Interstitial Tissue Compliance in the Genesis of Hypertension

Author(s):  
M. A. Floyer ◽  
J. Lucas ◽  
D. V. Morris
1974 ◽  
Vol 47 (1) ◽  
pp. 1-11 ◽  
Author(s):  
J. Lucas ◽  
M. A. Floyer

1. To determine the part played by changes in interstitial tissue compliance in the mechanism of experimental renal hypertension, pressure and volume measurements were made in rats 60 days after partial constriction of one renal artery with a clip and removal of the opposite kidney. Tissue pressure and venous pressure were found to be significantly higher in rats which developed systolic arterial blood pressure of 140 mmHg or above than in loosely clipped controls with normal blood pressure. Plasma volume (PV) was also increased in the hypertensive animals, but there was no difference in interstitial fluid volume (IFV); the PV/IFV ratio was significantly higher in the hypertensive rats. 2. Removal of the clip in the hypertensive rats restored blood pressure to normal in 1 h; this was associated with a fall in venous pressure and plasma volume. Tissue pressure fell despite a rise in interstitial fluid volume; the PV/IFV ratio fell. 3. It is suggested that renal artery constriction, possibly by a humoral mechanism, causes a fall in interstitial space compliance and that this, by causing changes in body fluid distribution, plays a part in the mechanism of experimental renal hypertension. This mechanism may have a physiological role in the maintenance of adequate plasma volume during water shortage.


1963 ◽  
Vol 43 (4) ◽  
pp. 561-570 ◽  
Author(s):  
Gösta Bengtsson ◽  
Sven Ullberg

ABSTRACT The distribution in mice of 14C- and 3H-diethylstilboestrol has been investigated autoradiographically. The results have been compared with those which have been previously reported for natural oestrogens. Many similarities have been demonstrated between the synthetic and natural compounds. Thus a specific accumulation has been observed in the endometrium, the granulosa layer of large ovarian follicles, the adrenal cortex. the interstitial tissue of the testes, and the hypophysis. Natural and synthetic oestrogens differ widely concerning the penetration into and the distribution within the foetus.


1987 ◽  
Vol 116 (3_Suppl) ◽  
pp. S1
Author(s):  
R. MELSERT ◽  
G. H. DRETELER ◽  
F. F. G. ROMMERTS

2020 ◽  
Vol 26 (35) ◽  
pp. 4515-4521
Author(s):  
Francisco J. López-Iranzo ◽  
Ana M. López-Rodas ◽  
Luis Franco ◽  
Gerardo López-Rodas

Background: COVID-19, caused by SARS-CoV-2, is a potentially lethal, rapidly-expanding pandemic and many efforts are being carried out worldwide to understand and control the disease. COVID-19 patients may display a cytokine release syndrome, which causes severe lung inflammation, leading, in many instances, to death. Objective: This paper is intended to explore the possibilities of controlling the COVID-19-associated hyperinflammation by using licensed drugs with anti-inflammatory effects. Hypothesis: We have previously described that pentoxifylline alone, or in combination with oxypurinol, reduces the systemic inflammation caused by experimentally-induced pancreatitis in rats. Pentoxifylline is an inhibitor of TNF-α production and oxypurinol inhibits xanthine oxidase. TNF-α, in turn, activates other inflammatory genes such as Nos2, Icam or IL-6, which regulate migration and infiltration of neutrophils into the pulmonary interstitial tissue, causing injury to the lung parenchyma. In acute pancreatitis, the anti-inflammatory action of pentoxifylline seems to be mediated by the prevention of the rapid and presumably transient loss of PP2A activity. This may also occur in the hyperinflammatory -cytokine releasing phase- of SARS-CoV-2 infection. Therefore, it may be hypothesized that early treatment of COVID-19 patients with pentoxifylline, alone or in combination with oxypurinol, would prevent the potentially lethal acute respiratory distress syndrome. Conclusion: Pentoxifylline and oxypurinol are licensed drugs used for diseases other than COVID-19 and, therefore, phase I clinical trials would not be necessary for the administration to SARS-CoV-2- infected people. It would be worth investigating their potential effects against the hyperinflammatory response to SARS-CoV-2 infection.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 699.1-699
Author(s):  
A. Gil-Vila ◽  
G. Burcet ◽  
A. Anton-Vicente ◽  
D. Gonzalez-Sans ◽  
A. Nuñez-Conde ◽  
...  

