Luciano Campanacci

Hepatitis C virus risk: a hepatitis C virus related syndrome

Abstract. Mazzaro C, Panarello G, Tesio F, Santini G, Crovatto M, Mazzi G, Zorat F, Tulissi P, Pussini E, Baracetti S, Campanacci L, Pozzato G (Pordenone General Hospital, Pordenone; University of Trieste, School of Medicine, Trieste, Italy). Hepatitis C virus risk: a hepatitis C virus‐related syndrome. J Intern Med 2000 247: 535–545.

Control of glomerular hyperfiltration and renal hypertrophy by an angiotensin converting enzyme inhibitor prevents the progression of renal damage in hypertensive diabetic rats.

OBJECTIVE Glomerular hyperfiltration and renal hypertrophy are both considered important in the progression of diabetic nephropathy. The aim of this study was to compare the effects of an equivalent reduction in blood pressure produced by the angiotensin-converting enzyme (ACE) inhibitor spirapril (SPI) and an antihypertensive triple drug combination of hydralazine, reserpine and hydrochlorothiazide (HRH) on kidney function, proteinuria and renal structure in hypertensive diabetic rats. DESIGN AND METHODS Four groups of animals were evaluated in short-term and long-term studies. In both studies one group served as a non-diabetic hypertensive control (H). The other three groups were rendered diabetic and were allocated to one of the following groups: the first diabetic group received no specific therapy (HD), the second diabetic group was treated with SPI (HD-SPI) and the third diabetic group was treated with HRH (HD-HRH). In each of the two studies the systolic blood pressure (SBP), 24 h urinary total protein, glomerular filtration rate (GFR), glomerular area, proximal tubular area and glomerular sclerosis were evaluated. RESULTS The blood pressure reduction was equal in rats receiving either SPI or HRH. The GFR, proteinuria, glomerular area and tubular area were significantly increased in the HD group, both in the short-term and the long-term study. In the HD-SPI group the diabetic hyperfiltration and renal hypertrophy responses were prevented. In the HD-HRH group the GFR and proteinuria were slightly reduced in the later phases of diabetes, while the glomerular area and tubular area were not affected. Semiquantitative analysis of renal lesions showed that SPI was more effective than HRH in the prevention of the development of glomerulosclerosis. CONCLUSIONS The results of this study suggest that the control of early adaptive hyperfiltration and renal hypertrophy by SPI may be relevant in the prevention of glomerulosclerosis.

Peripheral adrenoceptors in hypotension of hemodialyzed uremic patients.

Hypotension is a common problem in patients on hemodialysis. To further investigate this problem, the number of platelet alpha 2-adrenoceptors and the activity of lymphomonocyte beta 2-adrenoceptors were measured in 10 hemodialyzed patients with normal blood pressure and in 10 sex- and age-matched persistently hypotensive hemodialyzed patients. Density of alpha 2-adrenoceptors was assessed by the specific binding of 3H-yohimbine to intact platelets, while the function of beta 2-adrenoceptors was estimated by the production of cAMP after the exposure of lymphomonocytes to isoprenaline. The maximal number of alpha 2-adrenoceptors was increased in the hypotensive compared to the normotensive group (262.13 vs. 77.21 fmol/mg protein; p < 0.01). Plasma norepinephrine was higher in the hypotensive than in the normotensive uremic patients (640 +/- 195 vs. 344 +/- 156 pg/ml; p < 0.01). Plasma epinephrine did not differ in the two groups (90 +/- 30 vs. 94 +/- 24 pg/ml). The amount of cAMP, produced by stimulation of lymphomonocytes, was lower in the hypotensive than that in the normotensive uremic patients (7.7 +/- 2.4 vs. 15.6 +/- 5.4 pmol/10(6) cells; p < 0.002). The increased number of alpha 2-adrenoceptors together with a high level of norepinephrine and reduced activity of adenylate cyclase (coupled with beta 2-adrenoceptors) support the hypothesis that hypotension in the hemodialyzed uremic patients may be related to a defect in adrenoceptor coupling mechanisms.

Regional hemodynamic effects of slow-release nicardipine in elderly patients with hypertension: Evaluation by a new ultrasound technique

Blood flow in superficial vessels was measured by means of combined two-dimensional and continuous-wave Doppler echography. In vitro validation of the technique showed precision to within 10% at flow rates greater than 300 ml/min. Assessment of common carotid artery blood flow was used to calculate vascular resistance in a single-blind, crossover study of 16 elderly patients over the age of 60 years (mean 67.7 +/- 6.5) with essential hypertension. The pulsatility index of the brachial artery was also determined. Before the study patients had previously received either placebo (twice a day) for 2 weeks or slow-release (SR) nicardipine (40 mg twice a day) for 2 months. During the study patients received a single 40 mg dose of nicardipine SR, after which mean arterial blood pressure decreased from 131 +/- 11 to 110 +/- 10 mm Hg (p less than 0.001) and from 122 +/- 13 to 108 +/- 11 mm Hg (p less than 0.001) in patients who had previously received placebo and nicardipine, respectively. Carotid vascular resistance decreased from 14.6 +/- 2.9 to 10.4 +/- 2.8 mm Hg.sec.ml-1 (p less than 0.001) and from 14.6 +/- 4.1 to 11.0 +/- 2.0 mm Hg.sec.ml-1 (p less than 0.01), respectively. The pulsatility index of the brachial artery changed from 9.4 +/- 4.4 to 9.7 +/- 8.3 and from 8.2 +/- 4.3 to 9.4 +/- 4.1, respectively (not significant). These data show that nicardipine SR reduces resistance both in the common carotid artery and in the brachial artery. Furthermore this drug appears to have an additional effect on the distensibility of the large arteries.

Effects of Rilmenidine and Hydrochlorothiazide on Human Platelet α2-Adrenoceptors

SummaryThis study was designed to better characterise in humans the mechanism of action of rilmenidine, a new antihypertensive oxazoline derivative. The functional relationship between hypotensive response, adrenergic nerve activity and platelet α2-adrenoceptor number and function was evaluated in hypertensive subjects, both before and after prolonged treatment with this drug. The effects of rilmenidine were compared with those induced by a diuretic drug (hydrochlorothiazide). After 1 month of placebo, 24 patients with essential hypertension were randomly allocated to either rilmenidine 1mg once daily or hydrochlorothiazide 25mg once daily. At the end of the first month of treatment, the 2 drugs were combined in the patients whose diastolic blood pressure was higher than 90mm Hg. On days 0, 30 and 60, the number and affinity of blood platelet α2-adrenoceptors were measured by 3H-yohimbine labelling, and plasma catecholamines were determined. On days 0 and 30, platelet aggregation was also assessed.The results show that the administration of rilmenidine exerts significant and lasting antihypertensive activity. This effect, however, is not associated with a modification in platelet α2-adrenoceptor density and function, nor does it seem to affect catecholamine plasma levels, thus suggesting a negligible role for α2-adrenoceptor stimulation in the antihypertensive action of rilmenidine.