Na+ and Mg2+ contents in smooth muscle cells in spontaneously hypertensive rats.

Whereas in blood cells decreased magnesium concentrations and increased sodium concentrations in essential hypertension have often been described, only sparse data exist on cellular magnesium or sodium content and exchange in vascular smooth muscle cells. Therefore in aortic smooth muscle cells from 10 spontaneously hypertensive rats (SHR) of the Münster strain and 10 normotensive Wistar-Kyoto rats (WKY) aged 8 to 10 months, the intracellular magnesium and sodium content was measured. Electron-probe X-ray microanalysis was used to determine intracellular Mg2+ and Na+ concentrations in aortic cryosections 3 microm thick. The magnesium ion content was 0.90 +/- 0.15 g/kg dry weight in SHR versus 1.15 +/- 0.10 g/kg dry weight in WKY (means +/- SD, P < .05). Vascular smooth muscle sodium ion content was 6.66 +/- 0.39 g/kg dry weight in WKY and 12.61 +/- 0.91 g/kg dry weight in SHR (P < .01). Aortic smooth muscle cells from SHR are characterized by markedly lowered intracellular magnesium ion content and increased sodium ion concentrations in animals 8 to 10 months old, compared with normotensive cells. The results may be due to genetically determined disturbances in transmembrane magnesium and sodium ion transport.

Studies on diurnal blood pressure variation in kidney diseases associated with excessive salt and water retention.

Salt and water retention, a cardinal feature of nephrotic syndrome, was suggested to be an important factor leading to reduced diurnal blood pressure (BP) variation in renoparenchymal disease. Twenty-four hour BP (SpaceLabs SL 90207), 24-h urine excretion of catecholamines, plasma renin activity and plasma aldosterone concentration were therefore determined in 10 nephrotic patients with normal serum creatinine levels (group A, serum creatinine 1.0+/-0.2 mg/dl), in 10 nephrotic patients with increased serum creatinine levels (group B, serum creatinine 2.4+/-0.9 mg/dl) and in 20 controls matched in respect of age and BP. To study the direct influence of fluid volume overload, diurnal BP variation was determined before and after volume depletion by ultrafiltration in 10 patients with end-stage renal failure. Diurnal BP variation was characterised by the difference of mean BP during daytime (10 pm to 8 am) and night-time (8 am to 10 pm). In group A, the systolic and diastolic day-night difference was not changed when compared with the controls (NS). In contrast, in group B the day-night difference was significantly lower than in the controls (P < 0.01). Twenty-four hour urine catecholamine excretion and plasma aldosterone were comparable between the study groups. Plasma renin activity, however, was significantly increased in group A (P < 0.05). Nocturnal BP drop was not related to plasma renin activity in the nephrotic patients. The blunted diurnal blood pressure variation in end-stage renal failure was not influenced by ultrafiltration. The study demonstrates that the blunted diurnal BP variation in kidney disease is unaffected by marked changes in total exchangeable sodium and fluid volume, but is sensitive to changes in glomerular filtration rate.

A randomized multicenter trial of the anti-ICAM-1 monoclonal antibody (enlimomab) for the prevention of acute rejection and delayed onset of graft function in cadaveric renal transplantation: a report of the European Anti-ICAM-1 Renal Transplant Study Group.

BACKGROUND: T-cell activation through T-cell receptor engagement requires co-stimulatory molecules and also adhesion molecules such as ICAM-1. Moreover ICAM-1 mediates leukocyte invasion from the blood into tissue during inflammatory processes. In animal studies using mouse monoclonal antibodies against ICAM-1 (enlimomab), renal allograft survival has been improved and reperfusion damage from ischemia reduced. The European Anti-ICAM-1 Renal Transplant Study (EARTS) was a randomized, double-blind, parallel-group, placebo-controlled study lastingl year and performed in 10 transplant centers in Europe. METHODS: A total of 262 recipients of cadaveric kidneys were given either enlimomab or a placebo for 6 days and were given triple immunosuppressive therapy of cyclosporine, azathioprine, and prednisolone. The primary efficacy endpoint was the incidence of the first acute rejection within 3 months, and each event was assessed by a committee including investigators and independent pathologists. RESULTS: There was no significant difference in the incidences of first acute rejection at 3 months between the placebo and enlimomab groups (39% vs. 45%), and enlimomab did not reduce the risk of delayed onset of graft function (DGF) (26% vs. 31%). Neither was there a difference in patient survival (95% vs. 91%) or graft survival (89% vs. 84%) at 1 year. Fatal events occurred in 19 (7%) patients (7 placebo, 12 enlimomab). Clinically, the most important non-fatal adverse events were infections; however, there was no statistically significant difference between the incidences in the two groups (70% vs. 79%). CONCLUSION: Short term enlimomab induction therapy after renal transplantation did not reduce the rate of acute rejection or DGF.

