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Castellano M, Rizzoni D, Beschi M, Böhm M, Porteri E, Bettoni G, Cinelli A, Rosei EA. Chronic ACE-inhibitor treatment and adrenergic mechanisms in spontaneously hypertensive rats. J Cardiovasc Pharmacol 1995; 26:381-7. [PMID: 8583778 DOI: 10.1097/00005344-199509000-00006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We investigated the effects of chronic treatment with the angiotensin-converting enzyme (ACE) inhibitor fosinopril on cardiac and vascular noradrenergic neurotransmission as related to cardiovascular hypertrophy in spontaneously hypertensive rats (SHRs). SHRs were treated with fosinopril at "high dose" (SHR-HD, 25 mg/kg/day) or "low dose" (SHR-LD, 1 mg/kg/day) from the 6th to the 12th week of age, and compared to age-matched untreated SHRs (SHR-C) and Wistar-Kyoto controls (WKY). Blood pressure was significantly reduced in SHR-HD but not in SHR-LD when compared to SHR-C. The antihypertensive dose of fosinopril reduced both cardiac and vascular hypertrophy, whereas the low dose was effective only in reducing vascular hypertrophy. Several differences in presynaptic and postsynaptic cardiovascular noradrenergic neurotransmission were observed between SHR-C and WKY rats (increased cardiac norepinephrine concentration, down-regulation of cardiac beta-adrenoceptors, reduced alpha-adrenergic receptor-mediated vasoconstrictor response of small mesenteric arteries to exogenous norepinephrine). All these differences were abolished by ACE inhibitor treatment, both at antihypertensive or at subantihypertensive doses. The results of this study are consistent with the hypothesis that chronic ACE inhibition may exert an inhibitory modulation on the peripheral adrenergic transmission, which is not related to blood pressure reduction. This modulation does not appear to be a determinant in preventing the development of cardiac hypertrophy but may play a role in the regression of vascular structural alterations in spontaneously hypertensive rats.
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MESH Headings
- Analysis of Variance
- Angiotensin-Converting Enzyme Inhibitors/administration & dosage
- Angiotensin-Converting Enzyme Inhibitors/pharmacology
- Angiotensin-Converting Enzyme Inhibitors/therapeutic use
- Animals
- Blood Pressure/drug effects
- Cardiomegaly/prevention & control
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Down-Regulation
- Fosinopril/administration & dosage
- Fosinopril/pharmacology
- Fosinopril/therapeutic use
- Hypertension/drug therapy
- Mesenteric Arteries/drug effects
- Mesenteric Arteries/metabolism
- Myocardium/pathology
- Norepinephrine/metabolism
- RNA, Messenger/metabolism
- Radioligand Assay
- Rats
- Rats, Inbred SHR
- Rats, Inbred WKY
- Receptors, Adrenergic, alpha/drug effects
- Receptors, Adrenergic, alpha/metabolism
- Receptors, Adrenergic, beta/drug effects
- Receptors, Adrenergic, beta/genetics
- Receptors, Adrenergic, beta/metabolism
- Ribonucleases/chemistry
- Synaptic Transmission/drug effects
- Vascular Resistance/drug effects
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Rizzoni D, Castellano M, Porteri E, Bettoni G, Muiesan P, Muiesan ML, Giulini SM, Cinelli A, Salvetti M, Agabiti Rosei E. Arterial spontaneous rhythmic contractile activity in humans and rats: spectral analysis and regulatory mechanisms. J Hypertens 1995; 13:1043-52. [PMID: 8586823 DOI: 10.1097/00004872-199509000-00016] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE Many experimental observations have demonstrated the presence of spontaneous cyclic vasomotor activity (CVA) in large and small arteries. This study aimed to evaluate the characteristics of spontaneous CVA in rat and human resistance arteries, and to investigate its possible interference with the evaluation of sympathetic activity by means of spectral analysis of blood pressure in vivo. DESIGN AND RESULTS In study 1 we examined small mesenteric arteries of spontaneously hypertensive rats and Wistar-Kyoto rats, as well as small omental arteries of normotensive subjects and hypertensive patients (Mulvany and Halpern technique). CVA was enhanced by the agonists of nitric oxide release, and was abolished by the inhibitors of nitric oxide or cyclic GMP synthesis. A potassium channel, which is barium- and zinc-sensitive and tetraethylammonium-insensitive, seems to play a crucial role in the genesis of CVA. In rats and in humans the frequency of CVA fell exactly in the frequency band ('low frequencies') of power spectral analysis of blood pressure usually considered to be an 'index of sympathetic activity'. In study 2, a power spectral analysis of blood pressure variability before and after intra-arterial infusion of noradrenaline or acetylcholine was performed in 18 patients with mild-to-moderate hypertension. The absolute and normalized spectral power of the low-frequency systolic blood pressure peak increased remarkably after noradrenaline and acetylcholine infusion, while its central frequency shifted from 0.10 Hz to approximately 0.06 Hz, exactly the frequency of CVA observed in vitro. CONCLUSIONS A potassium channel appears to be involved in the genesis of CVA. Also, CVA might contribute to the blood pressure variability independently of the autonomic nervous system activity, and thus probably plays a role in the genesis of the low-frequency peak in the rat and in humans.
