One-year isradipine treatment: Effects on diastolic function in hypertensive subjects with left ventricular hypertrophy

AIH-APRIL 1995-VOL.G, NO. 4, PART 2

74A ASH ABSTRACTS

D29 CALCIUM ANTAGONISTS AT HIGH ALTITUDE Erik Hanke and Morten Rostrup. Ulleval Hospital, Medical Department, University of Oslo, Oslo. Norway. The calciu m antagonist nifed ipine has been used in the t r eat ment of high altitude pulmonary edema. In t ~ e present study the effects of feloaip 1 n~ on blood pressure (BP) and cardiovascular responses to a cold pressor test were asses~ed at an altitude of 5200 m. 16 healthy climbers participatecl. A double blind randomized cross over design was used. Placebo or felodipine were taken for two days. There were no changes in blood pressure (mean±SD:125±15/89±13 vs. 127±17/86±15 mm "g), heart rate (82±12 VB. 81±lO beats/min) or oxygen saturation (86±3 vs 86±13%) during felodipine treatment compared to placebo. Moreover. there were no changes in the cardiovascular responses to the cold pressor test. We conclude that felodipine is well tolerated in young normotensive high altitude climbers. There are no effects on blood pressure or cardiovascular reactivity.

D30 EFFECT OF 'fREATMF.N'r WITH HVPOTENSIVE AND NON HYPOTENSIVE DOSE m' LAClDlPlNE ON STRUCTURAL ALTERATIONS OF SMALl. MESENTERIC ARTERIES OF SPONTANEOUSLY HYPERTENSIVE RUS. E, Poncri, D. Rizzoni . , M. Castellano ". G. Beuonl, A. Clnelll, M. Quartaroli #. E. Agabiti-Rosei ' . Chair of Scmelotlca e Metodologia Medica, U.O.P. Scienze Mediche, UniversilY ofBrescia and #I Gl8Jlo S.p.A., Verona, Italy. Lacidipine (LAC) i , i\ selective calcium entry-blocker drug which has been proved able to reduce "in vitro" smooth muscle cell proliferation. Aim of our sludy was to evaluate the modifications induced b)' LAC treatment on morphology of small mesenteric resistance vessels in spontaneously hypcrtensivc rats (SHR). LAC was administered at two different dosages. OI!e hypotensive (10 mglkgfdie) and one non hypotensive (l mg'kg'dle). Thirty-eight n:!.s were included in the study. Ten SHR and II WKY we.(; 1,';'1 untreated (w!:;. 1.1 SHR were treated with LAC high-dose (hd) and9 SHR with LAC low-dose (ld), Thedrug and tJu~ placebo were administered by gavage from 4 to 12 weeks of age. Blood pressure was mca~1Jrcd non invasivel.v every week, AI IJ weeks of age. animals were sacrificd bydecapitation. The heart was promptly dissected and weighed. and the relative left ventricular mass (RLVM: left ventricular plus septum wcightlbod)' weigh!} was calculated. Small mesenteric resistance vessels were dissected and mounted on a micromyograph (Mul\'any and Halpern technique). The foJlowing morphological parameters of the vessels were studied: media llJickness (MTI. normalized ir,temal diameter (ID), media/lumen ratio (MIL). Results were as follows: (·=p
Wit:\'I1IlI SURunt SUR lAC hd SURLACld

Mil.(%) 7.61:1.6·" l2.3i\ 9,2.±2.4 .. 12.2i2.2

MT (JlIl1)

RLVM (gIKg)

ID(!un)

sUP (mm Hg)

IG.2±2.2"· 22.4±3.1 19.4:1:1.9 • 26.5:<3.4

2.53:1:0.34 2.80:1:0.16 2,61:1:0.12' 266±0.12

217±31" 182:1:t9 223:1:55 • 222:1:38"

JS2:1:l3"· , 20:1:18 186:19"· 213:19

In conclusion. a significant regression of cardiovascular structural alterations was observed inthegroup of SHR treated with LAC hd, despite systolic blood pressure was notflllly normalized. Effective blood pressure rcduclion seems 10 be mandatory in order to obtain the regression of cardiovascular structural changes during treatment with LAC, as demonstrated bythclack of effects of thenon-hypotensive dose. Key Words: Calc i um an tagonis t s , high

altitude. hypoxia, cold pressor test

D31

KeyWords: Lacidipinc, SHR, vascular structural alterations,

D32

EARLY DIURETIC EF7ECT OF CALCIUM ANTAGONISTS IN ESSENTIAL HYPERTENSION. PT Scarpelli, R Livi, L Teghini, GM Caselli, L Di Maria, L Moscare11i, A Becucci, N Oi Cesare, E croppi, V Montemurro, and L Scarpelli. postgraduate School of Nephrology, Institute of Clinical Medicine IV, University of Florence, Florence, Italy. This 5t ~ jy was undertaken to investigate t~e causes of the obvious diuresis following within 60-90 mmut.es the oral assumption of a hypotensive dose of calcium antagonists. We have studied, in 8 untreated essential hypertensive patients, the early (within 90 minutes) changes in the inulin and PAH clearances and in (he urinary excretions of sodium, potassium, chloride, calcium, magnesium, phosphates and uric acid induced by a single oral dose of 20 mg of nitrendipine . I~easurements were carried out both at 100 and 350 mmol/die of sodium intake. Within stated time the only statistically significant change found was a 2 to 3-f01d increase of urinary volume. This early nitrendipine effect on free-water excretion occurred at 100 mmol/die sodium intake but not at 350 nunol/die. Our reSUlts suggest that low plasma concentration of nitrendipine may directly or indirectly prevent ADH effects. d

nitrendipine, inulin and PAH free-t"ater diuresis, ADH, essential hypertension.

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ONE-YEAR ISRADIPINE TREATMENT I EFFECTS ON DIASTOLIC FUNCTION IN HVPERTENSIVE SUBJECTS WITH LEFT VENTRICULAR HVPERTROPHV M. Galderisi', M. Garofalo, A. Alfieri, A. Petrocelli. A. Fakher. A. Izzo and O. de Divitiis. Clinical Methodology. "Feoerico II" University of Naples; ITALV. Our aim was to assess the effect of 10ngterm treatment with sustained-release isradipine (IS) on Doppler indexes of diastolic function and left ventricular (LV) mass in hypertension coMPlicated by LV hypertrophy (LVH). 10 subjects <5 M, 5 F, mean age 48 years) with mild-moderate hypertension and LVH (LV mass/height >141 glm in men and >101 giro in women) entered into a singleblind study. Doppler echocardiograms were carried out after 2 weeks of placebo run-in and after 12 Months of therapy w1th IS 5 mg once daily, IS reduced both systolIc and diastolic BP (p