct cells of the rat, and that this protein is significantly upregulated in the kidneys of diabetic animals.
  • The authors histochemical data add the collecting duct cells to the growing list of non-neuronal H3R-expressing cells already reported[7-9], thus providing further evidence for a role of H3R in mediating non-neuronal histamine effects.
  • The collecting duct plays a pivotal role in kidney function and homeostasis by regulating ions and water transport.
  • The ability to concentrate urine is impaired in conditions such as diabetes insipidus, Histamine, whose levels have been reported to be increased in the kidney of diabetic animals[2], has been shown to increase salt and water excretion[8-10].
  • Whether this receptor has a compensatory or pathological implication and its role as a pharmacological target in diabetic nephropathy remains to be established.

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10 August 2022
AperTO - Archivio Istituzionale Open Access dell'Università di Torino
Original Citation:
H3 receptor renal expression in normal and diabetic rats
Published version:
DOI:10.1007/s00011-015-0808-y
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This version is available http://hdl.handle.net/2318/158681 since 2016-11-11T15:28:57Z

The final publication is available at Springer via
http://www.springerlink.com/openurl.asp?genre=article&id=doi:10.1007/
s00011-015-0808-y

H
3
receptor renal expression in normal and diabetic rats.
Alessandro Pini
1*
, Paul L Chazot
2*
, Eleonora Veglia
3
, Aldo Moggio
3
, Arianna Carolina Rosa
3
*
Authors contributed equally to this work
1
Dipartimento di Medicina Sperimentale e Clinica Sezione di Anatomia e Istologia Università degli Studi di Firenze,
Largo Brambilla 3, 50134 Florence, Italy;
2
School of Biological and Biomedical Sciences and Wolfson Research
Institute, Durham University, South Road, Durham DH1 3LE, UK;
3
Dipartimento di Scienza e Tecnologia del
Farmaco, Università di Torino, Via P. giuria 9, 10125 Turin, Italy;
Corresponding authors Arianna Carolina Rosa, PhD
Dipartimento di Scienza e Tecnologia del Farmaco, University of Turin, Italy, Via P.
Giuria 9, 10125, Turin, Italy
Phone: +390116707955
Fax: +390116707688
e-mail: ariannacarolina.rosa@unito.it

Abstract
Introduction
In order to extend our previous observation of H
4
R upregulation in the kidney of diabetic rats, we evaluated in the same
specimens the presence of the H
3
R.
Materials and methods
Kidney specimens from 24 8-week-old male Wistar rats (12 non-diabetic and 12 diabetic animals) were processed for
both immunohistochemical and immunofluorescence analyses.
Results and conclusion
H
3
R is expressed in the apical membrane by collecting duct cells in the kidney of rats and it is significantly increased in
diabetic animals. These data support the hypothesis that H
3
R could also mediate non-neuronal histamine effects,
suggesting its involvement in fluid homeostasis.
Key Words histamine H
3
receptor, histamine, kidney, diabetes, collecting ducts

Introduction
Recently, our group demonstrated the presence of the histamine H
4
receptor (H
4
R) in resident renal cells of the loop of
Henlé and its profound upregulation in the kidney of diabetic rats[1]. This observation adds to independent evidence of
a role for histamine in renal (patho)physiology. In healthy subjects the administration of loading doses of L-histidine led
to an increase of histamine concentration in urine. In renal transplant patients the urinary and blood levels of histamine
are elevated. In the kidney of diabetic rats, histamine was increased compared with controls[2]. Basically, histamine has
been reported to regulate the renal microcirculation, to increase salt and water excretion[3-5], decrease the ultrafiltration
coefficient by reducing the total filtration surface area[4], and increase renin release[6].
The aim of this study was to extend our previous observation on H
4
R in healthy and diabetic rats evaluating in the same
specimens the renal expression of H
3
R.
Materials and Methods
Animals, protocols, diabetes induction, biochemical and histological parameters have been previously reported[1].
Conventional immunohistochemical procedures were employed as described. Immunoperoxidase staining for H
3
R was
performed on 5 µm kidney sections for formalin-fixed tissue from 24 male 8-week-old Wistar rats (12 non-diabetic and
12 diabetic animals). Renal sections were incubated overnight with anti-H
3
R (349358) (2 µg/ml)[7], followed by a
three-layer streptavidinbiotinperoxidase complex staining method. Photomicrographs were acquired randomly with a
digital camera connected to a light microscope equipped with a x40 objective (Leica DM750). Images were processed
by ImageJ 1.41 (NIH, USA) software and quantified using the Color Deconvolution image analysis tool. The per-
centage area was calculated for H
3
R-positive tissue. Values are mean ± SEM of the optical density (in arbitrary units)
measurements of individual rats (ten images/zone each) from the different experimental groups. For
immunofluorescence and confocal analysis, after antigen retrieval and blocking, kidney sections were incubated with
primary anti-H
3
R and anti-AQP2, antibody, followed by incubation with corresponding Alexa Fluor secondary
antibodies. After counterstaining with DAPI, photomicrographs were obtained by Apotome systems (Zeiss) at x40
objective. The percentage of positive cells for H
3
R and AQP2 was determine by ImageJ 1.41 software. Values are
expressed as mean ± SEM positive cell/collecting duct percentage of individual rats (ten images/zone each) from the
different experimental groups.
To confirm the absence of false staining, tissue was also screened in the absence of primary antibodies and following
pre-incubation with (349-358) peptide (data not shown). All sections were immunostained in a single session to
minimize artifactual differences.