Electron-probe X-ray Microanalysis of Magnesium and Sodium Ion Content in Vascular Smooth Muscle Cells from Spontaneously Hypertensive and Normotensive Rats.

Whereas in blood cells decreased magnesium concentrations and increased sodium concentrations in essential hypertension have often been described, only sparse data exist on cellular magnesium or sodium content in vascular smooth muscle cells. Therefore, in aortic smooth muscle cells from seven spontaneously hypertensive rats (SHR) of the Münster strain and seven normotensive Wistar-Kyoto rats (WKY), the intracellular magnesium and sodium content were measured by electron-probe X-ray microanalysis. Measurements were performed in aortic cryosections 3 µm thick. The magnesium ion content was 0.93 +/- 0.17 g/kg dry weight in SHR vs 1.14 +/- 0.12 g/kg dry weight in WKY (p < 0.05). Vascular smooth muscle sodium ion content was measured at 6.85 +/- 0.59 g/kg dry weight in WKY and 12.47 +/- 1.62 g/kg dry weight in SHR (p < 0.05). In conclusion, aortic smooth muscle cells from SHR are characterized by a markedly lowered intracellular magnesium ion content and increased sodium ion concentrations compared with normotensive cells. The results may be due to genetically determined disturbances in transmembrane magnesium and sodium ion transport. Cellular magnesium and sodium handling may be disturbed in SHR aortic smooth muscle as it is in hypertensive blood cells.

Decreased membrane Mg2+ concentrations in a subgroup of hypertensives: membrane model for the pathogenesis of primary hypertension.

Intracellular Mg2+ measurements were performed in erythrocyte membranes of 18 untreated normotensive and 19 untreated essential hypertensive patients. Mg2+ concentrations were determined by atomic absorption spectroscopy using a Video 12 apparatus. The results show that in patients with essential hypertension total Mg2+ content in erythrocyte membranes was significantly decreased as compared with the control group (0.28 +/-0.05 v 0.52+/-0.15 mmol/g membrane protein; mean+/-SD, P < .001). Additionally, plasma and free intracellular Mg2+ content of lymphocytes and platelets showed no significant difference in normotensives and hypertensives. Lowered total membrane Mg2+ concentrations in a subgroup of primary hypertensives may contribute to the development of this disorder, perhaps due to different buffering or membrane transport systems.

Increased Na+ and decreased Mg2+ intracellular concentrations in vascular smooth muscle cells from spontaneously hypertensive rats.

1. Although in blood cells decreased magnesium concentrations and increased sodium concentrations in essential hypertension have often been described, only sparse data exist on cellular magnesium or sodium content and exchange in vascular smooth muscle cells.2. Therefore in aortic smooth muscle cells from 10 spontaneously hypertensive rats (SHR) of the Münster strain and 10 normotensive Wistar-Kyoto rats (WKY) aged 3 and 8-10 months, the intracellular magnesium and sodium content was measured.3.Electron-probe X-ray microanalysis was used to determine intracellular Mg2+ and Na+ concentrations in aortic cryosections 3 micron thick. The Mg2+ content was 47+/-13 mmol/kg dry weight in SHR versus 48+/-19 mmol/kg dry weight in WKY aged 3 months, and 37+/-6 mmol/kg dry weight in SHR versus 47+/-4 mmol/kg dry weight in WKY aged 8-10 months (P<0. 05). Vascular smooth muscle Na+ content was 283+/-59 mmol/kg dry weight in WKY and 402+/-123 mmol/kg dry weight in SHR aged 3 months (P<0.05), and 289+/-17 mmol/kg dry weight in WKY versus 548+/-39 mmol/kg dry weight in SHR aged 8-10 months (P<0.05).4. Aortic smooth muscle cells from SHR are characterized by a markedly lower intracellular Mg2+ content in 8-10-month-old animals and increased Na+ concentrations compared with normotensive cells in 3- and 8-10-month-old rats. The results may be due to genetically determined disturbances in transmembrane Mg2+ and Na+ transport. Cellular magnesium and sodium handling may be disturbed in SHR aortic smooth muscle as it is in hypertensive blood cells. In addition, it is concluded that vascular smooth muscle cell Mg2+-Na+ exchanger can be altered in a subgroup of SHR.

