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Biomedical subjects

A Salvetti

Publications and source records attributed to A Salvetti.

At least 91 records · Page 5Linked to original sources

Cyclooxygenase inhibition restores nitric oxide activity in essential hypertension.

To evaluate whether cyclooxygenase constrictor substances can impair nitric oxide-mediated vasodilation in essential hypertension, in seven normotensive subjects (43.3 +/- 4.1 years; BP, 117 +/- 6/81 +/- 2 mm Hg) and seven essential hypertensive patients (47.1 +/- 5.2 years; BP, 151 +/- 8/98 +/- 4 mm Hg) we studied forearm blood flow (strain-gauge plethysmography) modifications induced by intrabrachial acetylcholine (0.15, 0.45, 1.5, 4.5, 15 micrograms.100 mL-1.min-1) in basal conditions, during infusion of NG-monomethyl-L-arginine (L-NMMA; 100 micrograms.100 mL-1.min-1), a nitirc oxide synthase inhibitor, or indomethacin (50 micrograms.100 mL-1.min-1), a cyclooxygenase inhibitor, or simultaneous indomethacin and L-NMMA. In normotensives, vasodilation to acetylcholine was blunted by L-NMMA (maximum flow increase: 671 +/- 64% and 386 +/- 42%, respectively; P < .01), and this effect was unchanged by indomethacin. In contrast, in hypertensive patients, vasodilation to acetylcholine (maximum flow increase: 458 +/- 33%) was unchanged by L-NMMA. Indomethacin significantly (P < .01) increased the response to acetylcholine (maximum flow increase: 635 +/- 53%) and restored the inhibitory effect of L-NMMA (maximum flow increase: 445 +/- 36%; P < .01 versus indomethacin alone). In an adjunctive seven normotensives (51.4 +/- 4.2 years; BP, 114 +/- 5/79 +/- 3 mm Hg) and seven essential hypertensives (53.2 +/- 7.6 years; BP, 153 +/- 9/100 +/- 3 mm Hg) we repeated the same protocol by replacing L-NMMA with L-arginine (200 micrograms.100 mL-1.min-1), the substrate for NO synthase. In normotensives, vasodilation to acetylcholine was increased by L-arginine (maximum flow increase: 539 +/- 48% and 806 +/- 61%, respectively) and this effect was unchanged by indomethacin. In hypertensive patients, vasodilation to acetylcholine (maximum flow increase: 339 +/- 32%) was unchanged by L-arginine but was significantly (P < .01) increased by indomethacin (maximum flow increase: 592 +/- 38%). Moreover, indomethacin restored the facilitatory effect of L-arginine (maximum flow increase: 804 +/- 56%; P < .01 versus indomethacin alone). Therefore, cyclooxygenase inhibition restores nitric oxide-mediated vasodilation in essential hypertension, suggesting that cyclooxygenase-dependent substances can impair nitric oxide production.

Acetylcholine↗

Hypertension causes premature aging of endothelial function in humans.

We designed the present study to evaluate whether in normotensive subjects and hypertensive patients aging causes endothelial dysfunction by a defect in the L-arginine-nitric oxide pathway or production of cyclooxygenase-dependent vasoconstrictors. In 43 normotensive subjects and 47 essential hypertensive patients, we evaluated forearm blood flow (strain-gauge plethysmography) modifications evoked by intrabrachial acetylcholine (0.15, 0.45, 1.5, 4.5, and 15 microg/100 mL per minute), an endothelium-dependent vasodilator, in the presence of saline, L-arginine (1 micromol/100 mL per minute), or indomethacin (50 microg/100 mL per minute), a cyclooxygenase inhibitor, and by sodium nitroprusside (1, 2, and 4 microg/100 mL per minute), an endothelium-independent vasodilator. Vasodilation to acetylcholine was lower (P<.01) in essential hypertensive patients than normotensive control subjects, and in both groups, it declined with advancing age. In normotensive subjects older than 30 years, L-arginine potentiated the response to acetylcholine in parallel with increasing age, whereas indomethacin increased the vasodilation to acetylcholine only in the oldest group (>60 years). In younger hypertensive patients (<30 years), L-arginine but not indomethacin potentiated the response to acetylcholine. In adult patients (31 to 45 years), L-arginine still potentiated the vasodilation to acetylcholine, and indomethacin began to show some effect. In the oldest patients (46 to 60 and >60 years), L-arginine was no longer effective, and indomethacin exerted a potentiating action that was positively related to advancing age. In normotensive and hypertensive humans, similar mechanisms, including dysfunction of the nitric oxide pathway and production of cyclooxygenase-dependent vasoconstrictors, cause age-related impairment of endothelium-dependent vasodilation, and only their earlier appearance characterizes hypertensive disease. Thus, the endothelial dysfunction that occurs in hypertension seems to represent an accelerated form of dysfunction that occurs in aging.

