Search PubMed⌕ Search

Biomedical subjects

A Wiecek

Publications and source records attributed to A Wiecek.

At least 163 records · Page 9Linked to original sources
PubMed1990

Influence of erythropoietin treatment on plasma renin activity, aldosterone, vasopressin and atrial natriuretic peptide in haemodialyzed patients.

In 5 haemodialyzed patients the influence of 3 months' erythropoietin (EPO) treatment on plasma renin activity (PRA), aldosterone (Ald), vasopressin (AVP) and atrial natriuretic peptide (ANP) was studied. Results were compared with those obtained in 7 uraemic patients showing a similar haematocrit value as patients after EPO therapy and with those obtained in 10 healthy subjects. EPO treatment did not influence significantly blood pressure but was suppressing PRA and plasma Ald levels, and raising plasma ANP concentrations. EPO treatment was without influence on AVP plasma levels. Data obtained in this study suggest that EPO-induced endocrine alterations are not due to increased blood volume and only partially related to improvement of uraemic anaemia.

Adult↗
PubMed1990

Plasma level of atrial natriuretic peptide in renal venous blood--marker of kidney ischemia?

In 12 patients with unilateral significant renal ischemia plasma levels of atrial natriuretic peptide (ANP) were estimated in renal vein blood of the ischemic (IK) and contralateral kidney (NK) and in arterial blood under supine and upright conditions. Plasma ANP levels in renal vein blood were compared with plasma renin activity (PRA) of the same blood samples. Plasma ANP levels in renal vein blood of the contralateral kidney (87 +/- 9 pg/ml) were significantly lower than in arterial blood (131 +/- 11 pg/ml) and renal vein blood of the ischemic kidney (139 +/- 16 pg/ml). In contrast plasma ANP concentrations in renal vein blood of the ischemic kidney were slightly or markedly higher than in arterial blood. A positive correlation was found between the ratio of plasma ANP in renal vein blood of the IK to that of the NK under supine condition and the respective ratio of PRA. Data presented in this paper suggest the presence of abnormal handling of ANP by an ischemic kidney and that plasma ANP levels in renal vein blood may be a marker of renal ischemia.

Adolescent↗
PubMed1990

[Effect of water immersion on glucose, insulin and atrial natriuretic factor levels in patients with transplanted heart].

In 6 heart transplant patients [HTP] and in 10 healthy subjects the influence of water immersion [WI] on blood levels of glucose, insulin and atrial natriuretic peptide [ANP] were studied. HTP showed significantly higher baseline ANP levels and a reduced response of ANP to water immersion as compared with normals. HTP did not differ from normals by baseline plasma levels of glucose and insulin. WI induced significant decline of blood glucose and increase of insulin in both examined groups. A significant correlation was found between WI induced increase of blood insulin and ANP and between the increase of ANP and decline of blood glucose both in HTP and in healthy subjects. Data presented in this paper suggest existence of a significant relationship between ANP and insulin secretion and participation of ANP in the carbohydrate metabolism both in normals and HTP.

Adult↗
PubMed1990

Influence of erythropoietin treatment on function of the pituitary-adrenal axis and somatotropin secretion in hemodialyzed patients.

In five hemodialyzed patients the influence of erythropoietin (EPO) treatment for 3 months on function of the pituitary-adrenal feedback and STH secretion was studied. Results were compared with those obtained in 6 hemodialyzed patients (No-EPO group) showing a comparable Hb concentration and Hct value as patients in the EPO group post-treatment and in 15 healthy subjects. EPO treatment was followed by a significant (ACTH and STH) or moderate (cortisol) suppression of basal plasma levels of ACTH, STH and cortisol respectively, and by a significant reduction of the response of plasma concentrations of these hormones to insulin-induced hypoglycemia. As the response of plasma levels of ACTH, STH and cortisol respectively in patients of the EPO group post-treatment differed markedly from that of the No-EPO group with similar Hb and Hct values, it seems that the EPO-induced endocrine alterations are not, at least not exclusively, a consequence of the improvement of anemia. Results presented in this study suggest that EPO treatment influences directly or indirectly the function of endocrine organs.

Adrenocorticotropic Hormone↗
PubMed1989

Endocrine abnormalities in patients with endstage renal failure.

Data presented in this study suggest existence of hyperendorphinism in uraemic patients. This hyperendorphinism may be regarded both as a primary beneficial compensatory mechanism counteracting disturbances of the internal environment, while causing secondary harmful side effects, which contribute to the uraemic state. Erythropoietin treatment of uraemic, haemodialyzed patients is followed by marked endocrine alterations (suppression of plasma levels of STH, ACTH, prolactin, glucagon, aldosterone, cortisol and plasma renin activity, elevation of plasma insulin and atrial natriuretic levels, lack of influence on plasma PTH, CT and AVP). It remains to be clarified whether the erythropoietin induced endocrine alterations are due to correction of the existing anaemia or reflect a specific effect of this hormone.