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Rizzoni D, Castellano M, Porteri E, Bettoni G, Muiesan ML, Cinelli A, Rosei EA. Effects of low and high doses of fosinopril on the structure and function of resistance arteries. Hypertension 1995; 26:118-23. [PMID: 7607714 DOI: 10.1161/01.hyp.26.1.118] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
It has been suggested that angiotensin-converting enzyme inhibitors may induce a significant regression of cardiovascular hypertrophy not only through blood pressure reduction but also as a possible consequence of growth factor inhibition. The aim of this study was to evaluate the effects of the angiotensin-converting enzyme inhibitor fosinopril, given either at a hypotensive high dose or a nonhypotensive low dose, on structural and functional alterations of mesenteric resistance arteries and on cardiac mass in spontaneously hypertensive rats (SHR) and control Wistar-Kyoto rats. Fosinopril was administered in the drinking water from 6 to 12 weeks of age. Rats were killed at 12 weeks, and the ratio of heart weight to body weight was measured. Mesenteric arterioles were dissected and mounted on a micromyograph (Mulvany's technique). Vascular morphology (media-lumen ratio, media thickness) and endothelial function (response to acetylcholine) were then assessed. During the 6 weeks of treatment, systolic pressure in SHR treated with high-dose fosinopril was significantly lower compared with that in untreated SHR, whereas no difference was observed with low-dose fosinopril. In SHR treated with both high-dose and low-dose fosinopril, a statistically significant reduction of vascular structural alterations, in terms of both media-lumen ratio and media thickness, was observed. The ratio of heart weight to body weight was reduced only in SHR treated with high-dose fosinopril. An improvement in the endothelium-dependent relaxation to acetylcholine was observed in SHR treated with high-dose fosinopril compared with untreated SHR, whereas in SHR treated with low-dose fosinopril no improvement in endothelial function was detected.(ABSTRACT TRUNCATED AT 250 WORDS)
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Castellano M, Muiesan ML, Rizzoni D, Beschi M, Pasini G, Cinelli A, Salvetti M, Porteri E, Bettoni G, Kreutz R. Angiotensin-converting enzyme I/D polymorphism and arterial wall thickness in a general population. The Vobarno Study. Circulation 1995; 91:2721-4. [PMID: 7758176 DOI: 10.1161/01.cir.91.11.2721] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND It has been reported that the D allele of an insertion/deletion (I/D) polymorphism of the angiotensin I-converting enzyme (ACE) gene is associated with conditions of increased cardiovascular risk, including left ventricular hypertrophy. METHODS AND RESULTS Considering that a genetically determined overactivity of the renin-angiotensin system may influence cardiac as well as vascular growth, we investigated possible relations between ACE I/D genotype and carotid artery wall thickness (B-mode ultrasound) in 199 subjects, 50 to 64 years old, sampled from the general population of Vobarno, a small town in northern Italy. ACE DD genotype was associated with significantly higher common carotid artery intima-media thickness (P = .003). The occurrence of carotid atherosclerotic plaques was similar in the different genotypes. There was no association of the ACE I/D genotype with blood pressure values (either casual of 24-hour ambulatory monitored). CONCLUSIONS ACE DD genotype may be considered a risk factor for the development of common carotid intima-media thickening in our study population.