Acetylcholine↗

Lacidipine restores endothelium-dependent vasodilation in essential hypertensive patients.

Essential hypertension is characterized by impaired endothelium-dependent vasodilation. The present study was designed to test whether antihypertensive treatment with the calcium antagonist lacidipine can improve endothelium-dependent vasodilation in essential hypertensive patients. In 12 normotensive subjects (mean age, 47.8+/-8.6 years; blood pressure, 118.6+/-4.2/76.7+/-3.9 mm Hg) and 19 hypertensive patients (mean age, 49.4+/-10.2 years; blood pressure; 153.5+/-13.3/101.3+/-6.4 mm Hg), we studied forearm blood flow modifications (strain-gauge plethysmography) induced by intrabrachial infusion of acetylcholine (0.15, 0.45, 1.5, 4.5, and 15 microg/100 mL per minute) and bradykinin (5, 15, and 50 ng/100 mL per minute), two endothelium-dependent vasodilators that act through different receptors and signal transduction pathways, and sodium nitroprusside (1, 2, and 4 microg/100 mL per minute), an endothelium-independent vasodilator. In essential hypertensive patients, vascular reactivity was repeated during prolonged (8 weeks of oral treatment at 6 mg/d) lacidipine administration and 2 weeks after withdrawal of chronic (32-week) treatment. Hypertensive patients showed significantly (P<.01) blunted vasodilation in response to acetylcholine (vascular resistance, 31.5+/-4.9 to 7.6+/-2.4 SU) and bradykinin (vascular resistance, 32.3+/-5.8 to 8.5+/-3.0 SU) compared with control subjects (vascular resistance: acetylcholine, 24.3+/-3.9 to 3.7+/-1.2 SU; bradykinin, 24.7+/-0.4 to 4.1+/-1.3 SU), whereas the response to sodium nitroprusside was similar. After either 8 or 32 weeks of lacidipine treatment, the vasodilation in response to acetylcholine (30.6+/-7.7 to 5.7+/-1.5 and 34.3+/-6.6 to 5.9+/-1.9 SU, respectively) and bradykinin (31.3+/-7.2 to 6.4+/-1.6 and 33.7+/-5.4 to 6.1+/-1.5 SU, respectively), but not to sodium nitroprusside, proved to be significantly (P<.05) increased compared with baseline. In essential hypertensive patients, oral treatment with lacidipine increased forearm vasodilation in response to acetylcholine and bradykinin, suggesting that this drug can improve endothelial function in patients with essential hypertension.

Acetylcholine↗

Transcapillary escape rate of albumin in type II diabetic patients. The relationship with microalbuminuria and hypertension.

