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Alvira-Iraizoz F, Gillard BT, Lin P, Paterson A, Pauža AG, Ali MA, Alabsi AH, Burger PA, Hamadi N, Adem A, Murphy D, Greenwood MP. Multiomic analysis of the Arabian camel (Camelus dromedarius) kidney reveals a role for cholesterol in water conservation. Commun Biol 2021; 4:779. [PMID: 34163009 PMCID: PMC8222267 DOI: 10.1038/s42003-021-02327-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 06/06/2021] [Indexed: 02/05/2023] Open
Abstract
The Arabian camel (Camelus dromedarius) is the most important livestock animal in arid and semi-arid regions and provides basic necessities to millions of people. In the current context of climate change, there is renewed interest in the mechanisms that enable camelids to survive in arid conditions. Recent investigations described genomic signatures revealing evolutionary adaptations to desert environments. We now present a comprehensive catalogue of the transcriptomes and proteomes of the dromedary kidney and describe how gene expression is modulated as a consequence of chronic dehydration and acute rehydration. Our analyses suggested an enrichment of the cholesterol biosynthetic process and an overrepresentation of categories related to ion transport. Thus, we further validated differentially expressed genes with known roles in water conservation which are affected by changes in cholesterol levels. Our datasets suggest that suppression of cholesterol biosynthesis may facilitate water retention in the kidney by indirectly facilitating the AQP2-mediated water reabsorption.
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Affiliation(s)
- Fernando Alvira-Iraizoz
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, University of Bristol, Bristol, UK.
| | - Benjamin T Gillard
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, University of Bristol, Bristol, UK
| | - Panjiao Lin
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, University of Bristol, Bristol, UK
| | - Alex Paterson
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, University of Bristol, Bristol, UK
| | - Audrys G Pauža
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, University of Bristol, Bristol, UK
| | - Mahmoud A Ali
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, AL Ain, United Arab Emirates
| | - Ammar H Alabsi
- College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Pamela A Burger
- Department of Interdisciplinary Life Sciences, Research Institute of Wildlife Ecology, Vetmeduni Vienna, Vienna, Austria
| | - Naserddine Hamadi
- Department of Life and Environmental Sciences, College of Natural and Health Sciences, Zayed University, Abu Dhabi, United Arab Emirates
| | - Abdu Adem
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, AL Ain, United Arab Emirates.
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates.
| | - David Murphy
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, University of Bristol, Bristol, UK
| | - Michael P Greenwood
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, University of Bristol, Bristol, UK
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Colella JP, Tigano A, Dudchenko O, Omer AD, Khan R, Bochkov ID, Aiden EL, MacManes MD. Limited Evidence for Parallel Evolution Among Desert-Adapted Peromyscus Deer Mice. J Hered 2021; 112:286-302. [PMID: 33686424 PMCID: PMC8141686 DOI: 10.1093/jhered/esab009] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 02/27/2021] [Indexed: 01/14/2023] Open
Abstract
Warming climate and increasing desertification urge the identification of genes involved in heat and dehydration tolerance to better inform and target biodiversity conservation efforts. Comparisons among extant desert-adapted species can highlight parallel or convergent patterns of genome evolution through the identification of shared signatures of selection. We generate a chromosome-level genome assembly for the canyon mouse (Peromyscus crinitus) and test for a signature of parallel evolution by comparing signatures of selective sweeps across population-level genomic resequencing data from another congeneric desert specialist (Peromyscus eremicus) and a widely distributed habitat generalist (Peromyscus maniculatus), that may be locally adapted to arid conditions. We identify few shared candidate loci involved in desert adaptation and do not find support for a shared pattern of parallel evolution. Instead, we hypothesize divergent molecular mechanisms of desert adaptation among deer mice, potentially tied to species-specific historical demography, which may limit or enhance adaptation. We identify a number of candidate loci experiencing selective sweeps in the P. crinitus genome that are implicated in osmoregulation (Trypsin, Prostasin) and metabolic tuning (Kallikrein, eIF2-alpha kinase GCN2, APPL1/2), which may be important for accommodating hot and dry environmental conditions.