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Carotti A, Altomare C, Cellamare S, Monforte A, Bettoni G, Loiodice F, Tangari N, Tortorella V. LFER and CoMFA studies on optical resolution of alpha-alkyl alpha-aryloxy acetic acid methyl esters on DACH-DNB chiral stationary phase. J Comput Aided Mol Des 1995; 9:131-8. [PMID: 7608744 DOI: 10.1007/bf00124403] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The HPLC resolution of a series of racemic alpha-substituted alpha-aryloxy acetic acid methyl esters I on a pi-acid N,N'-(3,5-dinitrobenzoyl)-trans-1,2-diaminocyclohexane as chiral selector was modelled by linear free energy-related (LFER) equations and comparative molecular field analysis (CoMFA). Our results indicate that the retention process mainly depends on solute lipophilicity and steric properties, whereas enantioselectivity is primarily influenced by electrostatic and steric interactions. CoMFA provided additional information with respect to the LFER study, allowed the mixing of different subsets of I and led to a quantitative 3D model of steric and electrostatic factors responsible for chiral recognition.
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Rosei EA, Rizzoni D, Castellano M, Porteri E, Zulli R, Muiesan ML, Bettoni G, Salvetti M, Muiesan P, Giulini SM. Media: lumen ratio in human small resistance arteries is related to forearm minimal vascular resistance. J Hypertens 1995; 13:341-7. [PMID: 7622856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND For the evaluation in humans of structural alterations in resistance arteries, most studies have used an indirect index, the measurement of minimal vascular resistance (mean blood pressure divided by maximal postischaemic blood flow) in suitable vascular beds. A sensitive and specific micromyographic technique was recently made available for the study of human small resistance arteries. Whether a correlation really exists between results obtained with the two techniques has not yet been investigated. OBJECTIVE To evaluate both forearm minimal vascular resistance and media:lumen ratio of omental or subcutaneous small arteries in normotensive subjects and hypertensive patients. DESIGN AND METHODS Thirty-four individuals were included in the study (age range 35-74 years; 24 hypertensive, 10 normotensive). Twenty-five had elective abdominal surgery and nine hypertensive patients had a gluteal biopsy. Omental and subcutaneous small arteries were dissected and mounted on a wire micromyograph (Mulvany's technique), and media:lumen ratio and media thickness were measured. The dose-response curve to noradrenaline was constructed at cumulative concentrations from 3 x 10(-9) to 3 x 10(-5) mol/l. Venous occlusion plethysmography was used to measure blood flow in the forearm, and minimal vascular resistance was calculated from mean blood pressure and postischaemic maximal blood flow (13 min ischaemia plus exercise). RESULTS A statistically significant correlation was found between media:lumen ratio and minimal vascular resistance (r = 0.74, P < 0.001) as well as between media:lumen ratio and systolic (r = 0.44, P < 0.01) and diastolic (r = 0.38, P < 0.05) blood pressures. Similar correlations were observed between media thickness and systolic and diastolic blood pressures. Small arteries from hypertensive patients had a significantly increased reactivity to noradrenaline (by analysis of variance) compared with those from normotensive subjects, in terms of wall tension but not of active media stress. CONCLUSIONS The present study demonstrated that the media:lumen ratio of small resistance vessels is significantly related to forearm minimal vascular resistance, suggesting that direct and indirect evaluations of vascular morphology will give similar results.