Background:Antisynthetase syndrome (ASS) is characterized by inflammatory myopathy, interstitial lung disease, arthritis, mechanical hands and Raynaud phenomenon, among other features. Recent studies have shown that idiopathic inflammatory myopathies (IIM) may develop cardiac involvement, either ischemic (coronary artery disease) or inflammatory (myocarditis). We wonder if characteristic lung interstitial involvement (interstitial lung disease) that appears in patients with the ASS may also affect the myocardial interstitial tissue. New magnetic resonance mapping techniques could detect subclinical myocardial involvement, mainly as edema (increase extracellular volume in interstitium and extracellular matrix), even in the absence of visible late Gadolinium enhancement (LGE).Objectives:Our aim was to describe the presence of interstitial myocarditis in a group of patients with ASS.Methods:Cross-sectional, observational study performed in a tertiary care center. We included 13 patients diagnosed with ASS (7 male, 53%, mean (SD) age at diagnosis 56,8 years (±11,8)). The patients were consecutively selected from our outpatient myositis clinic. Myositis specific and associated antibodies were performed by means of line immunoblot (EUROIMMUN©). Cardiac magnetic resonance (CMR) was performed on all patients. The study protocol includes functional cine magnetic resonance and standard late gadolinium enhancement (LGE), as well as novel parametric T1 and T2 mapping sequences (modified look locker inversion recovery sequences - MOLLI) with extracellular volume (ECV) calculation 20 minutes after the injection of a gadolinium-based contrast material.Results:CMR could not be performed in one patient due to anxiety. All patients studied (12) had a normal biventricular function, without alteration of segmental contraction. A third (4 out of 12, 33%) of the studied patients showed elevated T2 myocardial values without focal LGE, half of them (2/4) with an elevated ECV, consistent with myocardial edema. Two patients with normal T2 values showed unspecific LGE focal patterns, one in the right ventricle union points and another with mild interventricular septum enhancement (Figure 1). None of the patients studied refer any cardiac symptomatology. All the four patients with T2 mapping alterations (100%) had interstitial lung involvement, but only 4 out of 8 (50%) of the rest ASS patients without T2 mapping positivity. The autoimmune profile was as follows: 10 anti-Jo1/Ro52, 1 anti-EJ/Ro52, 2 anti-PL12.Conclusion:Myocarditis, although subclinical, appears to be a feature in ASS patients. T1 and T2 mapping sequences might be valuable to detect and monitor subclinical cardiac involvement in these patients. The possibility that the same etiopathogenic mechanism may be involved in the interstitial tissue in lung and myocardium is raised. More studies must be done in order to assert the prevalence of myocarditis in ASS.References:[1]Dieval C et al. Myocarditis in Patients With Antisynthetase Syndrome: Prevalence, Presentation, and Outcomes. Medicine (Baltimore). 2015 Jul;94(26):e798.[2]Myhr KA, Pecini R. Management of Myocarditis in Myositis: Diagnosis and Treatment. Curr Rheumatol Rep. 2020 Jul 22; 22:49.[3]Sharma K, Orbai AM, Desai D, Cingolani OH, Halushka MK, Christopher-Stine L, Mammen AL, Wu KC, Zakaria S. Brief report: antisynthetase syndrome-associated myocarditis. J Card Fail. 2014 Dec;20(12):939-45.Figure 1.Cardiac magnetic resonance images from ASS patients.Disclosure of Interests:None declared


Author(s):  
Mea Asou ◽  
Tomohiko Asakawa ◽  
Makoto Araki ◽  
Takashi Ehara ◽  
Tsunekazu Hishima ◽  
...  

