Angiotensin II receptors: Localization of type I and type II in rat epididymides of different developmental stages

1. Angiotensin II receptors on platelets were studied in 13 patients with uncomplicated type I diabetes mellitus and in 15 age-matched normal subjects. 2. Receptor density on cells from the diabetic patients was 15% lower than the normal subjects (5.2 ± 0.8 sd sites/platelet in diabetic patients and 6.4 ± 0.8 in normals, P < 0.001), but there were no differences in receptor affinity as measured by Kd (4.9 ± 1.5 × 10−10 mol/l in diabetic patients and 5.4 ± 1.4 × 10−10 mol/l in normals). 3. Plasma concentrations of renin and angiotensin II were similar in both groups. 4. The reduced density of angiotensin II receptors on platelets from patients with insulin-dependent diabetes may reflect a generalized abnormality of angiotensin II receptor regulation.

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Cardiac angiotensin II type I and type II receptors are increased in rats submitted to experimental hypothyroidism

The Journal of Physiology ◽

10.1113/jphysiol.2007.134080 ◽

2007 ◽

Vol 583 (1) ◽

pp. 213-223 ◽

Cited By ~ 22

Author(s):

M. S. Carneiro-Ramos ◽

G. P. Diniz ◽

J. Almeida ◽

R. L. P. Vieira ◽

S. V. B. Pinheiro ◽

...

Keyword(s):

Angiotensin Ii ◽

Type I ◽

Type Ii

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Expression of intermediate filament proteins during development of Xenopus laevis. III. Identification of mRNAs encoding cytokeratins typical of complex epithelia

Development ◽

10.1242/dev.104.4.533 ◽

1988 ◽

Vol 104 (4) ◽

pp. 533-548 ◽

Cited By ~ 1

Author(s):

B. Fouquet ◽

H. Herrmann ◽

J.K. Franz ◽

W.W. Franke

Keyword(s):

Xenopus Laevis ◽

Developmental Stages ◽

Type I ◽

Type Ii ◽

S1 Nuclease ◽

Intermediate Filament Proteins ◽

Larval Stages ◽

Adult Tissues ◽

Adult Organism ◽

Restricted Pattern

A Xenopus laevis mRNA encoding a cytokeratin of the basic (type II) subfamily that is expressed in postgastrulation embryos was cDNA-cloned and sequenced. Comparison of the deduced amino acid sequence of this polypeptide (513 residues, calculated mol. wt 55,454; Mr approximately 58,000 on SDS-PAGE) with those of other cytokeratins revealed its relationship to certain type II cytokeratins of the same and other species, but also remarkable differences. Using a subclone representing the 3′-untranslated portion of the 2.4 kb mRNA encoding this cytokeratin, designated XenCK55(5/6), in Northern blot experiments, we found that it differs from the only other Xenopus type II cytokeratin known, i.e. the simple epithelium-type component XenCK1(8), in that it is absent in unfertilized eggs and pregastrulation embryos. XenCK55(5/6) mRNA was first detected at gastrulation (stage 11) and found to rapidly increase during neurulation and further development. It was also identified in Xenopus laevis cultured kidney epithelial cells of the line A6 and in the adult animal where it is a major polypeptide in the oesophageal mucosa but absent in most other tissues examined. The pattern of XenCK55(5/6) expression during embryonic development was similar to that reported for the type I polypeptides of the ‘XK81 subfamily’ previously reported to be embryo-specific and absent in adult tissues. Therefore, we used a XK81 mRNA probe representing the 3′-untranslated region in Northern blots, S1 nuclease and hybrid-selection-translation assays and found the approximately 1.6 kb XK81 mRNA and the resulting protein of Mr approximately 48,000 not only in postgastrula embryos and tadpoles but also in the oesophagus of adult animals. Our results show that both these type II and type I cytokeratins are synthesized only on gastrulation and are very actively produced in early developmental stages but is continued in at least one epithelium of the adult organism. These observations raise doubts on the occurrence of Xenopus cytokeratins that are strictly specific for certain embryonic or larval stages and absent in the adult. They rather suggest that embryonically expressed cytokeratins are also produced in some adult tissues, although in a restricted pattern of tissue and cell type distribution.

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Angiotensin II Type II Receptor Deficiency Accelerates the Development of Nephropathy in Type I Diabetes via Oxidative Stress and ACE2

Experimental Diabetes Research ◽

10.1155/2011/521076 ◽

2011 ◽

Vol 2011 ◽

pp. 1-12 ◽

Cited By ~ 36

Author(s):

Shiao-Ying Chang ◽

Yun-Wen Chen ◽

Isabelle Chenier ◽

Stella Le Minh Tran ◽

Shao-Ling Zhang

Keyword(s):