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Rizzoni D, Castellano M, Porteri E, Bettoni G, Muiesan ML, Agabiti Rosei E. Delayed development of hypertension after short-term nitrendipine treatment. Hypertension 1994; 24:131-9. [PMID: 8021001 DOI: 10.1161/01.hyp.24.1.131] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In this study we evaluated the delayed effects of a calcium entry blocker on blood pressure and on vascular structural and functional alterations in mesenteric resistance arteries of spontaneously hypertensive rats (SHR). The calcium entry blocker nitrendipine was administered (30 mg/kg per day) according to three different schedules: in one group of SHR from 4 to 8 weeks of age (n = 12), in a second group from 8 to 12 weeks of age (n = 12), and in a third group from 4 to 12 weeks of age (n = 12). Twelve untreated SHR and 12 untreated Wistar-Kyoto rats served as controls. Half the animals of each group were killed at 13 weeks, and the remaining were killed at 38 weeks. After death, relative left ventricular mass was calculated. Vascular morphology and function (responses to norepinephrine and acetylcholine) in mesenteric small arteries were then assessed using a micromyographic technique. Nitrendipine treatment delayed the development of hypertension and determined the regression of structural alterations of mesenteric resistance arteries in SHR. These favorable effects were maintained for several weeks after treatment withdrawal, provided that treatment was started at 4 weeks of age. Considering the functional alterations of mesenteric arteries in SHR (responses to norepinephrine and acetylcholine), nitrendipine treatment determined an improvement of both these dysfunctions as long as reductions of the media-to-lumen ratio and blood pressure, respectively, were maintained.
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Rizzoni D, Castellano M, Porteri E, Bettoni G, Muiesan ML, Agabiti-Rosei E. Vascular structural and functional alterations before and after the development of hypertension in SHR. Am J Hypertens 1994; 7:193-200. [PMID: 8179854 DOI: 10.1093/ajh/7.2.193] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The time-course of the development of vascular and cardiac hypertrophy, as well as of arterial dysfunction, in human and experimental hypertension is still unclear. Moreover, the interrelationships between structural and functional vascular alterations are presently under debate. The aim of this study was to assess the arteriolar wall thickness and left ventricular mass as well as the vascular response to norepinephrine and acetylcholine in spontaneously hypertensive rats (SHR), before and after the development of hypertension, as compared to age-matched normotensive Wistar-Kyoto rats (WKY). Seventeen SHR (4 to 12 weeks old) and 17 WKY were included in the study. Blood pressure was measured noninvasively. After killing the animals, relative left ventricular mass (RLVM) was calculated, and mesenteric arcades were dissected and mounted on a micromyograph. Functional and structural characteristics of the vessels were measured: media thickness (MT), media/lumen ratio (M/L), and wall tension in response to norepinephrine and acetylcholine. At 4 weeks of age, no difference in blood pressure and RLVM between SHR and WKY was detected, but MT and M/L of mesenteric small resistance arteries were significantly greater in SHR. An increased response to norepinephrine was observed in terms of wall tension, but not of active media stress at the two higher norepinephrine concentrations. No difference in the dose-response curve to acetylcholine between SHR and WKY was observed. At 8 and 12 weeks of age systolic blood pressure was significantly higher in SHR; RLVM, MT, and M/L were also higher at this stage.(ABSTRACT TRUNCATED AT 250 WORDS)
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Rizzoni D, Porteri E, Castellano M, Bettoni G, Salvetti M, Agabiti-Rosei E. Early treatment with nitrendipine may prevent endothelial dysfunction in mesenteric small arteries of spontaneously hypertensive rats. JOURNAL OF HYPERTENSION. SUPPLEMENT : OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF HYPERTENSION 1993; 11:S360-S361. [PMID: 8158422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Castellano M, Paul M, Beschi M, Bachmann J, Rizzoni D, Porteri E, Bettoni G, Cinelli A, Ganten D, Agabiti-Rosei E. Gene regulation of beta-1-adrenergic receptor in genetically hypertensive rats. JOURNAL OF HYPERTENSION. SUPPLEMENT : OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF HYPERTENSION 1993; 11:S64-5. [PMID: 8158436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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36
