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Z Zukowska-Grójec

Publications and source records attributed to Z Zukowska-Grójec.

14 recordsLinked to original sources
PubMed1998

Alterations in plasma neuropeptide Y immunoreactivity and catecholamine levels during surgical removal of pheochromocytoma.

BACKGROUND: Neuropeptide Y, an abundant neurohormone present with catecholamines in the adrenal medulla, is a potent non-adrenergic vasoconstrictor and a vascular growth factor. OBJECTIVE: To determine the mechanism of the release from, and possible role of neuropeptide Y in, pheochromocytomas, compared with those of catecholamines. METHODS: Plasma and tumour levels of neuropeptide Y-immunoreactivity (by, radioimmunoassay) and of noradrenaline and adrenaline (by a radioenzymatic method) in 29 patients (19 women and 10 men, aged 22-68 years) were measured during surgical removal of the tumour, during alpha-adrenergic and beta-adrenergic blockade. Arterial systemic blood samples were withdrawn before the ligation of the vessels supplying the tumour, during its surgical manipulations and after its removal, while haemodynamics was monitored. RESULTS: Plasma neuropeptide Y levels in 17 patients (58.6%, group I) significantly increased during manipulations of the pheochromocytoma and returned completely to normal after its removal. This response was independent of the plasma neuropeptide Y immunoreactivity manipulation and was correlated to increases in plasma noradrenaline (r = 0.638, P < 0.02) but not adrenaline levels. Manipulation-induced increases in plasma neuropeptide Y-immunoreactivity were associated with greater neuropeptide Y content in tumours (r = 0.508, P < 0.05) but neither plasma nor tumour levels of neuropeptide Y immunoreactivity were correlated to tumour mass. Plasma levels of neuropeptide Y immunoreactivity in the remaining 12 patients (41.4%, group II) remained unchanged throughout the experimental period, while levels of circulating catecholamine rose. In all, in spite of our attempt at complete adrenergic blockade, tumour manipulation elevated arterial blood pressure and these changes were significantly correlated to increases in levels of catecholamines in patients in both groups but also to plasma neuropeptide Y immunoreactivity in patients in group I. CONCLUSION: Pheochromocytomas exhibit different patterns of secretion. For about half of the patients either the secretion of neuropeptide Y is uncoupled from that of catecholamines or its secretion could be obscured by an increase in degradation of neuropeptide Y to inactive fragments undetectable by radioimmunoassay.

Adult↗
PubMed1982

Sympathetic reactivity to upright posture in borderline and established hypertension.

Plasma and urinary catecholamines and their metabolites were estimated in 18 patients with borderline hypertension (BH), 27 patients with established hypertension (EH) and 15 healthy subjects in basal conditions and after 20-min standing. Patients with EH differed from the remaining groups, showing decreased urinary excretion of noradrenaline (NA). In patients with BH, in comparison with controls, an augmented plasma NA in basal conditions as well as a more pronounced increment of plasma NA in response to upright posture was observed. Moreover, in BH increased urinary excretion of dopamine, homovanillic acid and 3-methoxy-4-hydroxyphenylglycol has been found. In patients with BH the increase of diastolic blood pressure in response to upright posture was associated with an exaggerated increase of plasma NA and adrenaline. The results of the study show that patients with BH are characterized by sympathetic overactivity and suggest that in this type of hypertension this factor may play a role in response of blood pressure to physiological stimuli.

Adolescent↗
PubMed1979

Plasma noradrenaline response to sustained handgrip in patients with essential hypertension.

The responses of plasma noradrenaline, arterial blood pressure, and heart rate to sustained handgrip at 30% maximal voluntary contraction were studied in untreated patients with essential hypertension and in healthy subjects of comparable age. There were no significant differences between these two groups in the intensity and duration of handgrip. Increases in heart rate and blood pressure induced by the effort were similar in hypertensive patients and normotensive control subjects, whereas the absolute levels of blood pressure were considerably higher in the patients. In the first 1-2 min of exercise the increases in plasma noradrenaline concentration were similar in both groups. Subsequently, plasma noradrenaline concentration tended to plateau in hypertensive patients while in control subjects it continued to increase. The elevation of plasma noradrenaline in the last minute of effort was, therefore, significantly smaller in hypertensive patients than in the control group.

Adolescent↗
PubMedDate not supplied

Tissue catecholamine concentrations in spontaneously hypertensive rats.

Tissue concentrations of noradrenaline (NA), dopamine (DA) and adrenaline (A) were compared in spontaneously hypertensive (SHR) and normotensive (NCR) rats, aged 1, 3, 8, 14 and 24 weeks The organs analyzed included the brain, subdivided into prosencephalon and rhombencephalon, heart, adrenal glands and kidney. Brain catecholamines were significantly lower in SHR than in NCR, and the difference appeared already at the age of 3 weeks. Concomitant increase was found in the adrenal NA and A concentrations of the SHR. Concentration of NA in the heart decreased in the SHR following onset of hypertension. It is concluded that the diminished NA, DA and A concentrations in the brain as well as the augmented adrenal NA and A levels in the SHR may be causally related to the development of hypertension, while the heart NA level reflects the secondary, hypertension -- related changes.

Adrenal Glands↗
PubMedDate not supplied

Metabolism of 3H-catecholamines in the brain of spontaneously hypersensitive rats (SHR) after running stress.