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Affiliation(s)
- Jocelyn P Colella
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH.,Hubbard Genome Center, University of New Hampshire, Durham, NH.,Biodiversity Institute, University of Kansas, Lawrence, KS
| | - Anna Tigano
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH.,Hubbard Genome Center, University of New Hampshire, Durham, NH
| | - Olga Dudchenko
- Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Center for Theoretical and Biological Physics, Rice University, Houston, TX.,Department of Computer Science, Department of Computational and Applied Mathematics, Rice University, Houston, TX
| | - Arina D Omer
- Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX
| | - Ruqayya Khan
- Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Department of Computer Science, Department of Computational and Applied Mathematics, Rice University, Houston, TX
| | - Ivan D Bochkov
- Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Department of Computer Science, Department of Computational and Applied Mathematics, Rice University, Houston, TX
| | - Erez L Aiden
- Center for Genome Architecture, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX.,Center for Theoretical and Biological Physics, Rice University, Houston, TX.,Department of Computer Science, Department of Computational and Applied Mathematics, Rice University, Houston, TX.,Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, Shanghai 201210, China.,School of Agriculture and Environment, University of Western Australia, Perth, WA, Australia
| | - Matthew D MacManes
- Department of Molecular, Cellular, and Biomedical Sciences, University of New Hampshire, Durham, NH.,Hubbard Genome Center, University of New Hampshire, Durham, NH
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Nawata CM, Pannabecker TL. Mammalian urine concentration: a review of renal medullary architecture and membrane transporters. J Comp Physiol B 2018; 188:899-918. [PMID: 29797052 PMCID: PMC6186196 DOI: 10.1007/s00360-018-1164-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 04/23/2018] [Accepted: 05/14/2018] [Indexed: 01/10/2023]
Abstract
Mammalian kidneys play an essential role in balancing internal water and salt concentrations. When water needs to be conserved, the renal medulla produces concentrated urine. Central to this process of urine concentration is an osmotic gradient that increases from the corticomedullary boundary to the inner medullary tip. How this gradient is generated and maintained has been the subject of study since the 1940s. While it is generally accepted that the outer medulla contributes to the gradient by means of an active process involving countercurrent multiplication, the source of the gradient in the inner medulla is unclear. The last two decades have witnessed advances in our understanding of the urine-concentrating mechanism. Details of medullary architecture and permeability properties of the tubules and vessels suggest that the functional and anatomic relationships of these structures may contribute to the osmotic gradient necessary to concentrate urine. Additionally, we are learning more about the membrane transporters involved and their regulatory mechanisms. The role of medullary architecture and membrane transporters in the mammalian urine-concentrating mechanism are the focus of this review.
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Affiliation(s)
- C Michele Nawata
- Department of Physiology, Banner University Medical Center, University of Arizona, 1501 N. Campbell Avenue, Tucson, AZ, 85724-5051, USA.