OBJECTIVE: To study why in type II diabetes, microalbuminuria, a marker of generalized vascular dysfunction, and hypertension have been linked with both renal and cardiovascular organ damage. RESEARCH DESIGN AND METHODS: To investigate the effect of moderately elevated blood pressure on vascular damage, the transcapillary escape rate of albumin (TERalb) was measured by intravenous injection of purified 125I-human serum albumin in 9 healthy control subjects (group 1), 9 nondiabetic hypertensive subjects (group 2), and 73 nonobese type II diabetic patients stratified as follows: group 3: 17 normoalbuminuric-normotensive subjects; group 4: 22 normoalbuminuric-hypertensive subjects (systolic blood pressure [sBP] > or = 140 mmHg or diastolic blood pressure [dBP] > or = mmHg or both); group 5: 16 normotensive subjects with microalbuminuria (albumin excretion rate [AER]: 20-200 micrograms/min); and group 6: 18 microalbuminuric-hypertensive subjects. RESULTS: Groups 3-6 had similar age, sex, duration of diabetes (group 3: 7.8 +/- 5.5; group 4: 9.7 +/- 8.7; group 5: 12.1 +/- 8.1; and group 6: 10.7 +/- 8.3 years), BMI, HbA1c (7.8 +/- 1.1, 7.5 +/- 1.5, 8.7 +/- 1.5, and 7.7 +/- 1.1%, respectively), blood glucose, and lipid profile. Systolic and diastolic blood pressure did not differ in the three hypertensive group (group 2: 154 +/- 3/99 +/- 6; group 4: 149 +/- 13/95 +/- 6; group 6: 154 +/- 15/91 +/- 9 mmHg) and were significantly lower (P < 0.001) in group 3 (126 +/- 12/76 +/- 7), group 5 (128 +/- 11/77 +/- 5), and healthy control subjects (group 1: 133 +/- 7/81 +/- 4). TERalb was similar in control subjects (5.77 +/- 1.06%/h) and in normoalbuminuric-normotensive subjects (5.81 +/- 1.51%/h) but significantly higher (P < 0.0001) in microalbuminuric subjects with or without hypertension (9.11 +/- 1.65 and 8.60 +/- 1.50%/h, respectively) as well as in normoalbuminuric diabetic patients with hypertension (8.10 +/- 2.27%/h) and in essential hypertensive subjects (8.12 +/- 1.68%/h). CONCLUSIONS: By stepwise regression, TERalb was related (step 1) to log-AER (r = 0.30) or to the presence of microalbuminuria (r = 0.36) and (step 2) to dBP (multiple r = 0.40) or to the presence of hypertension (multiple r = 0.51) in the whole diabetic cohort (groups 3-6). TERalb was related to dBP (r = 0.47) or to the presence of hypertension (r = 0.56) only in normoalbuminuric diabetic patients (groups 3 and 4) and to log-AER (r = 0.56) or the presence of microalbuminuria (r = 0.68) only in normotensive patients (groups 3 and 5). In type II diabetic patients, TERalb was elevated in subjects with increased albuminuria, irrespective of blood pressure levels, but also was independently related to the presence of mild-to-moderate systemic hypertension.

Adult↗

Defective L-arginine-nitric oxide pathway in offspring of essential hypertensive patients.

BACKGROUND: Essential hypertension is characterized by impaired endothelium-dependent vasodilation. The present study was designed to investigate whether this abnormality is a primary defect or a consequence of blood pressure increases. METHODS AND RESULTS: In offspring of essential hypertensive patients (n = 34) and normotensive subjects (n = 30), we evaluated forearm blood flow (strain-gauge plethysmography) modifications induced by intrabrachial acetylcholine (0.15, 0.45, 1.5, 4.5, and 15 micrograms.100 mL-1.min-1), an endothelium-dependent vasodilator, and sodium nitroprusside (1, 2, and 4 micrograms.100 mL-1.min-1), an endothelium-independent vasodilator. Minimal forearm vascular resistances also were calculated as the ratio between mean intra-arterial pressure and maximal forearm blood flow induced by forearm ischemia and hand exercise. Vasodilation to acetylcholine was significantly (P < .01) blunted in offspring of hypertensive patients compared with offspring of normotensive subjects, whereas the responses to sodium nitroprusside and minimal forearm vascular resistances were similar. In two subgroups of 14 offspring of essential hypertensive patients but not in 10 offspring of normotensive subjects, vasodilation to acetylcholine was increased by intra-brachial L-arginine (1 mumol.100 mL-1.min-1), the substrate for nitric oxide synthesis, whereas in the other 10 and 8 offspring of essential hypertensive patients and normotensive subjects, respectively, cyclooxygenase blockade by intra-brachial indomethacin (50 micrograms.100 mL-1.min-1) was ineffective. CONCLUSIONS: Offspring of essential hypertensive patients are characterized by a reduced response to acetylcholine linked to a defect in the nitric oxide pathway, suggesting that an impairment in nitric oxide production precedes the onset of essential hypertension.

