4 research outputs found
Hepcydyna - hormon w膮trobowy kontroluj膮cy homeostaz臋 偶elaza
Ostatnie 10-lecie przynios艂o znacz膮cy wzrost wiedzy
dotycz膮cej ustrojowej gospodarki 偶elazem, na co
szczeg贸lny wp艂yw mia艂o odkrycie hepcydyny. Hormon
ten, odkryty w 2000 roku, jest produkowanym
w w膮trobie 25-aminokwasowym polipeptydem i powoduje
internalizacj臋 ferroportyny w enterocytach
dwunastnicy, hamuj膮c wch艂anianie 偶elaza w przewodzie
pokarmowym. Z kolei inaktywacja ferroportyny
w makrofagach skutkuje zahamowaniem uwalniania
do krwi kr膮偶膮cej 偶elaza uwolnionego ze sfagocytowanych
erytrocyt贸w. Precyzyjna regulacja st臋偶e艅
hepcydyny ma kluczowe znaczenie dla utrzymania
st臋偶e艅 偶elaza w w膮skim, wymaganym przez ustr贸j,
zakresie. Poza ustrojowymi zasobami 偶elaza na syntez臋
hormonu wp艂ywaj膮 nasilenie erytropoezy i niedotlenienie
organizmu, ale r贸wnie偶 - co ma du偶e
znaczenie w niedokrwisto艣ci stanu zapalnego - cytokiny
prozapalne, zw艂aszcza interleukina 1, interleukina
6 i TNF-α. Oznaczanie st臋偶e艅 hepcydyny
w przysz艂o艣ci mo偶e si臋 sta膰 wa偶nym parametrem
w ca艂o艣ciowej ocenie gospodarki 偶elazowej organizmu,
wp艂ywaj膮c r贸wnie偶 na podejmowane decyzje
terapeutyczne.
Forum Nefrologiczne 2010, tom 3, nr 4, 233-24
Exposure of pregnant rats to cigarette-smoke condensate causes glomerular abnormalities in offspring
Background: Higher blood pressure and albuminuria are found in offspring of mothers who smoke during pregnancy. Whether or not kidney development is affected by maternal smoking is unknown. Methods: Sprague-Dawley rats were randomly allocated to twice-daily cigarette-smoke and nicotine condensate (1 mg/kg) or vehicle at day 10 of pregnancy until delivery. Results: Exposed offspring did not differ from control offspring with respect to body weight, kidney weight, albuminuria, and creatinine clearance. Both male and female offspring had higher tail-plethysmographic blood pressures and lower mean glomerular volume, podocyte, mesangial-cell, and endothelial-cell number, compared to control offspring. Conclusions: The data document that prenatal exposure to cigarette-smoke condensate containing nicotine influences normal kidney development and could predispose to higher blood pressures later in life. Copyright (c) 2012 S. Karger AG, Base
Prevalence and characteristic of adrenal glands’ abnormalities assessed by computed tomography in hypertensive patients with elevated plasma aldosterone to renin activity ratio
Wst臋p Warto艣膰 wsp贸艂czynnika aldosteronowo-reninowego
(ALDO/ARO) wi臋ksza ni偶 50 u chorych na
nadci艣nienie t臋tnicze (w tym r贸wnie偶 u chorych bez
towarzysz膮cej hipokaliemii) jest uznawana przez
wielu badaczy za wystarczaj膮ce kryterium do rozpoznania
pierwotnego hiperaldosteronizmu. Celem
pracy by艂a ocena cz臋sto艣ci wyst臋powania i charakteru
zmian morfologicznych w nadnerczach wykrywanych
przy u偶yciu tomografii komputerowej (CT)
spiralnej u chorych na nadci艣nienie t臋tnicze z podwy偶szonym
(≥ 50) wsp贸艂czynnikiem ALDO/PRA.Materia艂 i metody U 1367 pacjent贸w dwukrotnie
oznaczano aktywno艣膰 reninow膮 osocza (PRA) — po
3 dniach stosowania diety zawieraj膮cej 100–120 mmol
sodu na dob臋 i 8-godzinnym przebywaniu w pozycji
le偶膮cej (PRA1) oraz po kolejnych 3 dniach diety
z ograniczeniem sodu do 10–20 mmol/dob臋 i 3-godzinnej
pionizacji cia艂a (PRA2). St臋偶enie aldosteronu
w osoczu oznaczano tylko u pacjent贸w z niskoreninowym
profilem nadci艣nienia t臋tniczego (PRA1 < 1 ng/ml/h
i PRA2/PRA1 < 1,5 ng/ml/h), r贸wnie偶 dwukrotnie
— przed stymulacj膮 i po stymulacji diet膮 ubogosodow膮
i pionizacj膮 (ALDO1 i ALDO2). U pacjent贸w,
u kt贸rych stwierdzono warto艣ci wsp贸艂czynnika ≥ 50
wykonano badanie CT jamy brzusznej metod膮 spiraln膮
oraz test do偶ylnego obci膮偶enia sol膮.
Wyniki U 36 pacjent贸w stwierdzono warto艣膰 wsp贸艂czynnika
ALDO/PRA ≥ 50 (2,6% wszystkich badanych
chorych na nadci艣nienie t臋tnicze). W tej podgrupie
znamiennie cz臋艣ciej obserwowano hipokaliemi臋
(< 3,5 mmol/l). U 34 pacjent贸w wykonano CT. Najcz臋艣ciej
stwierdzanymi zmianami by艂y: guz i obustronny
przerost nadnerczy. U 44,1% chorych (n = 15) nie
uwidoczniono 偶adnej patologii w obr臋bie gruczo艂贸w
nadnerczowych. U 24 pacjent贸w wykonano test obci膮偶enia
sol膮. Wynik dodatni uzyskano w 15 przypadkach.