| | - Thomas L Pannabecker
- Department of Physiology, Banner University Medical Center, University of Arizona, 1501 N. Campbell Avenue, Tucson, AZ, 85724-5051, USA
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4
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Aw M, Armstrong TM, Nawata CM, Bodine SN, Oh JJ, Wei G, Evans KK, Shahidullah M, Rieg T, Pannabecker TL. Body mass-specific Na +-K +-ATPase activity in the medullary thick ascending limb: implications for species-dependent urine concentrating mechanisms. Am J Physiol Regul Integr Comp Physiol 2018; 314:R563-R573. [PMID: 29351422 DOI: 10.1152/ajpregu.00289.2017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In general, the mammalian whole body mass-specific metabolic rate correlates positively with maximal urine concentration (Umax) irrespective of whether or not the species have adapted to arid or mesic habitat. Accordingly, we hypothesized that the thick ascending limb (TAL) of a rodent with markedly higher whole body mass-specific metabolism than rat exhibits a substantially higher TAL metabolic rate as estimated by Na+-K+-ATPase activity and Na+-K+-ATPase α1-gene and protein expression. The kangaroo rat inner stripe of the outer medulla exhibits significantly higher mean Na+-K+-ATPase activity (~70%) compared with two rat strains (Sprague-Dawley and Munich-Wistar), extending prior studies showing rat activity exceeds rabbit. Furthermore, higher expression of Na+-K+-ATPase α1-protein (~4- to 6-fold) and mRNA (~13-fold) and higher TAL mitochondrial volume density (~20%) occur in the kangaroo rat compared with both rat strains. Rat TAL Na+-K+-ATPase α1-protein expression is relatively unaffected by body hydration status or, shown previously, by dietary Na+, arguing against confounding effects from two unavoidably dissimilar diets: grain-based diet without water (kangaroo rat) or grain-based diet with water (rat). We conclude that higher TAL Na+-K+-ATPase activity contributes to relationships between whole body mass-specific metabolic rate and high Umax. More vigorous TAL Na+-K+-ATPase activity in kangaroo rat than rat may contribute to its steeper Na+ and urea axial concentration gradients, adding support to a revised model of the urine concentrating mechanism, which hypothesizes a leading role for vigorous active transport of NaCl, rather than countercurrent multiplication, in generating the outer medullary axial osmotic gradient.
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Affiliation(s)
- Mun Aw
- Department of Physiology, Banner-University Medical Center, University of Arizona , Tucson, Arizona
| | - Tamara M Armstrong
- Department of Physiology, Banner-University Medical Center, University of Arizona , Tucson, Arizona
| | - C Michele Nawata
- Department of Physiology, Banner-University Medical Center, University of Arizona , Tucson, Arizona
| | - Sarah N Bodine
- Department of Physiology, Banner-University Medical Center, University of Arizona , Tucson, Arizona
| | - Jeeeun J Oh
- Department of Physiology, Banner-University Medical Center, University of Arizona , Tucson, Arizona
| | - Guojun Wei
- Department of Physiology, Banner-University Medical Center, University of Arizona , Tucson, Arizona
| | - Kristen K Evans
- Department of Physiology, Banner-University Medical Center, University of Arizona , Tucson, Arizona
| | - Mohammad Shahidullah
- Department of Physiology, Banner-University Medical Center, University of Arizona , Tucson, Arizona
| | - Timo Rieg
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida , Tampa, Florida
| | - Thomas L Pannabecker
- Department of Physiology, Banner-University Medical Center, University of Arizona , Tucson, Arizona
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5
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Wei G, Rosen S, Dantzler WH, Pannabecker TL. Architecture of the human renal inner medulla and functional implications. Am J Physiol Renal Physiol 2015; 309:F627-37. [PMID: 26290371 DOI: 10.1152/ajprenal.00236.2015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 08/10/2015] [Indexed: 11/22/2022] Open
Abstract
The architecture of the inner stripe of the outer medulla of the human kidney has long been known to exhibit distinctive configurations; however, inner medullary architecture remains poorly defined. Using immunohistochemistry with segment-specific antibodies for membrane fluid and solute transporters and other proteins, we identified a number of distinctive functional features of human inner medulla. In the outer inner medulla, aquaporin-1 (AQP1)-positive long-loop descending thin limbs (DTLs) lie alongside descending and ascending vasa recta (DVR, AVR) within vascular bundles. These vascular bundles are continuations of outer medullary vascular bundles. Bundles containing DTLs and vasa recta lie at the margins of coalescing collecting duct (CD) clusters, thereby forming two regions, the vascular bundle region and the CD cluster region. Although AQP1 and urea transporter UT-B are abundantly expressed in long-loop DTLs and DVR, respectively, their expression declines with depth below the outer medulla. Transcellular water and urea fluxes likely decline in these segments at progressively deeper levels. Smooth muscle myosin heavy chain protein is also expressed in DVR of the inner stripe and the upper inner medulla, but is sparsely expressed at deeper inner medullary levels. In rodent inner medulla, fenestrated capillaries abut CDs along their entire length, paralleling ascending thin limbs (ATLs), forming distinct compartments (interstitial nodal spaces; INSs); however, in humans this architecture rarely occurs. Thus INSs are relatively infrequent in the human inner medulla, unlike in the rodent where they are abundant. UT-B is expressed within the papillary epithelium of the lower inner medulla, indicating a transcellular pathway for urea across this epithelium.
