摘要:

This bibliography is produced in association withCurrent Opinion in Cardiology(Gower Academic Journals Ltd, UK) and is compiled from over 150 journals (these are listed at the end of the bibliography in this issue). Each issue of theJournal of Hypertensionwill list papers relevant to hypertension, published over a two-month period. A cumulative bibliography, covering 12 months and arranged under subject headings, will appear in the first issue (February) each year. A complete, updated list of the journals scanned will be published at the same time as the cumulative bibliography.

ISSN:0263-6352    

出版商:OVID    

年代:1987

数据来源: OVID

ISSN:0263-6352    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

Previous investigations have reported the systemic haemodynamic characteristics of obese hypertensive patients; however, their renal haemodynamics have not been explored. This report compares the renal and systemic haemodynamic findings in obese and lean normotensive and hypertensive patients. Our results demonstrate that both normotensive and hypertensive obese subjects had an increased renal blood flow, total blood volume and cardiac output, with decreased total peripheral and renal vascular resistances in comparison with lean normotensive and hypertensive patients. Body weight correlated directly and significantly with total blood volume, cardiac output and renal blood flow but indirectly with total peripheral resistance. Therefore, the elevated cardiac output and volume expansion found in obese patients were associated with increased renal perfusion; this increased renal blood flow accounts for the reduced renal vascular resistance in patients with obesity hypertension. Thus, we suggest that this effect of volume expansion in obesity could counteract the opposing effect of active vasoconstriction produced by the hypertensive disease and may account for the difference in prognosis of obese and lean hypertensive patients.

ISSN:0263-6352    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

Basal platelet function was measured in 35 40-year-old men with untreated mild essential hypertension and compared with 44 age-matched normotensive men. The groups differed significantly with respect to platelet size in venous blood (hypertensive, 7.46 ± 0.10 x 10-15I versus normotensive, 7.11 ± 0.09 x 10-15I;P= 0.01) and arterial concentration of the platelet-specific protein β-thromboglobulin (hypertensive, 1.11 ± 0.23 nmol/l versus normotensive, 0.59 ± 0.04 nmol/l;P= 0.02). The normotensive subjects had significantly higher β-thromboglobulin (BTG) in venous than in arterial blood (P< 0.01). The hypertensive men showed no such difference. In contrast to the normotensive subjects, the hypertensive group had reduced arterial compared with venous platelet count (P< 0.01). This may reflect an increased liability in the hypertensive subjects to lose platelets through adherence to the cannula during arterial blood sampling. The above findings point to increased platelet activity in essential hypertension, particularly in arterial blood.

ISSN:0263-6352    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

Instrumented normotensive and two-kidney, one clip Goldblatt hypertensive dogs were placed on normal salt, high salt and DOCA-salt regimens and the effect on mean arterial blood pressure (MAP) and iliac vascular resistance (IVR) determined. High salt and DOCA-salt did not alter these variables in the Goldblatt hypertensive group. DOCA-salt increased MAP in the normotensives by 12 mmHg; however, IVR was not significantly increased by this treatment. In order to determine the degree of sympathetic tone in the iliac vascular bed, the change in IVR evoked by the α1-adrenoceptor antagonists, urapidil and prazosin, was assessed. There were similar reductions in MAP and IVR after α1-blockade in both groups of dogs, regardless of the salt regimen. However, urapidil caused a greater decrease in MAP in the normotensives than in the hypertensives. Captopril administration after α1-blockade caused further reductions in MAP and IVR in the hypertensives, and in the MAP of the normotensive dogs on normal or high salt, indicating that the renin-angiotensin system maintained blood pressure in these groups. These results suggest that sympathetic tone is not increased by high salt- or DOCA-salt in normotensive or Goldblatt hypertensive dogs for the 8–11 day duration of these treatments.

ISSN:0263-6352    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

An examination has been made of the blood pressure (BP), saline preference and circulating renin-angiotensin system of spontaneously hypertensive rats (SHR) of the Okamoto strain, normotensive Sprague-Dawley (SD) rats, SHR suckled from immediately after birth on an SD foster mother (SHR-on-SD) and SD cross-suckled on an SHR foster mother (SD-on-SHR). While the BP of SD-on-SHR was not significantly different from that of control SD, SHR-on-SD had significantly lower BP than SHR suckled on their natural mothers. In two-bottle preference tests, neither the saline preference nor total fluid intake of cross-suckled SHR was significantly different from that of SHR controls. While the total fluid intake of SD-on-SHR was not different from that of SD controls, the saline preference of cross-suckled SD was significantly lower than that of control SD. The heart, adrenal and kidney weights of SHR were significantly greater than those of SD, but there were no significant differences between cross-suckled rats and their respective controls.There were no significant differences in plasma renin activity (PRA) or angiotensin converting enzyme (ACE) activity between any groups and these variables did not correlate with each other, with BP or with saline preference. Thus, some factor transferred from the SHR mother postnatally is required for full expression of the elevated BP, but not the exaggerated saline preference of the SHR. Conversely, the saline preference of SD, but not the BP, is altered by cross-suckling.