Acetylcholine↗

17-Hydroxyprogesterone response to ACTH in bilateral and monolateral adrenal incidentalomas.

The aim of our study was to assess the frequency of 21-hydroxylase deficiency, a cause of congenital adrenal hyperplasia (CAH), in incidentally discovered asymptomatic adrenal masses (incidentalomas) and to compare the prevalence of this enzymatic disorder in monolateral (M) and bilateral (B) forms. Twenty-seven patients with incidentalomas (12 M and 15 B) and 16 sex and age-matched controls (C) received synthetic adrenocorticotropin (ACTH, 250 micrograms i.v.). Plasma 17-OHprogesterone (17-OHP) and cortisol were collected in basal conditions and after 30, 60, 90 minutes. Basal plasma 17-OHP in C [1.25 +/- 0.15 (0.61) ng/ml, mean +/- SE (SD)] was not significantly different from that in patients with M [0.85 +/- 0.13 (0.44) ng/ml] or B [0.94 +/- 0.23 (0.90) ng/ml] incidentalomas. After ACTH, 17-OHP levels significantly (p < 0.05) increased in C, in M and B incidentalomas. However, the rise in plasma 17-OHP in C both in terms of peak [2.5 +/- 0.28 (1.1) ng/ml] and of AUC values [174 +/- 16 (64) ng/ml/min] was significantly lower than that observed in M [peak 6.32 +/- 1.66 (5.7) ng/ml, p < 0.01; AUC 410 +/- 111 (385.5) ng/ml/min, p < 0.01] and in B [peak 8.84 +/- 1.98 (7.65) ng/ml, p < 0.001; AUC 613 +/- 149 (579.3), ng/ml/min, p < 0.001] incidentalomas. Individual data indicated that while 17-OHP response to ACTH in C never reached 5 ng/ml (cut-off for normal response), 16 out of 27 patients with incidentalomas (59.2%) exceeded this value. Moreover, the abnormal response was more frequently observed in B (66.6%) than in M (50%) incidentalomas. Basal and stimulated plasma cortisol did not differ among the three groups. In conclusion, our data indicate that in adrenal incidentalomas the endocrine pattern of 21-hydroxylase deficiency is very common and that this enzymatic defect is more frequent in bilateral than in monolateral lesions.

17-alpha-Hydroxyprogesterone↗

Presence of cardiovascular structural changes in essential hypertensive patients with coronary microvascular disease and effects of long-term treatment.

In asymptomatic essential hypertensive patients with angiographically normal coronary arteries and without left ventricular hypertrophy, dipyridamole-induced ischemic-like ST segment depression may be a marker of coronary microvascular disease. In this study we evaluated, first, whether this cardiac abnormality is linked to structural or functional vascular abnormalities, and second, the effect of antihypertensive treatment by 12-month administration of the angiotensin converting enzyme (ACE) inhibitor captopril (50 mg twice a day orally). In essential hypertensives with dipypridamole echocardiography stress test (DET) (DET+, n = 8) and without (DET-, n = 8) ST segment depression greater than 0.1 mV during intravenous dipyridamole infusion (0.84 mg/kg over 10 min), we studied the forearm blood flow (FBF, venous plethysmography, mL/100) modifications induced by intrabrachial acetylcholine (Ach) (0.15, 0.45, 1.5, 4.5, 15 micrograms/100 mL/min x 5 min each), an endothelium-dependent vasodilator, and by sodium nitroprusside (SNP) (1, 2, 4 micrograms/100 mL/min x 5 min each), a smooth muscle cell relaxant compound. Minimal forearm vascular resistances (MFVR), an index of arteriolar structural changes, were also calculated. Both Ach and SNP caused greater vasodilation in DET- as compared to DET+ while MFVRs were lower in DET- compared to DET+. After treatment, both DET+ and DET- patients showed a significant and similar reduction in blood pressure and left ventricular mass index, while vasodilation to acetylcholine and sodium nitroprusside was increased only in the DET+ group. In addition, forearm minimal vascular resistances were significantly reduced only in DET+ patients, who showed disappearance of dipyridamole-induced ischemic-like ST segment depression. In conclusion, these data confirm that essential hypertensive patients with microvascular coronary disease are characterized by the presence of structural changes in the forearm vascular bed. Our results also indicate that both cardiac and forearm vascular abnormalities can be reversed by antihypertensive treatment with an ACE inhibitor.