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Castellano M, Beschi M, Rizzoni D, Paul M, Böhm M, Mantero G, Bettoni G, Porteri E, Albertini A, Agabiti-Rosei E. Gene expression of cardiac beta 1-adrenergic receptors during the development of hypertension in spontaneously hypertensive rats. J Hypertens 1993; 11:787-91. [PMID: 8228201 DOI: 10.1097/00004872-199308000-00004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE To study adrenergic receptors in the heart tissues of genetically hypertensive rats by evaluating the gene expression and the membrane protein density of beta 1-adrenergic receptors using steady-state messenger RNA (mRNA) levels and a radioligand binding assay, respectively. DESIGN We compared prehypertensive (5-week-old) and early-hypertensive (13-week-old) spontaneously hypertensive rats (SHR) with age-matched Wistar-Kyoto (WKY) normotensive control rats. METHODS Polyadenylated RNA was extracted from individual hearts and analysed by the slot-blot technique using a beta 1-adrenergic receptor complementary DNA probe. beta-Adrenergic receptors in myocardial membranes were studied by radioligand binding assay using [125I]-cyanopindolol and the beta 1- and beta 2-selective antagonists CGP 207.12A and ICI 118.551, respectively. RESULTS beta 1-Adrenergic receptor mRNA levels were slightly higher, and membrane protein density was similar in prehypertensive SHR and age-matched WKY rats. However, both beta 1-adrenergic receptor mRNA levels and beta 1-adrenergic receptor density were lower in the hypertensive SHR than in the control rats. beta 1-Adrenergic receptor mRNA was significantly reduced in older rats of both strains, and this reduction was most evident in the SHR. CONCLUSIONS The absence of downregulation of beta 1-adrenergic receptors in young SHR, despite published data indicating a higher cardiac noradrenaline turnover than in WKY rats, may suggest that the cardiac hyperadrenergic activity observed in prehypertensive SHR is maintained, at least in part, by the participation of peripheral, postsynaptic component(s) involving beta 1-adrenergic receptor dysregulation. In addition, the present data suggest that the previously reported evidence of an age-related decrease in cardiac beta 1-adrenergic receptors in rats may be determined at the transcriptional level.
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Rizzoni D, Muiesan ML, Zulli R, Castellano M, Bettoni G, Porteri E, Agabiti-Rosei E. Effect of antihypertensive treatment on daytime and nighttime power spectral analysis of heart rate. Am J Hypertens 1993; 6:204-8. [PMID: 8466707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Power spectral analysis of heart rate may provide useful information about cardiac neural activity. The aim of this study was to evaluate cardiac sympathetic and parasympathetic activity, as assessed by power spectral analysis of heart rate, in hypertensive patients before and after antihypertensive treatment. In 14 hypertensive patients and in 7 normotensive subjects 24 h Holter electrocardiogram monitoring was performed under basal conditions and after 6 months of treatment with nifedipine (n = 7) or enalapril (n = 7). Sequences of 512 RR intervals were taken for the evaluation of power spectral analysis (autoregressive method); absolute and normalized power spectral density of the peak at 0.10 Hz (low frequency peak: LF) and at 0.25 Hz (high frequency peak: HF), as well as their ratio (index of sympatovagal interaction: SVI) were calculated. Under basal conditions SVI was significantly decreased from daytime to nighttime in normotensives, while no change was observed in hypertensive patients. In all hypertensive patients a reduction of SVI during nighttime in respect to basal values was observed after treatment. SVI during nighttime was significantly reduced with both nifedipine and enalapril, while SVI during daytime was slightly increased during nifedipine treatment, and significantly reduced during enalapril treatment. Systolic and diastolic arterial pressure as well as left ventricular mass index were significantly reduced with both treatments. In conclusion, long term treatment with nifedipine or enalapril seems to be able to restore an impaired daytime to nighttime SVI modulation in hypertensive patients, even considering the potential limitations of power spectral analysis of heart rate.