Endocrine System Diseases↗
PubMed1989

Does the kind of immunosuppressive therapy influence plasma renin activity, aldosterone and vasopressin in patients with a kidney transplant?

In 24 patients with a functioning kidney transplant and in 33 healthy subjects plasma renin activity (PRA), plasma aldosterone and vasopressin (AVP) levels were assessed under basal conditions and after dietary sodium restriction. Twelve patients were treated with azathioprine and another 12 with cyclosporine A. From the results obtained it seems that immunosuppressive drugs used in transplanted patients ar involved in the pathogenesis of endocrine abnormalities and that the kind of immunosuppressive therapy is of minor importance in their development of maintenance. Transplanted kidneys show a preserved reaction pattern of renin secretion to sodium deprivation and upright position.

Adult↗
PubMed1989

Water immersion induced alterations of atrial natriuretic peptide in patients with non-inflammatory acute renal failure.

Water immersion induced alterations of plasma atrial natriuretic peptide (ANP), circulating plasma volume (PV), plasma sodium and potassium and mean blood pressure (MAP) were examined in 12 patients with non-inflammatory acute renal failure (ARF) and in 15 healthy subjects. In patients with ARF a significantly elevated basal ANP (139 +/- 13 pg/ml versus 75 +/- 4 pg/ml in normals) and elevated MAP (112 +/- 3.5 mmHg versus 87 +/- 2 mmHg in normals) were found. Water immersion induced a significant increase in plasma ANP in both groups, which was significantly more marked in healthy subjects (152 +/- 13 pg/ml) than in patients with ARF (86 +/- 13 pg/ml). Water immersion was accompanied by a significantly more marked reduction of MAP (23 +/- 3 mmHg) and plasma sodium (6.1 +/- 0.6 mmol/l) in patients with ARF than in normals (12.7 +/- 1.5 mmHg and 4.2 +/- 0.1 mmol/l respectively). In contrast to healthy subjects, in patients with ARF water immersion did not induce enhanced diuresis. In patients with ARF a significantly more marked increase in plasma volume was found than in normals. Data obtained in this study seem to prove preservation of the physiological regulatory mechanism of ANP secretion in ARF patients but reduction of ANP release induced by central volume expansion. The importance of elevated basal plasma values in the maintenance of ARF has not been proven.

Acute Kidney Injury↗
PubMed1989

Angiotensin formation in the isolated rat hindlimb.

Local vascular generation of angiotensin was investigated in isolated perfused rat hindquarters. Extraction and combined high-performance liquid chromatography (HPLC)/radioimmunoassay analysis of hindlimb perfusate showed a spontaneous release of angiotensin I (Ang I; 5.0 +/- 3.4 fmol/h) and angiotensin II (Ang II; 31.8 +/- 7.9 fmol/h). Angiotensin converting enzyme (ACE) inhibition with captopril abolished Ang II release while Ang I levels increased more than 10-fold. Perfusion with purified hog renin caused a dose-dependent angiotensin release and vasoconstriction. The renin inhibitor H-142 abolished all effects of renin whereas ACE inhibition prevented Ang II formation and vasoconstriction but increased Ang I levels. Metabolism and pressor effects of synthetic tetradecapeptide renin substrate (TDP), Ang I and Ang II were studied using a recirculating rat hindlimb perfusion system. TDP-dependent formation of Ang I and II, and an increase in perfusion pressure was shown; ACE inhibition reduced but did not abolish Ang II formation and vasoconstriction. Ang I was converted to Ang II by about 50% during one pass through a hindlimb. This conversion was abolished by ACE inhibition. These data add support to the presence of a functional vascular renin-angiotensin system.

Angiotensin I↗
PubMed1989

Influence of parathyroidectomy on blood pressure and vascular reactivity in spontaneously hypertensive rats.

We investigated the influence of parathyroidectomy (PTX) on blood pressure (BP) and hindlimb vascular reactivity to noradrenaline (NA) and vasopressin (AVP) in male spontaneously hypertensive (SHR) and normotensive Wistar Kyoto rats (WKR). Three groups of SHR and WKR, respectively, were investigated: Sham-operated (SO) rats on a normal calcium intake (0.95%), SO rats on moderately elevated calcium intake (1.6% calcium diet) and PTX rats on the 1.6% calcium diet. At the end of the experiment (3 months), directly or indirectly measured BP was significantly lower in the PTX-SHR group on the 1.6% calcium diet than in SO-SHR on the same diet. In WKR groups, no changes of BP were recorded. Hindlimb perfusion with oxygenated Tyrode's solution for cumulative dose response curves with NA (0.1-1000 x 10(-6) M) and AVP (0.5-500 x 10(-9) M) showed no differences between PTX and SO groups. Maximal pressures and ED50 for agents used were significantly higher in SHR than WKR groups (p less than 0.05). The results support the hypothesis that the parathyroid glands contribute to high blood pressure in SHR. However, the antihypertensive action of PTX was not mediated by a change in hindlimb vascular reactivity.