Citations
More filters

Journal ArticleDOI
TL;DR: An interesting upsurge in the field which provides scope for new insights into the role of histamine in diabetes is revealed.
Abstract: The first studies of histamine and diabetes date back to the 1950s. Since that time the involvement of histamine in diabetes was related to its well known vasoactive properties and permeability leakage effects. In particular, the first evidence for a correlation between histamine and diabetes arose in 1989 when an increase in plasma and leucocyte histamine content was observed. Limited independent evidence followed in the subsequent two decades, focusing on both histamine glyceamic control and macro- and microvascular complications of diabetes. However, recent observations have sparked the question whether it is time to reconsider the functional contribution of histamine in diabetes. We reveal an interesting upsurge in the field which provides scope for new insights into the role of histamine in diabetes.

15 citations


Cites background from "H3 receptor renal expression in nor..."

  • ...Notably, 312 among them, both the H3R and the H4R have been reported to be profoundly upregulated at the 313 tubular level in STZ treated rats, which also displayed parallel renal damage (mostly again at the 314 tubular level) [33, 146]....

    [...]

  • ...Notably, the majority of these data were obtained 112 before the clear demonstration of H3R peripheral expression [16, 30-34]....

    [...]

  • ...independent, but sometimes contradictory; despite this heterogeniety, when viewing the timeline of 322 interest for histamine involvement in this disease (Figure 1) it appears phasic with a clear upturn 323 and renewal in interest in the last couple of years, thanks to the very recent discovery of a direct 324 effect of histamine on glycaemia [13, 16, 17] as well as a profound up-regulation of both H3R and 325 H4R in the diabetic animal kidney [33, 146]....

    [...]


Journal ArticleDOI
TL;DR: The data suggest that the H4R participates in diabetic nephropathy progression through both a direct effect on tubular reabsorption and an indirect action on renal tissue architecture via inflammatory cell recruitment, and H 4R antagonism emerges as a possible new multi‐mechanism therapeutic approach to counteract development of diabetic neephropathy development.
Abstract: Due to the incidence of diabetes and the related morbidity of diabetic nephropathy, identification of new therapeutic strategies represents a priority. In the last few decades new and growing evidence on the possible role of histamine in diabetes has been provided. In particular, the histamine receptor H 4 R is emerging as a new promising pharmacological target for diabetic nephropathy. The aim of this study was to evaluate the efficacy of selective H 4 R antagonism by JNJ39758979 on the prevention of diabetic nephropathy progression in a murine model of diabetes induced by streptozotocin injection. JNJ39758979 (25, 50, 100 mg/kg/day p.o.) was administered for 15 weeks starting from the onset of diabetes. Functional parameters were monitored throughout the experimental period. JNJ39758979 did not significantly affect glycaemic status or body weight. The urine analysis indicated a dose-dependent inhibitory effect of JNJ39758979 on Albumin-Creatinine- Ratio , the Creatinine Clearance, the 24 h urine volume, and pH urine acidification ( P 0.05). The beneficial effects of JNJ39758979 on renal function paralleled comparable effects on renal morphological integrity. These effects were sustained by a significant immune infiltration and fibrosis reduction. Notably, megalin and sodium-hydrogen-exchanger 3 expression levels were preserved. Our data suggest that the H 4 R participates in diabetic nephropathy progression through both a direct effect on tubular reabsorption and an indirect action on renal tissue architecture via inflammatory cell recruitment. Therefore, H 4 R antagonism emerges as a possible new multi-mechanism therapeutic approach to counteract development of diabetic nephropathy development.