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Affiliation(s)
- Guojun Wei
- Department of Physiology, University of Arizona Health Sciences Center, Tucson, Arizona; and
| | - Seymour Rosen
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - William H Dantzler
- Department of Physiology, University of Arizona Health Sciences Center, Tucson, Arizona; and
| | - Thomas L Pannabecker
- Department of Physiology, University of Arizona Health Sciences Center, Tucson, Arizona; and
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Abstract
Desert rodents face a sizeable challenge in maintaining salt and water homeostasis due to their life in an arid environment. A number of their organ systems exhibit functional characteristics that limit water loss above that which occurs in non-desert species under similar conditions. These systems include renal, pulmonary, gastrointestinal, nasal, and skin epithelia. The desert rodent kidney preserves body water by producing a highly concentrated urine that reaches a maximum osmolality nearly three times that of the common laboratory rat. The precise mechanism by which urine is concentrated in any mammal is unknown. Insights into the process may be more apparent in species that produce highly concentrated urine. Aquaporin water channels play a fundamental role in water transport in several desert rodent organ systems. The role of aquaporins in facilitating highly effective water preservation in desert rodents is only beginning to be explored. The organ systems of desert rodents and their associated AQPs are described.
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Affiliation(s)
- Thomas L Pannabecker
- Department of Physiology, AHSC 4128, University of Arizona Health Sciences Center, 1501 N. Campbell Avenue, Tucson, Arizona 85724-5051
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7
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Marra NJ, DeWoody JA. Transcriptomic characterization of the immunogenetic repertoires of heteromyid rodents. BMC Genomics 2014; 15:929. [PMID: 25341737 PMCID: PMC4216838 DOI: 10.1186/1471-2164-15-929] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 10/16/2014] [Indexed: 11/18/2022] Open
Abstract
Background When populations evolve under disparate environmental conditions, they experience different selective pressures that shape patterns of sequence evolution and gene expression. These may be manifested in genetic and phenotypic differences such as a diverse immunogenetic repertoire in species from tropical latitudes that have greater and/or different parasite burdens than more temperate species. To test this idea, we compared the transcriptomes of one tropical species (Heteromys desmarestianus) and two species from temperate latitudes (Dipodomys spectabilis and Chaetodipus baileyi) from the Heteromyidae. We did so in a search for positive selection on sequences and/or differential expression, while controlling for phylogenetic history in our choice of species. Results We identified 127,812 contigs and annotated 34,878 of these, identifying immune genes associated with interleukins, cytokines, and the production of mast cells. We identified 632 genes that were upregulated in H. desmarestianus (8.7% of genes tested) and 492 (6.7%) that were downregulated. Gene ontology terms including “immune response” were associated with 31 (4.9%) of the 632 upregulated genes. We found preliminary evidence for positive selection on three genes (Palmitoyltransferase ZDHHC5 Ubiquitin-conjugating enzyme E2 N, Krueppel-like factor 10, and Spindle and kinetochore-associated protein 1) along the H. desmarestianus lineage. Conclusions Overall our findings pinpoint genes in species from disparate environments that are on different evolutionary trajectories in terms of expression levels and/or nucleotide sequence. Our data indicate there are significant differences in the expression of genes among the spleen transcriptomes of these species and that a number of these differentially expressed genes do not show the same pattern of differential expression in another tissue type. This points to the possibility of expression differences between these species specific to the spleen transcriptome. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-929) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nicholas J Marra
- Department of Population Medicine and Diagnostic Sciences, Cornell University, S3-111 Schurman Hall, Tower Road, Ithaca, NY 14853, USA.