The influence of stress on the metabolism of adrenaline (A) and noradrenaline (NA) in the prosencephalon (PC) and rhombencephalon (RC) of SHR and normotensive Wistar rats (WR) was studied. After intraperitoneal injection of 3H-tyrosine, radioactivity of 3H-adrenaline (3H-A), 3H-noradrenaline (3H-NA), total 3H-3-methoxy-4-hydroxyphenylglycol (3H-MHPG), total 3H-3,4-dihydroxyphenylglycol (3H-DHPG) and 3H-vanillylmandelic acid (3H-VMA) was measured in PC and RC of SHR and WR, non-stressed or subjected to running stress. Stress induced a significant decrease of 3H-A level in PC and RC of 8-week-old SHR while no stress-related changes in 3H-NA level were found in either part of the brain of SHR. In RC, 3H-A level was lower in older than in younger non-stressed SHR and decreased further after stress. In all SHR, stress enhanced formation of total 3H-MHPG and/or 3H-DHPG in PC, while increased 3H-VMA level was found only in PC of 24-week-old and in RC of 8-week-old stressed SHR. The results suggest that the decrease of the level of 3H-A in the brain of SHR is involved in their reaction to stress and may depend on increased metabolism mainly to glycols but also to VMA. The lower 3H-NA and 3H-A levels in the prosencephalon of non-stressed young and older SHR, concomitant with unaltered or elevated formation of their metabolites, may suggest higher release of the transmitters involved in the pathogenesis of spontaneous hypertension.

Animals↗
PubMedDate not supplied

Metabolism of 3H-catecholamines in the heart and adrenals of spontaneously hypertensive rats (SHR) after running stress.

The metabolism of 3H-catecholamines after i.p. injection of 3H-tyrosine was studied in the heart and adrenals of spontaneously hypertensive (SHR) and normotensive Wistar (NCR) rats at rest and following running stress. In the heart of 8-week-old NCR a sharp stress-induced increase of the levels of 3H-A and 3H-DA with an elevation of the levels of their metabolites was observed. In contrast, there was no stress-related change in the levels of 3H-NA, 3H-A and 3H-VMA in the hearts of young SHR, while the 3H-DA level, though increased after stress, remained still lower than in the age-matched NCR. In the phase of established hypertension (24 weeks) lower levels of 3H-NA and 3H-A in the heart already present at rest, as compared with NCR, remained lower after stress but the elevation of the level of their metabolites 3H-VMA and 3H-MA, was similar in both strains. In the adrenals of 8-week-old SHR the basal 3H-A level was already higher than in NCR. Stress provoked a marked decrease of adrenal 3H-A accompanied by increased formation of 3H-MA and an increase in the levels of 3H-NA and 3H-DA, more pronounced in SHR than NCR. In the phase of advanced hypertension a further elevation of 3H-A and 3H-MA and an increase of basal 3H-DA level in the adrenals were found at rest. The decreased levels of 3H-catecholamines in the heart of stressed young and non-stressed older SHR may indicate an increase in their rate of release and/or their impaired synthesis. An increased basal level of 3H-A in the adrenals of SHR concomitant with the development of hypertension, may reflect an increased synthesis and/or decreased release, as evidenced by the proportionally lower increase of its extraneuronal metabolite 3H-MA. The adrenal response to stress, more intense in SHR than in NCR, may be considered as due to enhanced release of 3H-A from the gland.

Adrenal Glands↗
PubMedDate not supplied

Neuropeptide Y and alpha-adrenoceptor interactions in patients with essential hypertension.

Neuropeptide Y (NPY) is a vasoconstrictor sympathetic cotransmitter and a modulator of adrenergic function whose role in hypertension is yet unknown. We studied the co-release of NPY and noradrenaline (NA) in patients with essential hypertension (13 females, 11 males, age 42 +/- 13 years) by measuring plasma levels of NPY-immunoreactivity (-ir, radioimmunoassay) and NA (radioenzymatic method) following administration of clonidine (CL 300 micrograms, p.o.). At rest, only NPY-ir levels significantly correlated with diastolic blood pressure (DBP, r = 0.42, p < 0.05). Three hours after CL, there were a decrease in mean arterial pressure and plasma NA (by 31 +/- 14 mmHG, p < 0.05 and 92 +/- 10 pg/ml, p < 0.01) but no change in NPY-ir levels. Patients were subsequently subdivided into groups with high (> or = 90 mmHg) or normal DBP (< or = 89 mmHg) and with or without elevated plasma NA levels (above or below 414 pg/ml, a normotensive mean +1 standard deviation). In hypertensives, but not in those with normal DBP, plasma NPY-ir correlated not only with DBP but also with systolic and mean blood pressure (r = 0.53 and r = 0.60, respectively) at rest. Hypertensives with "high" NA had significantly lower resting plasma NPY-ir levels than those with "low" NA (7.1 +/- 3.6 vs 14.7 +/- 6.0 fmol/ml, p < 0.05). In the former group, CL evoked the greatest fall in plasma NA, and also decreased NPY-ir levels by 50% (p < 0.05). Thus, patients with essential hypertension were found to display differential patterns of changes in sympathetic cotransmitters to clonidine. NPY may contribute to the increased blood pressure in hypertensives and together with NA, mediate hypotensive action of clonidine but only in the hyperadrenergic subgroup of hypertensives.

Adult↗