Efficacy and tolerability of once-daily barnidipine in the clinical management of patients with mild to moderate essential hypertension.

Four multicentre trials have investigated the efficacy and tolerability of treatment with once-daily, modified-release capsules of barnidipine, a long-acting dihydropyridine calcium antagonist, in patients with mild to moderate essential hypertension. In two of these trials, the clinical profile of barnidipine was compared with those of amlodipine and nitrendipine, which belong to the same class of drug as barnidipine, in a randomized, double-blind, parallel-group manner. In one study, 37 patients received amlodipine and 79 patients received barnidipine. In a second study, 46 patients received nitrendipine and 96 received barnidipine. In each trial, a 4-week placebo run-in phase was followed by a 12-week comparative phase. Changes in sitting and standing diastolic and systolic blood pressures were assessed, and adverse events were recorded. Both studies demonstrated that the antihypertensive efficacy of barnidipine was equivalent to each comparator agent, but barnidipine tended to produce fewer class I adverse reactions. The long-term efficacy and safety of barnidipine were demonstrated in an open-label study. In total, 106 patients were followed for the first year of the study, during which time they received barnidipine at a dose titrated to achieve a sitting diastolic blood pressure of less than 90 mm Hg; if necessary, another antihypertensive agent was added to achieve normalization of blood pressure. Seventy-nine of these patients, most of whom were maintained on barnidipine monotherapy, were followed for a second year, and 32 patients, all of whom received barnidipine monotherapy throughout the study period, were followed for a third year. Blood pressure normalization after 1 year of follow-up was achieved in 91% of patients, and was maintained for the second and third years in 91% and 81% of patients, respectively. The incidence of adverse events, possibly or probably attributable to barnidipine, was 22%, 14% and 3%, respectively, during each successive year. The suitability of barnidipine for once-daily dosing was confirmed in a randomized, double-blind, placebo-controlled, crossover study of 20 patients. These patients were given 6-week regimens of both barnidipine (20 mg) and placebo, preceding 24-h ambulatory blood pressure monitoring. Barnidipine lowered blood pressure to a significantly greater extent than placebo both at night and during the day. These studies suggest that barnidipine possesses equivalent efficacy to amlodipine and nitrendipine, but produces fewer class-specific side-effects. It provides 24-h efficacy from a once-daily dosing regimen, and this efficacy and its safety profile are maintained for at least 3 years.

Effect of diadenosine polyphosphates on Ca2+ ATPase activity.

Diadenosine tri-, tetra-, penta-, and hexaphosphate (Ap3A, Ap4A, Ap5A and Ap6A) have been described as having various effects on vascular tone depending on the number of phosphate groups. This study examined the effect of diadenosine polyphosphates on Ca2+ ATPase activity. The activity of the enzyme was measured spectrophotometrically as the difference in hydrolysis of ATP in the presence and absence of Ca2+ with various concentrations of ATP and diadenosine polyphosphates. The diadenosine polyphosphates increased the activity of the Ca2+ ATPase. The effect tended to be stronger with Ap5A and Ap6A than with Ap3A and Ap4A in the order of potency: Ap3A approximately AP4A < Ap5A approximately AP6A. The stimulatory effect of diadenosine polyphosphates was not competitive with that of ATP, suggesting an allosteric activation of Ca2+ ATPase by diadenosine polyphosphates. This effect may be physiologically relevant for limiting the increase in cytosolic free Ca2+ concentration elicited by diadenosine polyphosphates by receptor activation and modulating Ca2+ ATPase function under resting conditions.