Analiza ROC wykaza艂a, 偶e przy warto艣ci wsp贸艂czynnika
powy偶ej 147 zmiany w CT stwierdza si臋 u 66,7%
chorych, a jedynie 21,1% zmian pozostaje niewykrytych.
Wnioski 1. Cz臋sto艣膰 hiperaldosteronizmu pierwotnego
w og贸lnej populacji chorych na nadci艣nienie
t臋tnicze oceniana wy艂膮cznie na podstawie podwy偶szonej
warto艣ci wsp贸艂czynnika ALDO/PRA (≥ 50)
wynosi 2,6%. 2. Wsp贸艂czynnik ALDO/PRA jest
szczeg贸lnie przydatny w rozpoznawaniu zespo艂u
Conna o niewielkim stopniu zaawansowania klinicznego
i bez podwy偶szonego st臋偶enia aldosteronu
w surowicy. 3. Warto艣膰 wsp贸艂czynnika ALDO/PRA
powy偶ej 147 jest charakterystyczna dla chorych ze
zmianami morfologicznymi nadnerczy wykrywanymi
za pomoc膮 CT spiralnej.Background The plasma aldosterone to renin activity
(ALDO/PRA) ratio over 50 in hypertensive patients is
widely recognized as a cut-off value for identification of
primary hyperaldosteronism (especially in patients without
hypokalaemia). The aim of this study was to evaluate
prevalence and characteristic of adrenal glands’ abnormalities
in hypertensive patients with an elevated plasma
aldosteron to plasma renin activity ratio.
Material and methods In 1367 subsequent adult patients
with arterial hypertension plasma renin activity was estimated
twice: first in patients receiving normally salted diet
(100–120 mmol sodium per day) after 8 hours of recumbent
position (PRA1) and a second time after 3 days of
sodium restriction (10–20 mmol sodium per day) and
3 hours of upright position (PRA2). Plasma aldosterone
concentration was assessed only in patients with low PRA1
(< 1 ng/ml/h) and without or only marginal reaction of PRA
to salt restriction and upright position (PRA2/PRA1 < 1.5).
Plasma aldosteron concentration was assessed also twice
on normally salted diet and after sodium retriction
(ALDO1 and ALDO2). In patients with ALDO/PRA ≥ 50
a CT scan of adrenal glands and a saline infusion test were
performed.
Results ALDO/PRA ≥ 50 was found in 36 patients (2.6%
of the entire hypertensive group). In that subgroup frequency
of hypokaliaemia (< 3,5 mmol/l) was significantly
higher than in hypertensive patients with a lower ALDO/PRA ratio. Computed tomography was performed in
34 out of these 36 patients. The scans revealed no abnormalities
in 44.1% (n = 15). The most frequent abnormalities
were: isolated adrenal tumour and bilateral adrenal
enlargement. Saline infusion test was performed in 24 patients.
A positive result was obtained in 15 cases. The ROC
analysis revealed, that a ALDO/PRA ratio over 147 is connected with adrenal abnormalities in 66.7% of patients and
only 21.1% changes remain unrevealed.
Conclusions 1. The prevalence of primary hyperaldosteronism
in general population of hypertensive patients
estimated according to the raised plasma aldosterone to
plasma renin activity ratio (≥ 50) is 2.6%. 2. The ALDO/PRA ratio is especially useful in diagnosis of Conn syndrome
in hypertensive patients without elevated serum aldosterone
concentration. 3. The ALDO/PRA over 147 is
highly specific for patients with morfological changes observed
in computed tomography
Pentoxifylline and Methylprednisolone Additively Alleviate Kidney Failure and Prolong Survival of Rats after Renal Warm Ischemia-Reperfusion
Renal ischemia-reperfusion injury (IRI) induces local inflammation leading to kidney damage. Since pentoxifylline (PTX) and steroids have distinct immunomodulatory properties, we aimed to evaluate for the first time their combined use in IRI-induced acute kidney injury (AKI) and chronic kidney disease (CKD) in rats. In two experiments, PTX (100 mg/kg body weight subcutaneously) was administered 90 min prior to renal IRI or/and methylprednisolone (MP; 100 mg/kg body weight intramuscularly) was infused 60 min after reperfusion of a solitary kidney (AKI model: 45 min ischemia, 48 male Sprague-Dawley rats) or one kidney with excision of contralateral kidney 2 weeks later (CKD model: 90 min ischemia, 38 rats). Saline was infused in place of PTX or/and MP depending on the group. Renal function (diuresis, serum creatinine, creatinine clearance, sodium and potassium excretion, and urine protein/creatinine) was assessed at 48 h and 120 h post-IRI (AKI model) or 4, 16 and 24 weeks after IRI, along with survival analysis (CKD model). More evidently at early stages of AKI or CKD, treated animals showed higher glomerular filtration and diminished tubular loss of electrolytes, more so with PTX + MP than PTX or MP (serum creatinine (渭mol/L) at 48 h of AKI: 60.9 卤 19.1 vs. 131.1 卤 94.4 vs. 233.4 卤 137.0, respectively, vs. 451.5 卤 114.4 in controls, all p < 0.05; and at 4 weeks of CKD: 89.0 卤 31.9 vs. 118.1 卤 64.5 vs. 156.9 卤 72.6, respectively, vs. 222.9 卤 91.4 in controls, p < 0.05 for PTX or PTX + MP vs. controls and PTX + MP vs. MP). Survival was better by >2-fold with PTX + MP (89%) vs. controls (40%; p < 0.05). PTX + MP largely protect from IRI-induced AKI and CKD and subsequent mortality in rats. This calls for clinical investigations, especially in kidney transplantation