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Loiodice F, Ferorelli S, Tangari N, Bettoni G, Tortorella V, Pierno S, De Luca A, Tricarico D, Conte-Camerino D. Carboxylic acids and chloride conductance in skeletal muscle: influence on the pharmacological activity induced by the chain substituents and the distance between the phenolic group and the carboxylic function in 4-chloro-phenoxy alkanoic acids. FARMACO (SOCIETA CHIMICA ITALIANA : 1989) 1993; 48:45-63. [PMID: 8384454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Some analogues of 2-(4-chloro-phenoxy)-propionic acid have been synthesized to evaluate the influence on the skeletal muscle chloride conductance of the distance between the phenolic and the carboxylic groups and/or the presence of substituents and chiral centers differently located on the carbon chain. Absolute configuration and/or chiroptical properties of the chiral compounds synthesized have been determined. These compounds, differently from fibrates, show a very low activity on chloride conductance and no remarkable correlation of this parameter with the absolute configuration.
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Bortone E, Bettoni G, Giorgi C, Murgese A, Stocchetti M, Mancia D. Adult postanoxic "erratic" status epilepticus. Epilepsia 1992; 33:1047-50. [PMID: 1464262 DOI: 10.1111/j.1528-1157.1992.tb01757.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A 66-year-old woman with posttraumatic anoxic coma after diffuse cerebral fat embolism had continuous alternating-side myoclonic jerks. Usually, this kind of myoclonic status epilepticus (SE) occurs in newborn infants. We postulate the unusual combination of diffuse cerebral anoxia plus commissural fiber damage as a possible explanation.
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Bettoni G, Ferorelli S, Loiodice F, Tangari N, Tortorella V, Gasparrini F, Misiti D, Villani C. Chiral ?-substituted ?-aryloxy acetic acids: Synthesis, absolute configuration, chemical resolution, and direct separation by hplc. Chirality 1992. [DOI: 10.1002/chir.530040311] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Rizzoni D, Castellano M, Beschi M, Muiesan ML, Bettoni G, Porteri E, Agabiti-Rosei E. Plasma norepinephrine and spectral analysis of the heart rate during cardiopulmonary receptor stimulation in normal and hypertensive subjects. JOURNAL OF HYPERTENSION. SUPPLEMENT : OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF HYPERTENSION 1991; 9:S84-5. [PMID: 1819021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Conte Camerino D, Tortorella V, Bettoni G, Bryant SH, De Luca A, Mambrini M, Tricarico D, Grasso G. A stereospecific binding site regulates the C1- ion channel in rat skeletal muscle. PHARMACOLOGICAL RESEARCH COMMUNICATIONS 1988; 20:1077-8. [PMID: 2463645 DOI: 10.1016/s0031-6989(88)80734-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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43
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Conte-Camerino D, Mambrini M, DeLuca A, Tricarico D, Bryant SH, Tortorella V, Bettoni G. Enantiomers of clofibric acid analogs have opposite actions on rat skeletal muscle chloride channels. Pflugers Arch 1988; 413:105-7. [PMID: 2464159 DOI: 10.1007/bf00581238] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The S-(-) isomers of a series of clofibric acid analogs produced only a block of chloride conductance of rat skeletal muscle fibers with increasing concentrations until block was nearly complete. The R-(+) isomers, on the other hand, at low concentrations increased chloride conductance by as much as 9% to 39% and at higher concentrations decreased chloride conductance, but never by more than 27% of the control value. The actions of the enantiomeric pairs to either produce or inhibit myotonic excitability paralleled their ability to block or increase chloride conductance, respectively.
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Perrone R, Berardi F, Bettoni G, Tortorella V. Dopamine receptor agonists: new angularly annulated tricyclic compounds. IL FARMACO; EDIZIONE SCIENTIFICA 1988; 43:61-9. [PMID: 3396689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In order to study the influence on dopaminergic activity of the exchange of X in rigid dopamine congeners of structure 1, the synthesis of octahydrobenzo [f] trans-quinoxalines (VII c, d) and trans-hexahydro-4H-naphtho[1,2-b][1,4]thiazines (X c, d), is reported.