Effects of cyclosporin A and FK 506 on lipid metabolism and fibrinogen in kidney transplant recipients.

After allogenic transplantations a dramatic increase in the development of arteriosclerotic plaques can be observed, which might be due to metabolic alterations, influenced by changes of the transplant organ or immunosuppression. In this study the effects of FK 506 in kidney transplant patients on cardiovascular risk factors were compared to cyclosporin A (CsA) immunosuppression. Both groups showed no statistical differences in number, kidney function, age, body weight, sex distribution, steroid dosage and follow-up time after transplantation. Total cholesterol was similar in FK 506-treated patients (231 +/- 22 vs. 278 +/- 52 mg/dl) as compared with patients with CsA immunosuppression. Furthermore, there were no differences in triglycerides (220 +/- 72 vs. 210 +/- 67 mg/dl), HDL-cholesterol (67 +/- 14 vs. 52 +/- 18 mg/dl) and fasting glucose (112 +/- 36 vs. 116 +/- 17 mg/dl). However, the concentration of LDL-cholesterol (114 +/- 21 vs. 167 +/- 37 mg/dl), the independent risk factor Lp(a) (11 +/- 9 vs. 27 +/- 8 mg/dl) and fibrinogen (216 +/- 71 vs. 297 +/- 47) was lower in FK 506-treated patients. Our results indicate that FK 506 immunosuppression offers some advantages in cardiovascular risk factors.

Decreased cellular Mg2+ concentrations in a subgroup of hypertensives--cell models for the pathogenesis of primary hypertension.

A new method to determine total Mg2+ content in lymphocytes was developed, offering advantages for routine measurements as compared to fluorescence methods. Intracellular Mg2+ measurements were performed in lymphocytes of 18 untreated normotensive and 19 untreated essential hypertensive patients. Mg2+ content was referred to lymphocytic protein, which was determined according to Bradford's method. Mg2+ measurements were performed by atomic absorption spectroscopy using a Video 12 apparatus from Thermo Electron Instrumentation Laboratory, Andover, MA, USA. The results show that in patients with essential hypertension, total intralymphocytic Mg2+ content is significantly lower (0.07 +/- 0.05 mmol/g lymphocytic protein, mean +/- s.d.) as compared to controls (0.11 +/- 0.04 mmol/g lymphocytic protein, mean +/- s.d., P < 0.05). Free intracellular Mg2+ content was measured in lymphocytes by the fluorescent indicator mag-fura-II, showing no significant difference in normotensives and hypertensives (0.30 +/- 0.16 vs 0.38 +/- 0.17 mmol/l). In platelets free intracellular Mg2+ concentrations were not found of significant difference in normotensive and hypertensive patients (0.52 +/- 0.23 vs 0.47 +/- 0.27 mmol/l) using mag-fura-II. In plasma Mg2+ concentrations there was no significant difference in the normotensive and hypertensive group (0.92 +/- 0.07 vs 0.88 to 0.07 mmol/l). There was no correlation between plasma, free or total cellular magnesium concentrations in each group. Furthermore this method also seems suitable for routine measurements of total intracellular Mg2+ concentrations in even larger groups of patients in comparison with fluorescent indicator measurements like mag-fura-II. Lowered total intracellular Mg2+ concentrations in a subgroup of primary hypertension may contribute to the development of this disorder, perhaps due to different buffering systems.

Influence of proteinuria on long-term transplant survival in kidney transplant recipients.