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Pannabecker TL, Layton AT. Targeted delivery of solutes and oxygen in the renal medulla: role of microvessel architecture. Am J Physiol Renal Physiol 2014; 307:F649-55. [PMID: 25056344 DOI: 10.1152/ajprenal.00276.2014] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Renal medullary function is characterized by corticopapillary concentration gradients of various molecules. One example is the generally decreasing axial gradient in oxygen tension (Po2). Another example, found in animals in the antidiuretic state, is a generally increasing axial solute gradient, consisting mostly of NaCl and urea. This osmolality gradient, which plays a principal role in the urine concentrating mechanism, is generally considered to involve countercurrent multiplication and countercurrent exchange, although the underlying mechanism is not fully understood. Radial oxygen and solute gradients in the transverse dimension of the medullary parenchyma have been hypothesized to occur, although strong experimental evidence in support of these gradients remains lacking. This review considers anatomic features of the renal medulla that may impact the formation and maintenance of oxygen and solute gradients. A better understanding of medullary architecture is essential for more clearly defining the compartment-to-compartment flows taken by fluid and molecules that are important in producing axial and radial gradients. Preferential interactions between nephron and vascular segments provide clues as to how tubular and interstitial oxygen flows contribute to safeguarding active transport pathways in renal function in health and disease.
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Affiliation(s)
- Thomas L Pannabecker
- Department of Physiology, College of Medicine, University of Arizona, Tucson, Arizona; and
| | - Anita T Layton
- Department of Mathematics, Duke University, Durham, North Carolina
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Gilbert RL, Pannabecker TL. Architecture of interstitial nodal spaces in the rodent renal inner medulla. Am J Physiol Renal Physiol 2013; 305:F745-52. [PMID: 23825077 DOI: 10.1152/ajprenal.00239.2013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Every collecting duct (CD) of the rat inner medulla is uniformly surrounded by about four abutting ascending vasa recta (AVR) running parallel to it. One or two ascending thin limbs (ATLs) lie between and parallel to each abutting AVR pair, opposite the CD. These structures form boundaries of axially running interstitial compartments. Viewed in transverse sections, these compartments appear as four interstitial nodal spaces (INSs) positioned symmetrically around each CD. The axially running compartments are segmented by interstitial cells spaced at regular intervals. The pairing of ATLs and CDs bounded by an abundant supply of AVR carrying reabsorbed water, NaCl, and urea make a strong argument that the mixing of NaCl and urea within the INSs and countercurrent flows play a critical role in generating the inner medullary osmotic gradient. The results of this study fully support that hypothesis. We quantified interactions of all structures comprising INSs along the corticopapillary axis for two rodent species, the Munich-Wistar rat and the kangaroo rat. The results showed remarkable similarities in the configurations of INSs, suggesting that the structural arrangement of INSs is a highly conserved architecture that plays a fundamental role in renal function. The number density of INSs along the corticopapillary axis directly correlated with a loop population that declines exponentially with distance below the outer medullary-inner medullary boundary. The axial configurations were consistent with discrete association between near-bend loop segments and INSs and with upper loop segments lying distant from INSs.