ISSN:0263-6352    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

We have studied the role of afferent renal nerve fibres in anaesthetized cats in mediating the decrease in sodium and water excretion from the contralateral kidney caused by unilateral renal denervation. Transient denervation of one kidney obtained by cooling of the left renal nerves increases contralateral efferent renal nerve activity and decreased sodium and water excretion from the opposite kidney. The results observed in animals with intact neural pathways were compared with those obtained after the left kidney had been selectively deafferentated by cutting the dorsal roots from T9 to L4. Bilateral section of dorsal roots did not affect the increase in sodium and water excretion from the transiently denervated left kidney, but entirely abolished the decrease in sodium and water excretion from the contralateral kidney. Neither the left nor the right dorsal root section alone, affected the response of the contralateral right kidney.Our data demonstrate that afferent renal nerve fibres project bilaterally to the spinal cord and form the afferent branch of the reno-renal reflex by which one kidney can control the function of the opposite one.

ISSN:0263-6352    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

Both Adrenocorticotrophin (ACTH) and glucocorticoids raise blood pressure in man and animals, but the relationship of this and altered renal function to other cardiovascular variables, and the differences and similarities of the effects of the two agonists have not been fully explained. The present study compares the effects of ACTH (0.5 mg i.m; every 12 h) and cortisol (50 mg orally, every 6 h) in six normal men over a period of 5 days, preceded and followed by control periods of 3 and 2 days, respectively. Plasma cortisol levels were higher during ACTH treatment than during cortisol treatment. Both treatments raised blood pressure significantly and caused a marked antinatriuresis and expansion of extracellular fluid and plasma volume. ACTH also enhanced potassium excretion but this was less obvious for cortisol. Plasma concentrations of atrial natriuretic peptide rose to more than twice the basal level with both treatments.Both treatments markedly altered renal function. They raised glomerular filtration rate (GFR), i.e. inulin clearance (141% with ACTH; 113% with cortisol) although creatinine clearance was not changed, showing this to be an unreliable index during steroid administration. Filtration fraction (FF) also increased during both treatments, and renal blood flow (RBF) fell, although this achieved statistical significance only during cortisol treatment. Effective renal plasma flow [para-amino hippurate (PAH) clearance] remained unchanged while calculated renal vascular resistance increased. Fractional sodium reabsorption also rose but achieved statistical significance only during ACTH treatment. The similarity of response to treatment suggests that cortisol is largely responsible for the effects of ACTH. The respective roles of the marked increases in sodium retention, changes in fluid volume and vascular reactivity in the increases in blood pressure remain to be defined.

ISSN:0263-6352    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

Human atrial natriuretic factor (h-ANF) or its vehicle only, were infused at rates of 0.8, 1.6 and 3.2 μg/min over three successive 30-min periods, into five patients with mild essential hypertension and seven normotensive controls. Baseline (mean ± s.e.m.) plasma ANF levels were 13 ± 2 in patients and 8 ± 1 pg/ml in controls. During the first period, plasma ANF and cyclic guanosine monophosphate (cGMP) levels increased in both groups without significant alteration of blood pressure, heart rate, diuresis, natriuresis or cGMP excretion rate. During the second period of infusion, plasma ANF levels increased up to 179 ± 39 and 177 ± 30 pg/ml in patients and controls and plasma cGMP concentrations increased x 5.0 and x 4.9, respectively; natriuresis increased x 2.4 in patients and x 3.1 in controls while urinary cGMP increased x 10.9 in patients and x 10.5 in controls. During the last period, three controls became hypotensive while blood pressure remained stable in the other controls and in the patients with essential hypertension. During this period, the increases in plasma ANF concentration, diuresis, natriuresis and urinary cGMP excretion were similar in both groups. However, the mean plasma cGMP concentration after 90 min infusion was significantly higher in hypertensive patients than in control subjects (30.7 ± 3.3 versus 15.6 ± 3.4 pmol/ml,P< 0.05). The haif-life and clearance of plasma ANF, upon discontinuation of the infusion, were similar in both groups.Our data suggest that patients with mild essential hypertension have enhanced increases in plasma cGMP but normal increases in diuresis, natriuresis and cGMP excretion following infusion of h-ANF at pharmacological rates.

ISSN:0263-6352    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

The effects of propranolol (10 mg/kg) on systolic blood pressure (SBP), resting and exercising heart rates (HR), and body weight (BW) were examined in 11-week swimtrained spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. In both species, SBP was significantly reduced by either propranolol or training, but the reduction was greater with propranolol than with training. However, when propranolol was administered to rats during training, their independent beneficial effects on SBP were annulled. HR was modified slightly by propranolol and training, but they both decreased BW. The mechanism of propranolol action on BW is not clear.Maximum oxygen uptake (Vo2Max), relative heart weight (RHW), and absolute heart weight (AHW) were measured after 11 weeks of training. In both SHR and WKY rats, Vo2Max was elevated by exercise training; moreover, Vo2Max was greatest among those receiving propranolol while training. However, the combined effects of propranolol and training produced a significant reduction of AHW in SHR. The RHW was increased by training, but it was decreased by propranolol. SHR rats were more sensitive to the effects of training and propranolol than WKY rats.In humans, several observations have been reported on the attenuation of certain exercise-induced cardiovascular and metabolic changes by beta-adrenergic blocking agents. Our results obtained with rats confirm some of those observations. It would seem that the hypertensive strain of rats could serve as a model for the study of attenuation mechanisms by beta-adrenergic blockers.

ISSN:0263-6352    

出版商:OVID    

年代:1987

数据来源: OVID