Extramedullary hematopoiesis is widely known to occur in patients with primary myelofibrosis (PMF). Autopsy studies on individuals with PMF revealed that extramedullary hematopoiesis occurred in the kidneys in 35% of the cases, but there is little awareness regarding such lesions. A 63-year-old man was diagnosed with PMF based on a detailed examination of persistent high white blood cells. An examination of the patient’s medical records revealed an increased white blood cell count, deterioration of kidney function, and urinary protein excretion developed simultaneously. Thus, a kidney biopsy was performed. Advanced lymphocyte invasion was recognized in the interstitial tissue, and the tubular structure was highly disrupted. Based on these findings, he was diagnosed with interstitial nephritis. However, because of the large number of cells with nuclear atypia in the stroma, additional immunohistochemical staining was also performed, such as glycophorin A, naphthol AS-D, myeloperoxidase, and CD42b. As a result, invasion of three lineages of immature cells, erythroblasts, megakaryocytes, and granulocytes, was identified. Renal dysfunction resulting from interstitial cellular infiltration due to extramedullary hematopoiesis was therefore diagnosed. Treatment with ruxolitinib was initiated after a renal biopsy and the rate of decline in renal function was slightly reduced. Although, in myeloproliferative disorders, proliferative glomerular lesions are widely considered to be renal disorders, there is little awareness regarding interstitial lesions. Extramedullary hematopoiesis of the kidney in PMF is not uncommon, but 40% of cases are reportedly misdiagnosed as interstitial nephritis. Because extramedullary hematopoiesis can be controlled by ruxolitinib, early detection is important.


2019 ◽  
Vol 124 ◽  
pp. 6-18 ◽  
Author(s):  
Stephen C. Kanick ◽  
Peter A. Schneider ◽  
Bruce Klitzman ◽  
Natalie A. Wisniewski ◽  
Kerstin Rebrin

1994 ◽  
Vol 116 (2) ◽  
pp. 164-171 ◽  
Author(s):  
P. D. Schreuders ◽  
K. R. Diller ◽  
J. J. Beaman ◽  
H. M. Paynter

A one-dimensional multicomponent kinetic model was developed to simulate the interstitial diffusion of macromolecules in a three component system, consisting of water, the macromolecule and the interstitial matrix. Movement of the individual components was modeled as occurring in finite jumps between discrete low energy wells along paths defined in terms of species occupation. The flow rate was expressed as a function of the local species concentration, the jump distance, and a kinetic frequency parameter. The model, implemented in pseudo-bond graph form, was examined by fitting it to data obtained for the transport of fluorescein tagged dextran to determine the kinetic constants for that specific system.


1913 ◽  
Vol 18 (4) ◽  
pp. 322-346 ◽  
Author(s):  
Frank P. Underhill ◽  
H. Gideon Wells ◽  
Samuel Goldschmidt

Salts of tartaric acid administered subcutaneously to fasting phlorhizinized animals exert a markedly detrimental influence upon the secretory efficiency of the kidney, which is indicated by a greatly lessened output of certain typical urinary constituents. A histological study of the nephritic kidney demonstrates that the salts act specifically upon the epithelium of the convoluted tubules, and to a less extent upon the tubules of the loops of Henle, the glomerules, and interstitial tissue remaining unharmed. In the disintegrative process taking place, vacuolation first occurs, is rapidly followed by necrosis, and finally the dead cells or their debris may entirely fill the lumina of the tubules and form granular and hyaline casts. There is no strict relation between the dose of tartrate and the extent of damage inflicted. While large doses invariably induce a well marked response small doses may at times produce effects equally significant. Tartrates introduced into fasting animals call forth symptoms practically identical with those observed in fasting phlorhinized animals. It is therefore apparent that in the establishment of the pathological condition under discussion phlorhizin is without significant influence. Neither the liver nor the adrenal exhibits any detrimental effect from the injection of tartrates. The introduction of tartrates by way of the mouth to fasting rabbits is not nearly so effective in the production of nephritic symptoms as the administration of much smaller doses subcutaneously. In general, under the former circumstances the initial stages only of epithelial disintegration of the convoluted tubules obtain, which, however, are scarcely sufficient to account for the rapidity with which death usually ensues. Although in well fed animals distinct pathological changes in the kidney are induced by the introduction of tartrates per os, these abnormalities are less in degree, but similar in kind, than those provoked under like conditions in the fasting animal. When tartrates are given subcutaneously to well fed rabbits the effects evoked are somewhat less pronounced than when the salts are injected into fasting animals. From these facts it is evident that the state of nutrition plays a part in the development of tartrate nephritis. It is indicated that the introduction of a sufficiency of alkali to animals in a state of fasting permits a greater elimination of urinary constituents during tartrate nephritis than obtains under similar circumstances when the alkali is omitted. Histologically there is evidence that the administration of alkali exerts a slight modifying action.


Sign in / Sign up

Export Citation Format

Share Document