Long-term prognosis in kidney transplant recipients depends on multiple factors. To investigate whether mild proteinuria within the first 6 months following transplantation is a determinant of the long-term function and survival of kidney transplants, 357 patients transplanted between 1980 and 1990 were retrospectively examined over a period of 5 years. 25.5% of the patients developed an early proteinuria between 0.25 and 1.0 g/day over 6 or more months. This group was well matched concerning gender, age of recipient, underlying disease, time on hemodialysis, donor age, cold ischemia time and HLA mismatches with the group without proteinuria (n = 266). Five-year transplant survival in the group with proteinuria was 58.9% in contrast to 85.6% in recipients without proteinuria. Intermittent proteinuria did not worsen long-term prognosis. Proteinuria of 12 months or longer further reduced 5-year transplant survival to 42.6%. Over the whole observation period, serum creatinine in recipients with proteinuria was about 0.5 mg/dl higher as compared with patients without proteinuria. No correlation between proteinuria and gender, age of recipient, duration of hemodialysis, age of donor, cold ischemia time and mismatches could be detected. In conclusion, early proteinuria apparently is not due to established donor or recipient factors. However, there is a strong correlation of proteinuria with worse transplant function and survival.

Na+/H+ exchange during an oral glucose challenge in patients with essential hypertension.

To determine the effects of an oral glucose challenge on cellular Na+/H+ exchange in vivo we measured plasma glucose concentrations, plasma insulin concentrations, plasma C-peptide concentrations, arterial blood pressure, cytosolic pH (pHi) and cellular Na+/H+ exchange in 24 patients with essential hypertension (HT) and 41 age-matched healthy normotensive control subjects (NT) during a standardized oral glucose tolerance test. Under resting conditions, the plasma glucose concentrations, plasma insulin concentrations, plasma C-peptide concentrations and Na+/H+ exchange activity were significantly higher in HT compared with NT (P < 0.05 in each case). A significant increase in lymphocytic Na+/H+ exchange activity was only seen in NT (resting 0 h: (4.23 +/- 0.2) x 10(-3) pHi/s; mean +/- S.E.M.; 1 h after glucose administration: (6.00 +/- 0.56) x 10(-3) pHi/s; 2 h after glucose administration: (6.65 +/- 0.64) x 10(-3) pHi/s; P = 0.0003 by Friedman's two-way ANOVA), but not in HT (resting 0 h: (6.07 +/- 0.36) x 10(-3) pHi/s; 1 h after glucose administration: (6.72 +/- 1.02) x 10(-3) pHi/s; 2 h after glucose administration: (6.71 +/- 0.62) x 10(-3) pHi/s; P = 0.7470). During an oral glucose challenge the systolic (P < 0.0001) and diastolic (P < 0.0001) blood pressure significantly decreased in HT but not in NT. Essential hypertension shows abnormal in vivo regulation of Na+/H+ exchange and blood pressure following oral glucose intake.

[Modern antihypertensive drug therapy]. / Moderne antihypertensive Pharmakotherapie.

The role of hypertension as a major risk factor for cardio- and cerebrovascular events is well known. Various studies have shown that rigorous antihypertensive treatment can clearly reduce both cerebrovascular and cardiovascular mortality. In recent years, the therapeutic aims of antihypertensive treatment have undergone considerable changes, and to the pre-eminent aim of blood pressure reduction has been added organ protection, which is now a major effect of modern antihypertensive therapy. Today, the selection of an antihypertensive agent is decided not solely on the basis of blood pressure, but to a large extent by the requirements of organ protection and the specifics of the underlying disease. To enable individually effective antihypertensive treatment, a knowledge of the pharmacological profile of the various drugs available, and of the respective broad spectrum of side effects is an important precondition. Although non-drug therapeutic measures also have a part to play in the treatment of hypertension, antihypertensive drugs remain the most important tool for treating essential arterial hypertension.

[Polyneuropathy, diarrhea]. / Polyneuropathie, Diarrhöe.

A 44-year-old patient with 24 kg reduction of body weight within three years due to recurrent diarrhea was admitted to the hospital. Physical findings of the patient were not remarkable, except for hypesthesia and hypalgesia of the front of the tibia and of the lower legs. Laboratory as well as endoscopic and functional examinations of the gastrointestinal tract did not reveal any remarkable finding. Infectious origins of the disease were excluded. A histological examination of a rectum specimen yielded amyloid deposits in the submucosa of the rectum. In the family history of the patient, relatives with liver and gastrointestinal diseases due to amyloidosis were detected. Amyloid deposits and the positive family history of the patient led to the diagnosis of a gastrointestinal manifestation of familial amyloidosis.