Oxidative Stress ◽

Gene Expression ◽

Angiotensin Ii ◽

Type I Diabetes ◽

Ros Generation ◽

Heme Oxygenase 1 ◽

Protein Accumulation ◽

Type I ◽

Type Ii ◽

Renal Hypertrophy

Since the functional role(s) of angiotensin II (Ang II) type II receptor (AT2R) in type I diabetes is unknown, we hypothesized that AT2R is involved in decreasing the effects of type I diabetes on the kidneys. We induced diabetes with low-dose streptozotocin (STZ) in both AT2R knockout (AT2RKO) and wild-type (WT) male mice aged 12 weeks and followed them for 4 weeks. Three subgroups nondiabetic, diabetic, and insulin-treated diabetic (Rx insulin implant) were studied. Systolic blood pressure (SBP), physiological parameters, glomerular filtration rate (GFR), renal morphology, gene expression, and apoptosis were assessed. After 4 weeks of diabetes, compared to WT controls, AT2RKO mice clearly developed features of early diabetic nephropathy (DN), such as renal hypertrophy, tubular apoptosis, and progressive extracellular matrix (ECM) protein accumulation as well as increased GFR. AT2RKO mice presented hypertension unaffected by diabetes. Renal oxidative stress (measured as heme oxygenase 1 (HO-1) gene expression and reactive oxygen species (ROS) generation) and intrarenal renin angiotensin system components, such as angiotensinogen (Agt), AT1R, and angiotensin-converting enzyme (ACE) gene expression, were augmented whereas angiotensin-converting enzyme2 (ACE2) gene expression was decreased in renal proximal tubules (RPTs) of AT2RKO mice. The renal changes noted above were significantly enhanced in diabetic AT2RKO mice but partially attenuated in insulin-treated diabetic WT and AT2RKO mice. In conclusion, AT2R deficiency accelerates the development of DN, which appears to be mediated, at least in part, via heightened oxidative stress and ACE/ACE2 ratio in RPTs.

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Genome-wide identification, characterization, and transcriptional analysis of the metacaspase gene family in cucumber (Cucumis sativus)

Genome ◽

10.1139/gen-2017-0174 ◽

2018 ◽

Vol 61 (3) ◽

pp. 187-194 ◽

Cited By ~ 5

Author(s):

Yong Zhou ◽

Lifang Hu ◽

Lunwei Jiang ◽

Shiqiang Liu

Keyword(s):

Gene Family ◽

Cucumis Sativus ◽

Stress Responses ◽

Developmental Stages ◽

Expression Patterns ◽

Plant Stress ◽

Transcriptional Analysis ◽

Type I ◽

Type Ii ◽

Motif Analysis

Metacaspase (MC), a family of caspase-like proteins, plays vital roles in regulating programmed cell death (PCD) during development and in response to stresses in plants. In this study, five MC genes (designated as CsMC1 to CsMC5) were identified in the cucumber (Cucumis sativus) genome. Sequence analysis revealed that CsMC1–CsMC3 belong to type I MC proteins, while CsMC4 and CsMC5 are type II MC proteins. Phylogenetic tree and conserved motif analysis of MC proteins indicated that these proteins can be classified into two groups, which are correlated with the types of these MC proteins. Gene structure analysis demonstrated that type I CsMC genes contain 4–7 introns, while all type II CsMC genes harbor one intron. In addition, many hormone-, stress-, and development-related cis-elements were identified in the promoter regions of CsMC genes. Expression analysis using RNA-seq data revealed that CsMC genes have distinct expression patterns in various tissues and developmental stages. qRT-PCR results showed that the transcript levels of CsMC genes could be regulated by various abiotic stresses such as NaCl, PEG, and cold. These results demonstrate that the cucumber MC gene family may function in tissue development and plant stress responses.

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Losartan, an angiotensin type I receptor antagonist, improves conduit vessel endothelial function in Type II diabetes

Clinical Science ◽

10.1042/cs1000013 ◽

2000 ◽

Vol 100 (1) ◽

pp. 13-17 ◽

Cited By ~ 3

Author(s):

Craig CHEETHAM ◽

Gerard O'DRISCOLL ◽

Kim STANTON ◽

Roger TAYLOR ◽

Daniel GREEN

Keyword(s):

Angiotensin Ii ◽

Endothelial Function ◽

Receptor Antagonist ◽

Type Ii Diabetes ◽

Type I ◽

Type Ii ◽

Double Blind ◽

Resistance Vessels ◽

Conduit Vessel

We have demonstrated previously that inhibition of angiotensin-converting enzyme (ACE) with enalapril and angiotensin II blockade with losartan improve acetylcholine-dependent endothelial function in resistance vessels of patients with Type II diabetes. It was therefore of interest to examine the effect of losartan on conduit vessel function in this group. The influence of losartan (50 mg daily for 4 weeks) on endothelium-dependent and -independent vasodilator function was determined in 12 subjects with Type II diabetes using a randomized, double-blind, placebo-controlled crossover protocol. Conduit vessel endothelial function was assessed using high-resolution ultrasound and the brachial artery response to reactive hyperaemia (flow-mediated dilation; FMD); glyceryl trinitrate (GTN) was used as a non-endothelium-dependent dilator. Losartan administration significantly increased the FMD response from 5.2±0.7% (mean±S.E.M.) to 7.4±0.6% of vessel diameter (P < 0.05; paired t-test). There was no effect of losartan on the endothelium-independent responses to GTN (17.8±1.8% to 17.6±1.2%). Consistent with our previous findings in resistance vessels, administration of 50 mg of losartan daily improves NO-mediated dilation in the conduit vessels of subjects with Type II diabetes. Together with the findings that both ACE inhibition and angiotensin II blockade improve resistance vessel function in this group, it is likely that at least some of the beneficial effect is mediated through the angiotensin II/type 1 receptor pathway. A type 1 receptor antagonist seems a reasonable alternative to an ACE inhibitor to maintain conduit vessel endothelial function in Type II diabetic subjects.

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