12 citations


Cites background from "H3 receptor renal expression in nor..."

  • ...nterestingly, we demonstrated that renal H3R is predominantly ocalized on the collecting duct epithelium [7], a major regulator of ater reabsorption....

    [...]

  • ...Moreover, its expression was up-regulated in he kidney of both diabetic rats [7] and DBA2/J mice (Supplemenary Fig....

    [...]


Journal ArticleDOI
TL;DR: The evidence collected on the role of histamine in kidney function together with its well-known pleiotropic action suggest that this amine may act simultaneously on glomerular hyperfiltration, tubular inflammation, fibrosis development and tubular hypertrophy.
Abstract: The classification of diabetic nephropathy (DN) as a vascular complication of diabetes makes the possible involvement of histamine, an endogenous amine that is well known for its vasoactive properties, an interesting topic for study. The aim of the present review is to provide an extensive overview of the possible involvement of histamine in the onset and progression of DN. The evidence collected on the role of histamine in kidney function together with its well-known pleiotropic action suggest that this amine may act simultaneously on glomerular hyperfiltration, tubular inflammation, fibrosis development and tubular hypertrophy.

10 citations


Journal ArticleDOI
TL;DR: The data demonstrate that histamine, via the H1R, modifies SD morphological and functional integrity, in part, by decreasing the expression of ZO-1 and P-cadherin.
Abstract: Histamine has been reported to decrease the ultrafiltration coefficient, which inversely correlates with glomerular permselectivity, however the mechanism(s) underling this effect have never been investigated. This study aimed to assess whether histamine could exert a direct detrimental effect on podocyte permeability and the possible involvement of two key proteins for the glomerular slit diaphragm (SD) integrity, zonula occludens-1 (ZO-1) and P-cadherin. The effect of histamine (100 pM-1000nM) on coloured podocytes junctional integrity was evaluated functionally by a transwell assay of monolayer permeability and morphologically by electron microscopy. Histamine receptor (H1-4R) presence was evaluated at both mRNA (RT-PCR) and protein (immunofluorescence) levels. The Kd and Bmax values for [3H]mepyramine were determined by saturation binding analysis; IP1 and cAMP production evoked by histamine were measured by TR-FRET. ZO-1, P-cadherin and vimentin expression was assessed by qRT-PCR and quantitative immunoblotting. Histamine elicited a time- and sigmoidal dose-dependent (maximum effect at 8h, 10nM) increase in podocyte paracellular permeability widening the paracellular spaces. Only H1R was predominantly localised to the podocyte membrane. Consistently, histamine elicited a sigmoidal dose-dependent increase in IP1, but not in cAMP. Histamine exposure evoked a concentration-dependent reduction in both ZO-1 and P-cadherin and a parallel induction of vimentin mRNA expression with a maximum effect after 6h, and protein expression with a maximum effect after 8h. These effects were prevented by the selective H1R antagonist chlorpheniramine. In conclusion, our data demonstrate that histamine, via the H1R, modifies SD morphological and functional integrity, in part, by decreasing the expression of ZO-1 and P-cadherin.

9 citations


Cites background from "H3 receptor renal expression in nor..."

  • ...Indeed, the data on histamine 87 receptors expression on renal parenchymal cells arise only from our recent observations of H1R, 88 H2R, H3R and H4R on tubular epithelial cells [24-26]....

    [...]


Journal ArticleDOI
TL;DR: It is found that histamine is elevated in the plasma of a preclinical mouse model with severe cardiac dysfunction and showed that it acts protectively rather than harmfully on heart and kidney damages in this model, and that a histamine H3 agonist, Imm, prevents the cardiorenal damages.
Abstract: Heart failure and chronic kidney disease are major causes of morbidity and mortality internationally. Although these dysfunctions are common and frequently coexist, the factors involved in their relationship in cardiorenal regulation are still largely unknown, mainly due to a lack of detailed molecular targets. Here, we found the increased plasma histamine in a preclinical mouse model of severe cardiac dysfunction, that had been cotreated with angiotensin II (Ang II), nephrectomy, and salt (ANS). The ANS mice exhibited impaired renal function accompanied with heart failure, and histamine depletion, by the genetic inactivation of histidine decarboxylase in mice, exacerbated the ANS-induced cardiac and renal abnormalities, including the reduction of left ventricular fractional shortening and renal glomerular and tubular injuries. Interestingly, while the pharmacological inhibition of the histamine receptor H3 facilitated heart failure and kidney injury in ANS mice, administration of the H3 agonist immethridine (Imm) was protective against cardiorenal damages. Transcriptome analysis of the kidney and biochemical examinations using blood samples illustrated that the increased inflammation in ANS mice was alleviated by Imm. Our results extend the pharmacological use of H3 agonists beyond the initial purposes of its drug development for neurogenerative diseases and have implications for therapeutic potential of H3 agonists that invoke the anti-inflammatory gene expression programming against cardiorenal damages.