Acetylcholine↗

Renovascular hypertension and insulin sensitivity.

We tested the hypothesis that the status of the renin-angiotensin-aldosterone system affects insulin sensitivity. Insulin sensitivity (by the euglycaemic insulin clamp technique) was measured in eight patients with angiographically proven renovascular hypertension and in eight normotensive subjects matched for age, gender, body mass index and glucose tolerance. In the patients, insulin sensitivity was measured both at baseline and following 7 days of ACE inhibition. Following glucose ingestion, patients and controls showed similar insulin and glucose responses. Insulin infusion (7 pmol min-1 kg-1) promoted similar glucose utilization in the hypertensives and normotensives: 24.8 +/- 2.3 vs. 26.0 +/- 3.0 mumol min-1 kg-1 respectively. One week of ACE inhibition caused a 20 +/- 4 mmHg decrease in mean blood pressure and a 20 +/- 6% decrease in peripheral vascular resistance. Plasma angiotensin II concentrations dropped from 24.6 +/- 6.3 to 13.5 +/-5.0 pg mL-1 (P < 0.05) and plasma aldosterone from 17 +/- 4 to 9 +/- 2 ng dL-1 (P < 0.05), and plasma renin activity doubled (from 1.6 +/- 0.3 to 3.4 +/- 1.7 ng mL-1 h-1, P < 0.02). Nevertheless, insulin sensitivity was unchanged (before, 24.8 +/- 2.3; after 25.8 +/- 2.2 mumol min-1 kg-1, P = Ns). During insulin infusion, forearm blood flow did not change from baseline in either set of studies. Also, the antinatriuretic (before, -26 +/- 18; after, -22 +/- 14%) and antikaliuretic (before: -36 +/- 13%, after -39 +/- 11%) action of the hormone was unaffected by the therapy. In conclusion, renovascular hypertension is not associated with insulin resistance. Furthermore, a selective, drastic reduction of the renin-angiotensin-aldosterone system activity and vascular tone does not alter insulin action on glucose and electrolyte metabolism.

Adult↗

Trough:peak ratio of nifedipine gastrointestinal therapeutic system and nifedipine retard in essential hypertensive patients: an Italian multicentre study.

OBJECTIVE: To evaluate the antihypertensive effect of nifedipine gastrointestinal therapeutic system and retard in terms of trough:peak ratio efficacy. METHODS: According to a double-blind, randomized, crossover design, 58 patients with mild-to-moderate essential hypertension, after 1 month placebo washout, received 30 mg/day nifedipine gastrointestinal therapeutic system, 20 mg nifedipine retard twice a day and the corresponding placebos for 1 month. At the end of each treatment period, blood pressure was measured by using a mercury sphygmomanometer at trough and 1, 2, 3 and 4 h after the last dosing. The peak effect was identified as the maximum decrement induced by the three randomized treatments with respect to the value at the end of the placebo washout period during the 4 h interval. The trough:peak ratios of systolic and diastolic blood pressure were calculated as group ratios and individual ratios from decrements induced by nifedipine gastrointestinal therapeutic system and retard, corrected for those induced by randomized placebo. Patients were defined as responders to each randomized treatment if their diastolic blood pressure at trough time was reduced by at least 10 mmHg relative to that at the corresponding time at the end of placebo washout. RESULTS: Nifedipine gastrointestinal therapeutic system and retard significantly reduced blood pressure to a similar extent both at trough and at peak. Systolic and diastolic group trough:peak ratios in responders to nifedipine gastrointestinal therapeutic system (n = 41) were 0.80 and 0.88, respectively, and those in responders to nifedipine retard (n = 30) 0.84 and 0.93, respectively. The percentage of patients with trough:peak ratios > 0.50 was > 80% (systolic trough:peak ratios) and above 90% (diastolic trough: peak ratios) for both nifedipine formulations. CONCLUSIONS: Our data show that 30 mg/day nifedipine gastrointestinal therapeutic system and 20 mg nifedipine retard twice a day have a favourable trough:peak ratios efficacy when given as monotherapy to essential hypertensive patients.