[Acute tetraplegia, diabetes mellitus (clin conference)]. / Akute Tetraparese, Diabetes mellitus.

A 48-year-old patient with massive obesity developed a dramatic increase of serum glucose and sodium concentration as first symptom of a so far unknown diabetes mellitus. A treatment with intravenous insulin infusion and administration of free water was initiated. Two weeks after this event he became comatose, developed dysphagia, a speech disorder and ocular bobbing; finally, he showed the picture of a complete tetraparesis. Computertomographic findings of the brain were unremarkable. Two weeks later physical findings of the patient showed a significant improvement. Dysphagia, speech disorder and even the tetraparesis disappeared. Computertomography of the brain now yielded a hypodense area within the pons. The symptoms can be understood as signs of central pontine myelinolysis, which may be due to hypo-osmolarity or fast equilibration of a hypo-osmolarity. The history of this patient is a rare example of a central pontine myelinolysis with spontaneous remission.

Reduced distensibility of the common carotid artery in patients treated with ergotamine.

To investigate the effect of vascular smooth muscle contraction on mechanical vessel wall properties of proximal "elastic" arteries, we investigated the effect of the vasoconstrictor ergotamine on the distensibility of the common carotid artery in 10 migraine patients with ergotamine intake, in 10 control patients with migraine headache but no prior ergotamine intake, and in 10 healthy control subjects. The patients and control subjects were matched for age, blood pressure, and sex. In the ergotamine group, 2.2 +/- 1.4 mg ergotamine tartrate (0.25 to 6 mg) was taken within 12 hours before investigation. Differences in mean 24-hour blood pressure between the study groups were excluded by 24-hour blood pressure recording and differences in arterial wall thickness by high-resolution and differences in arterial wall thickness by high-resolution B-mode ultrasound. A multigate Doppler system was used for measurement of vessel wall movements by M-mode Doppler analysis. Blood pressure was determined by sphygmomanometry. The end-diastolic diameter of the common carotid artery was insignificantly reduced in the ergotamine group compared with the healthy control subjects and control patients (healthy control subjects, 6.6 +/- 0.4 mm; control patients, 6.7 +/- 0.5 mm; patients with ergotamine intake, 6.3 +/- 0.4 mm; P = NS). Arterial distensibility was significantly lower in the patients with ergotamine intake (17.4 +/- 4.0 10(-3)/kPa) than in the healthy control subjects (22.3 +/- 5.1 10(-3)/kPa) and control patients (22.8 +/- 3.6 10(-3)/kPa) (one-way ANOVA, P = .014). The results show that ergotamine reduces the distensibility of the common carotid artery. The data suggest that vascular smooth muscle contraction can modulate the buffering function of the arterial system independently of blood pressure changes.

[Differential diagnosis and therapy of essential hypertension]. / Differentialdiagnose und Therapie der essentiellen Hypertonie.

If arterial hypertension is diagnosed in a patient, it is followed by several consequences. A life-long medical control is necessary. The history, physical examination, and biochemical diagnostics are of great importance. The secondary types of hypertension are specified and the drug therapy is suggested. A special quality in the treatment of arterial hypertension is the treatment during pregnancy.

Influence of cyclosporine A and FK506 on 24 h blood pressure monitoring in kidney transplant recipients.