Animals↗
PubMed1989

Water immersion-induced alterations of plasma atrial natriuretic peptide level and its relationship to the renin-angiotensin-aldosterone system and vasopressin secretion in acute and chronic renal failure.

Water immersion (WI)-induced alterations of circulating plasma volume (PV), plasma renin activity (PRA), plasma levels of aldosterone (Ald), vasopressin (AVP) and atrial natriuretic peptide (ANP) were examined in 12 patients with noninflammatory acute renal failure (ARF) at the anuric/oliguric phase, in 20 hemodialyzed patients with chronic renal failure and in 15 healthy subjects. Patients with acute and chronic renal failure showed significantly elevated basal ANP concentrations (138.67 +/- 12.88 and 295.8 +/- 21.87 pg/ml, respectively) as compared with normals (74.54 +/- 4.1 pg/ml) and significantly elevated PRA (20.85 +/- 3.24 and 6.60 +/- 0.94 ng/ml/h, respectively versus 2.33 +/- 0.31 ng/ml/h), plasma levels of Ald (16.11 +/- 1.26 and 18.11 +/- 1.58 ng/dl, respectively versus 12.71 +/- 1.03 ng/dl) and AVP (6.95 +/- 0.62 and 6.08 +/- 0.54 pg/ml, respectively versus 2.68 +/- 0.48 pg/ml). After 2 hrs of WI a significant decline of PRA, Ald and AVP but an increase of ANP was noted in all examined groups. The absolute WI-induced increase in plasma ANP was significantly less marked in uremic patients than in normals. The endocrine profile of patients with ARF differed only quantitatively from that of patients with CRF both under basal and WI conditions. WI was followed by a significant increase of PV which was significantly more marked in patients with ARF (+ 16.42 +/- 1.73%) than in CRF (10.57 +/- 0.37%) and in normals (+11.3 +/- 1.6%). Only in healthy subjects a significant correlation was found between WI-induced changes of PV and ANP, PRA and Ald, and between PRA and AVP.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗
PubMed1989

Atrial natriuretic peptide secretion in heart transplant patients.

Plasma atrial natriuretic peptide (ANP), plasma renin activity (PRA), aldosterone (ALD) and vasopressin (VP) were assessed in six heart transplant patients (HTP) and ten healthy subjects under bed rest conditions and 60 and 120 minutes after head-out water immersion (WI). Bed rest had no significant influence on these parameters. WI raised plasma volume (PV) to the same extent in both groups. This increase of PV was accompanied by significant suppression of PRA, ALD and VP and an increase of plasma ANP. In HTP basal plasma ANP was significantly elevated and the ANP response to central hypervolemia reduced. Significantly elevated VP plasma levels were also found in HTP. These endocrine abnormalities in HTP seem to be caused by latent failure of the transplanted heart. No direct correlation was found between plasma ANP and PRA, ALD and VP under basal conditions and after WI in either HTP or normals.

Adult↗
PubMed1989

Renal response to central volume expansion induced by water immersion (WI) in heart transplant patients.

This work was aimed to assess the secretion of volume related hormones in heart transplant patients (HTP) and their relationship to excretory renal function studied under bed rest and water immersion conditions. Fractional sodium (FENa%) and potassium (FEK%) clearance, plasma renin activity (PRA), plasma aldosterone (Ald), vasopressin (AVP) and atrial natriuretic peptide (ANP) were estimated in six HTP with moderate renal failure (C creat = 69 +/- 6.9 ml/min) and in 10 healthy subjects (N) (C creat = 110 +/- 2.0 ml/min). All HTP were treated with cyclosporine A and azathioprine. In HTP basal AVP (6.18 +/- 0.92 pg/ml) and ANP (138.17 +/- 14.69 pg/ml) levels were significantly higher than in normals (2.07 +/- 0.11 pg/ml and 74.10 +/- 7.10 pg/ml, respectively). HTP were also characterized by increased FENa% and FEK% both under bed rest (DI) and water immersion (WI) conditions. As abnormalities of excretory renal function in HTP were not significantly related to the plasma endocrine profiles factors other than PRA, Ald, AVP and ANP seemed to be also involved in their pathogenesis.

Adult↗