Adult↗

Menopause is associated with endothelial dysfunction in women.

To evaluate the effect of endogenous estrogens on endothelial function in humans, we examined whether menopause is associated with impairment in endothelium-dependent vasodilation in normotensive and essential hypertensive women. In 73 normotensive subjects (37 women, 36 men) and 73 hypertensive patients (36 women, 37 men), we studied endothelial function by measuring forearm blood flow modifications (strain-gauge plethysmography) induced by intrabrachial acetylcholine (0.15, 0.45, 1.5, 4.5, and 15 micrograms/100 mL per minute), an endothelium-dependent vasodilator, and sodium nitroprusside (1,2, and 4 micrograms/100 mL per minute), an endothelium-independent vasodilator. Women younger than 45 years had normal menstrual cycles. In essential hypertensive patients, responses to acetylcholine but not to sodium nitroprusside were significantly (P < .001) reduced compared with responses in normotensive subjects. Moreover, in both groups, vasodilation to acetylcholine showed a marked negative correlation with advancing age (normotensive subjects: r = -.88, P < .001; hypertensive patients: r = -.87, P < .001). In contrast, vasodilation to sodium nitroprusside showed a less evident negative correlation with advancing age (normotensive subjects: r = -46, P < .01; hypertensive patients: r = -.48, P < .01). However, in normally menstruating normotensive women, no endothelial dysfunction was observed, and age-related impairment in endothelium-dependent vasodilation was evident only after menopause. In normally menstruating hypertensive women, aging was associated with endothelial dysfunction although the deterioration of endothelium-dependent vasodilation was less marked than that in men. In contrast, after menopause, the age-related endothelial dysfunction in hypertensive women was similar to that observed in men. Finally, no sex-related difference in the response to sodium nitroprusside was observed in either normotensive subjects or essential hypertensive patients. Age-related endothelial dysfunction is attenuated in premenopausal normotensive and hypertensive women compared with men, whereas no sex-induced difference is observed after menopause, suggesting a protective effect of endogenous estrogens on endothelial function.

Acetylcholine↗

Cardiovascular characteristics in normotensive subjects with or without family history of hypertension.

The aim of our study was to evaluate whether initial changes of cardiovascular structure and/or function can be detected in young normotensive subjects with (F+) and without (F-) family history of hypertension. Thirty-two subjects (19 F+, 10 males and 9 females, age range 17-32 years; 13 F-, 6 males and 7 females, age range 19-33 years) were studied. In each subject 24 hours ambulatory blood pressure monitoring, a M-mode, 2d guided and pulsed doppler echocardiogram and postischemic forearm strain gauge plethysmography were performed. The two groups of subjects did not differ for causal systolic and diastolic BP and 24 hours systolic and diastolic ambulatory monitored blood pressure. No differences in LV end-diastolic and end-systolic diameters, as well as in LV wall thickness, and in LV mass index were observed. Systolic functional parameters were also similar in the two groups. In F+ subjects peak early filling velocity was reduced in respect to F- (p < 0.01), peak late filling velocity integral was increased (p < 0.05) and the ratio of peak E/peak A integrals was decreased (p < 0.05). No difference was observed for postischemic forearm blood flow and minimal vascular resistance, taken as an index of arteriolar structural changes as well as intima-media thickness of carotid arteries. In conclusion in this study F+ and F- had similar BP values, LV mass and min VR; differences previously observed in LV mass between F+ and F- may have been due to the presence of different basal levels of BP; in F+ LV diastolic filling, although still in the normal range, shifted early toward the pattern of LV filling usually observed in hypertensive patients.

Adult↗

Conventional and ambulatory blood pressure measurement in older patients with isolated systolic hypertension:second progress report on the ambulatory blood pressure monitoring project in the Syst-Eur trial.