9 citations


Cites background from "H3 receptor renal expression in nor..."

  • ...Among these histamine receptor subtypes, H1 and H2 are expressed in the hearts and kidneys, and H3 is expressed in the ending of sympathetic nerves in these tissues (32, 33)....

    [...]


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TL;DR: The structure and function of the key transporters and the complex interplay of regulatory factors that modulate principal cell ion and water transport are addressed.
Abstract: The principal cell of the kidney collecting duct is one of the most highly regulated epithelial cell types in vertebrates. The effects of hormonal, autocrine, and paracrine factors to regulate principal cell transport processes are central to the maintenance of fluid and electrolyte balance in the face of wide variations in food and water intake. In marked contrast with the epithelial cells lining the proximal tubule, the collecting duct is electrically tight, and ion and osmotic gradients can be very high. The central role of principal cells in salt and water transport is reflected by their defining transporters-the epithelial Na(+) channel (ENaC), the renal outer medullary K(+) channel, and the aquaporin 2 (AQP2) water channel. The coordinated regulation of ENaC by aldosterone, and AQP2 by arginine vasopressin (AVP) in principal cells is essential for the control of plasma Na(+) and K(+) concentrations, extracellular fluid volume, and BP. In addition to these essential hormones, additional neuronal, physical, and chemical factors influence Na(+), K(+), and water homeostasis. Notably, a variety of secreted paracrine and autocrine agents such as bradykinin, ATP, endothelin, nitric oxide, and prostaglandin E2 counterbalance and limit the natriferic effects of aldosterone and the water-retaining effects of AVP. Considerable recent progress has improved our understanding of the transporters, receptors, second messengers, and signaling events that mediate principal cell responses to changing environments in health and disease. This review primarily addresses the structure and function of the key transporters and the complex interplay of regulatory factors that modulate principal cell ion and water transport.

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TL;DR: Downregulation of cAMP-dependent PKA/ERK1/2/Elk-1 phosphorylation (by activation of H3R) is important in the inhibition of cholangiocyte growth in liver diseases.
Abstract: Histamine regulates many functions by binding to four histamine G-coupled receptor proteins (H1R, H2R, H3R and H4R) As H3R exerts their effects by coupling to Gαi/o proteins reducing adenosine 3′, 5′-monophosphate (cAMP) levels (a key player in the modulation of cholangiocyte hyperplasia/damage), we evaluated the role of H3R in the regulation of biliary growth We posed the following questions: (1) Do cholangiocytes express H3R? (2) Does in vivo administration of (R)-(α)-(−)-methylhistamine dihydrobromide (RAMH) (H3R agonist), thioperamide maleate (H3R antagonist) or histamine, in the absence/presence of thioperamide maleate, to bile duct ligated (BDL) rats regulate cholangiocyte proliferation? and (3) Does RAMH inhibit cholangiocyte proliferation by downregulation of cAMP-dependent phosphorylation of protein kinase A (PKA)/extracellular signal-regulated kinase 1/2 (ERK1/2)/ets-like gene-1 (Elk-1)? The expression of H3R was evaluated in liver sections by immunohistochemistry and immunofluorescence, and by real-time PCR in cholangiocyte RNA from normal and BDL rats BDL rats (immediately after BDL) were treated daily with RAMH, thioperamide maleate or histamine in the absence/presence of thioperamide maleate for 1 week Following in vivo treatment of BDL rats with RAMH for 1 week, and in vitro stimulation of BDL cholangiocytes with RAMH, we evaluated cholangiocyte proliferation, cAMP levels and PKA, ERK1/2 and Elk-1 phosphorylation Cholangiocytes from normal and BDL rats express H3R The expression of H3R mRNA increased in BDL compared to normal cholangiocytes Histamine decreased cholangiocyte growth of BDL rats to a lower extent than that observed in BDL RAMH-treated rats; histamine-induced inhibition of cholangiocyte growth was partly blocked by thioperamide maleate In BDL rats treated with thioperamide maleate, cholangiocyte hyperplasia was slightly higher than that of BDL rats In vitro, RAMH inhibited the proliferation of BDL cholangiocytes RAMH inhibition of cholangiocyte growth was associated with decreased cAMP levels and PKA/ERK1/2/Elk-1 phosphorylation Downregulation of cAMP-dependent PKA/ERK1/2/Elk-1 phosphorylation (by activation of H3R) is important in the inhibition of cholangiocyte growth in liver diseases