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Affiliation(s)
- Rebecca L Gilbert
- Dept. of Physiology, Univ. of Arizona Health Sciences Center, AHSC 4128, 1501 N. Campbell Ave., Tucson, AZ 85724-5051, USA
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Sendeski MM, Liu ZZ, Perlewitz A, Busch JF, Ikromov O, Weikert S, Persson PB, Patzak A. Functional characterization of isolated, perfused outermedullary descending human vasa recta. Acta Physiol (Oxf) 2013; 208:50-6. [PMID: 23414239 DOI: 10.1111/apha.12084] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 02/07/2013] [Accepted: 02/11/2013] [Indexed: 01/28/2023]
Abstract
AIM The renal medulla plays an important role in the control of water and salt balance by the kidney. Outer medullary descending vasa recta (OMDVR) are microscopic vessels providing blood flow to the renal medulla. Data on the physiology of human vasa recta are scarce. Therefore, we established an experimental model of human single isolated, perfused OMDVR and characterized their vasoactivity in response to angiotensin II and to pressure changes. METHODS Human non-malignant renal tissue was obtained from patients undergoing nephrectomy due to renal cell carcinoma. OMDVR were dissected under magnification and perfused using concentric microscopic pipettes. The response of OMDVR to angiotensin II and pressure changes was quantified in serial pictures. All patients signed a consent form prior to surgery. RESULTS Outer medullary descending vasa recta constricted significantly after bolus applications of angiotensin II. OMDVR constriction to angiotensin II was also concentration dependent. Response to luminal pressure changes was different according to the diameter of vessels, with larger OMDVR constricting after pressure increase, while smaller ones did not. CONCLUSION Outer medullary descending vasa recta constrict in response to angiotensin II and pressure increases. Our results show that OMDVR may take part in the regulation of medullary blood flow in humans. Our model may be suitable for investigating disturbances of renal medullary circulation in human subjects.
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Affiliation(s)
- M. M. Sendeski
- Institut für Vegetative Physiologie; Charité - Universitätsmedizin Berlin; Berlin; Germany
| | - Z. Z. Liu
- Institut für Vegetative Physiologie; Charité - Universitätsmedizin Berlin; Berlin; Germany
| | - A. Perlewitz
- Institut für Vegetative Physiologie; Charité - Universitätsmedizin Berlin; Berlin; Germany
| | - J. F. Busch
- Klinik für Urologie; Charité Universitätsmedizin-Berlin; Berlin; Germany
| | - O. Ikromov
- Klinik für Urologie; Charité Universitätsmedizin-Berlin; Berlin; Germany
| | - S. Weikert
- Klinik für Urologie; Charité Universitätsmedizin-Berlin; Berlin; Germany
| | - P. B. Persson
- Institut für Vegetative Physiologie; Charité - Universitätsmedizin Berlin; Berlin; Germany
| | - A. Patzak
- Institut für Vegetative Physiologie; Charité - Universitätsmedizin Berlin; Berlin; Germany
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Pannabecker TL. Comparative physiology and architecture associated with the mammalian urine concentrating mechanism: role of inner medullary water and urea transport pathways in the rodent medulla. Am J Physiol Regul Integr Comp Physiol 2013; 304:R488-503. [PMID: 23364530 PMCID: PMC3627947 DOI: 10.1152/ajpregu.00456.2012] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 01/25/2013] [Indexed: 01/07/2023]
Abstract
Comparative studies of renal structure and function have potential to provide insights into the urine-concentrating mechanism of the mammalian kidney. This review focuses on the tubular transport pathways for water and urea that play key roles in fluid and solute movements between various compartments of the rodent renal inner medulla. Information on aquaporin water channel and urea transporter expression has increased our understanding of functional segmentation of medullary thin limbs of Henle's loops, collecting ducts, and vasa recta. A more complete understanding of membrane transporters and medullary architecture has identified new and potentially significant interactions between these structures and the interstitium. These interactions are now being introduced into our concept of how the inner medullary urine-concentrating mechanism works. A variety of regulatory pathways lead directly or indirectly to variable patterns of fluid and solute movements among the interstitial and tissue compartments. Animals with the ability to produce highly concentrated urine, such as desert species, are considered to exemplify tubular structure and function that optimize urine concentration. These species may provide unique insights into the urine-concentrating process.(1)
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Affiliation(s)
- Thomas L Pannabecker
- Department of Physiology, AHSC 4128, University of Arizona Health Sciences Center, 1501 N. Campbell Ave., Tucson, AZ 85724-5051, USA.
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