OBJECTIVES: To compare clinic and ambulatory blood pressure measurement and the reproducibility of these measurements in older patients with isolated systolic hypertension.PATIENTS: A total of 477 patients aged >/= 60 years with isolated systolic hypertension on clinic measurement were monitored during the placebo run-in phase of the Syst-Eur trial. METHODS: The time-weighted 24 h blood pressure, clock time day and night blood pressure, the cumulative sum-derived crest and trough blood pressure and the high and low blood pressure levels of the square-wave model were computed. The daily alteration between the high and low blood pressure spans was quantified using the clock time day-night difference, the cumulative sum-derived circadian alteration magnitude, the Fourier amplitude and the difference between the high and low blood pressure levels of the square-wave model. RESULTS: The daytime ambulatory systolic blood pressure was, on average, 21 mmHg lower than the clinic blood pressure, whereasthe diastolic blood pressure was, on average, similar with both techniques of measurement. In the 132 patients who underwent repeat measurements, clinic blood pressure levels and the parameters describing the difference betgween the daily high and low blood pressure spans were equally reproducible. However, both were less reproducible than the ambulatory blood pressure levels. The repeatability coefficients, expressed as percentages of near maximum variation, were 50 and 51% for the clinic systolic and diastolic blood pressures, 30 and 33% for the mean 24 h systolic and diastolic blood pressures and between 44 and 54% for the parameters describing the daily alteration between the high and low blood pressure spans. CONCLUSION: In older patients with isolated systolic hypertension, clinic and ambulatory systolic blood pressure may differ greatly; the prognostic significance of this difference remains to be elucidated. Furthermore, the level of blood pressure in these patients is more reproducible by ambulatory measurement than it is by clinic measurement.

Journal Article↗

Lack of effect of percutaneous transluminal renal angioplasty on nocturnal hypotension in renovascular hypertensive patients.

OBJECTIVE: To investigate whether nocturnal blood pressure fall is blunted in renovascular hypertension and can therefore be used as a diagnostic criterion for this condition. METHODS: In 14 renovascular hypertensive patients (age 43.8+/-2.1 years, mean+/-SEM, clinic blood pressure 173.6+/-3.7 mmHg systolic and 109.0+/-2.0 mmHg diastolic) and in 14 age- and blood pressure-matched essential hypertensive controls 24 h ambulatory blood pressure was measured after washout from drug treatment, during angiotensin converting enzyme inhibitor treatment and, in renovascular hypertension, also after percutaneous transluminal renal angioplasty. RESULTS: The 24 h average systolic and diastolic blood pressures were 146.4+/-5.7 and 97.5+/-3.6 mmHg in renovascular and 144.3+/-1.2 and 98.0+/-2.2 mmHg in essential hypertensive patients. The angiotensin converting enzyme inhibitor treatment reduced 24 h average systolic and diastolic blood pressures by 8.5% and 9.7% in the renovascular and by 8.3% and 10.8% in the essential hypertensive group. Greater systolic and diastolic blood pressure reductions (-18.2% and -18.1%) were observed in renovascular hypertensive patients after percutaneous transluminal renal angioplasty. Blood pressure fell by about 10% during the night and the fall was similar in renovascular and in essential hypertensive patients. In the former group, nocturnal hypotension was similar after washout, during angiotensin converting enzyme inhibitor treatment and after percutaneous transluminal renal angioplasty. Similar results were obtained for nocturnal bradycardia. CONCLUSIONS: Nocturnal blood pressure fall is equally manifest in renovascular and essential hypertension. The removal of the renal artery stenosis and blood pressure normalization do not enhance this phenomenon. Nocturnal hypotension seems therefore to be unaffected by renovascular hypertension.

Adult↗

[Gene therapy in lysosomal diseases].

The study of the mechanisms of secretion and recapture of lysosomal enzymes has lead to the proposal of a treatment of lysosomal diseases by enzyme replacement. Autologous implants of genetically modified cells which secrete enzymes ensure systemic distribution of the lacking enzyme. A procedure which permits reimplantation of genetically modified fibroblasts is described. The stable secretion of human glucuronidase by autologous fibroblasts was thus obtained in animal species. This approach should by applicable to the treatment of Hurler's syndrome by obtaining the production and distribution of alpha-L-iduronidase in patients lacking this enzyme by retroviral transfer of the human alpha-L-iduronidase gene to cultured fibroblasts and by preparation of implants.

Animals↗