Cyclosporine A (CsA) seems to exert direct effects on blood pressure and diurnal blood pressure alterations. After kidney transplant about 60% of the recipients are suffering from such alterations. In the present study, blood pressure profiles of 15 FK506-treated kidney transplant patients were compared to recipients with CsA immunosuppression. Both groups showed no statistical differences in number, kidney function, age, body weight, sex distribution and time after transplantation. Mean arterial blood pressure in FK506-treated patients at daytime was 105 +/- 2.5 mmHg, at night 109 +/- 3.0 mmHg. Systolic blood pressure difference was 2.3 mmHg, diastolic day/night blood pressure difference 0.6 mmHg, and the difference of the heart frequency 6.8 beats/min. Cyclosporin A-treated patients showed a mean arterial blood pressure during the day of 107 + 2.6 mmHg, at night-time a mean arterial blood pressure of 107 + 3.4 mmHg was measured. The diurnal blood pressure alterations of systolic blood pressure were 0.9 mmHg, diastolic blood pressure difference 3.5 mmHg respectively, the heart frequency showed a difference of 4.4 beats/min. Both, FK506-treated patients and patients with CsA immunosuppression exhibit reduced diurnal blood pressure alterations. Furthermore, mean arterial pressure in both, FK506 and CsA-treated patients was elevated and showed no statistical differences between the groups. In FK506-treated patients, however, antihypertensive therapy was less intensive. Concerning arterial blood pressure and diurnal blood pressure alterations, FK506 offers no advantages as compared to cyclosporine A. The reduced usage of antihypertensive drugs, however, may give evidence for lower hypertensive properties of FK506 as compared to CsA.

Different effects of hypertension, atherosclerosis and hyperlipidaemia on arterial distensibility.

OBJECTIVE: To investigate the different effects of hypertension, hyperlipidaemia and atherosclerosis on the visco-elastic properties of large arteries. DESIGN: Vessel wall properties were determined in patients who had been subjected for the first time to coronary arteriography. Normotensive patients with no coronary disease (n = 15), one-vessel disease (n = 15) or two- or three-vessel disease (n = 15), 15 treated hypertensive patients (mean +/- SEM duration of hypertension 9.6 +/- 1.7 years) with no coronary disease and normocholesterolaemia and 15 healthy controls were matched for blood pressure, age and sex. METHODS: Arterial distension of the common carotid artery was determined by using a multigate Doppler system. The blood pressure curve was recorded by finger plethysmography. RESULTS: The end-diastolic diameter was significantly higher in the hypertensives (P<0.05) but not significantly different in the normotensives compared with the controls. Arterial distensibility was significantly lower in the hypertensive group [(13.3 +/- 0.8) x 10(-3)/kPa] than in the controls [(19.1 +/- 1.5) x 10(-3)/kP; P<0.01), in the group with no coronary disease [(18.8 +/- 1.3) x 10(-3)/kPa; P<0.01] and in those with one-vessel disease [(17.7 +/- 1.4) x 10(-3)/kPa; P<0.05]. Arterial distensibility was not significantly lower in the hypertensives than in the group with two- or three-vessel disease [(15.0 +/- 1.0) x 10(-3)/kPa; NS). No significant correlation was found between cholesterol or lipoprotein(a) levels and arterial distensibility in the normotensive patients. CONCLUSIONS: Hypertension is the predominant factor affecting the visco-elastic properties of large arteries. Arterial compliance is significantly altered only in extensive atherosclerosis.

Lymphocytic Na(+)-H+ exchange increases after an oral glucose challenge.

The effects of oral glucose challenge on plasma glucose concentration, plasma insulin concentration, arterial blood pressure, cytosolic pH (pHi), cytosolic free Na+ concentration ([Na+]i), and cellular Na(+)-H+ exchange activity were investigated in 16 healthy subjects. The pHi, [Na+]i, and Na(+)-H+ exchange activity were measured in intact lymphocytes by using the fluorescent dye technique. The oral glucose challenge significantly increased plasma glucose, plasma insulin, and the lymphocytic Na(+)-H+ exchange activity, measured as change of pHi per second (control [0 hours], 5.20 +/- 0.53 x 10(-3) dpHi/s; 1 hour after glucose administration, 8.28 +/- 1.07 x 10(-3) dpHi/s; 2 hours after glucose administration, 8.15 +/- 1.18 x 10(-3) dpHi/s; P = .002). The lymphocytic Na(+)-H+ exchange was significantly correlated with plasma glucose concentration (r = .357, P = .041). During steady state euglycemic hyperinsulinemic clamp, the Na(+)-H+ exchange activity was not significantly changed compared with baseline values. The study shows that changes of blood glucose levels can induce an acute increase in Na(+)-H+ exchange activity. Systolic blood pressure and Na(+)-H+ exchange activity were significantly (P < .001) but weakly correlated during an oral glucose challenge.