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TL;DR: A member of the Gi family, most likely Gi3, is involved in the cAMP-triggered targeting of AQP2-bearing vesicles to the apical membrane of kidney epithelial cells.
Abstract: Vasopressin is the key regulator of water homeostasis in vertebrates. Central to its antidiuretic action in mammals is the redistribution of the water channel aquaporin 2 (AQP2) from intracellular vesicles to the apical membrane of kidney epithelial cells, an event initiated by an increase in cAMP and activation of protein kinase A. The subsequent steps of the signaling cascade are not known. To identify proteins involved in the AQP2 shuttle we exploited a recently developed cell line (CD8) derived from the rabbit cortical collecting duct and stably transfected with rat AQP2 cDNA. Treatment of CD8 cells with pertussis toxin (PTX) inhibited both the vasopressin-induced increase in water permeability and the redistribution of AQP2 from an intracellular compartment to the apical membrane. ADP-ribosylation studies revealed the presence of at least two major PTX substrates. Correspondingly, two α subunits of PTX-sensitive G proteins, Gαi2 and Gαi3, were identified by Western blotting. Introduction of a synthetic peptide corresponding to the C terminus of the Gi3 α subunit into permeabilized CD8 cells efficiently inhibited the cAMP-induced AQP2 translocation; a peptide corresponding to the α subunits of Gi1/2 was much less potent. Thus a member of the Gi family, most likely Gi3, is involved in the cAMP-triggered targeting of AQP2-bearing vesicles to the apical membrane of kidney epithelial cells.

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TL;DR: Using a hydrodynamic theory describing transport of macromolecules through an isoporous membrane, it was showed that histamine did not affect glomerular pore size but did produce a major reduction in the ratio of pore area:pore length, a measure of por density, which suggests that the fall in K0 is due largely to a functional reduction in total filtration surface area.
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TL;DR: Cell surface biotinylation experiments confirmed that AQP4 is internalized after 20 min of histamine exposure, which may account for the downregulation of water transport, the first evidence for short term rearrangement of OAPs in an established AQP 4-expressing cell line.
Abstract: To test the involvement of the water channel aquaporin (AQP)-4 in gastric acid physiology, the human gastric cell line (HGT)-1 was stably transfected with rat AQP4. AQP4 was immunolocalized to the basolateral membrane of transfected HGT-1 cells, like in native parietal cells. Expression of AQP4 in transfected cells increased the osmotic water permeability coefficient (Pf) from 2.02 +/- 0.3 x 10-4 to 16.37 +/- 0.5 x 10-4 cm/s at 20 degrees C. Freeze-fracture EM showed distinct orthogonal arrays of particles (OAPs), the morphological signature of AQP4, on the plasma membrane of AQP4-expressing cells. Quantitative morphometry showed that the density of OAPs was 2.5 +/- 0.3% under basal condition and decreased by 50% to 1.2 +/- 0.3% after 20 min of histamine stimulation, mainly due to a significant decrease of the OAPs number. Concomitantly, Pf decreased by approximately 35% in 20-min histamine-stimulated cells. Both Pf and OAPs density were not modified after 10 min of histamine exposure, time at which the maximal hormonal response is observed. Cell surface biotinylation experiments confirmed that AQP4 is internalized after 20 min of histamine exposure, which may account for the downregulation of water transport. This is the first evidence for short term rearrangement of OAPs in an established AQP4-expressing cell line.

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Frequently Asked Questions (1)
Q1. What are the contributions in this paper?

In this paper, the presence of the histamine H4 receptor ( H4R ) in resident renal cells of the loop of Henlé and its profound upregulation in the kidney of diabetic rats was investigated.