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Perrone R, Berardi F, Bettoni G, Tortorella V. Synthesis of new linearly annulated tricycles as rigid dopamine congeners. IL FARMACO; EDIZIONE SCIENTIFICA 1988; 43:71-7. [PMID: 3396690 DOI: 10.1002/chin.198834196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A simple synthetic route that leads to three isosters of octahydrobenzo[g]quinolines (IA), in which the carbon atom in 4-position is replaced by an oxygen, a sulfur or a nitrogen atom, to give hexahydronaphth-[1,4]oxazine (VIII a) and -[1,4]thiazine (VIII b), and octahydrobenzo[g]quinoxaline (VIII c) respectively, is here reported. These compounds can be considered as new structural models of dopamine agonists.
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Feller DR, Kamanna VS, Newman HA, Romstedt KJ, Witiak DT, Bettoni G, Bryant SH, Conte-Camerino D, Loiodice F, Tortorella V. Dissociation of hypolipidemic and antiplatelet actions from adverse myotonic effects of clofibric acid related enantiomers. J Med Chem 1987; 30:1265-7. [PMID: 2441050 DOI: 10.1021/jm00391a001] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Enantiostructure-activity studies of chlorophenoxybutyric and propionic acids have provided evidence for the dissociation of serum cholesterol lowering and platelet antiaggregatory activities from the adverse chloride ion channel mediated myotonic effects of these compounds. R-(+) propionic and butyric acid enantiomers, unlike achiral clofibric acid and the S-(-) isomers, did not inhibit chloride conductance in rat extensor digitorum longus muscle fibers in vitro but, like clofibric acid and the S-(-) isomers, retained the serum cholesterol lowering activity in a cholesterol-fed rat model. Additionally, a stereoselective and greater inhibition was observed for the R-(+) isomers against adenosine diphosphate and arachidonic acid induced human platelet aggregation.
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Bettoni G, Loiodice F, Tortorella V, Conte-Camerino D, Mambrini M, Ferrannini E, Bryant SH. Stereospecificity of the chloride ion channel: the action of chiral clofibric acid analogues. J Med Chem 1987; 30:1267-70. [PMID: 2441051 DOI: 10.1021/jm00391a002] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
2-(p-Chlorophenoxy)isobutyric acid (clofibric acid (1) or CPIB) is a drug known to block chloride membrane conductance (GCl) in rat striated muscle. In the present study chiral analogues of CPIB (2-(p-chlorophenoxy)propionic acid (2) and 2-(p-chlorophenoxy)butyric acid (3)) have been tested to evaluate the influence of chirality on Cl ion flux in the channel. The results showed that the chloride channel conductance strongly depends on the absolute configuration: in fact, the S-(-) isomers of the tested compounds strongly decreased the GCl of skeletal muscle membrane, whereas the R-(+) isomers were virtually ineffective. These data allow the hypothesis that, like other ion channels present in various biological systems, the chloride channel of skeletal muscle membrane could also have a stereospecific binding site (or receptor) regulating chloride ion flux.
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Bettoni G, Catsiotis S, Franchini C. [Studies on the chiroptical properties of 2,4-dinitrophenyl derivatives of amino compounds of pharmaceutical interest]. IL FARMACO; EDIZIONE SCIENTIFICA 1977; 32:367-74. [PMID: 862893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Some results on the chiroptical properties of 2,4-dinitrophenylaminoacids reported in the literature, have been re-examined since they were in disagreement with our earlier research. Extension of this research to several sympathomimetic amines, demonstrates that the chiroptical properties of these derivatives show coherent behaviour; as a consequence the absolute configuration of the amino compounds condensed with Sanger reagent can be correlated to the sign of their higher wavelength Cotton effect.
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Bettoni G, Franchini C. [Indirect quantitative determination of quaternary ammonium compounds of high molecular weight by means of ion exchange chromatography]. IL FARMACO; EDIZIONE PRATICA 1976; 31:420-5. [PMID: 955055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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50
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Bettoni G, Franchini C. [Determination of absolute configuration of amine compounds of pharmaceutical interest by means of measurement of circular dichroism]. IL FARMACO; EDIZIONE SCIENTIFICA 1976; 31:105-11. [PMID: 1261661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The CD curves study of the pyridyl-N-oxide derivatives of some adrenergic and anorexigenic amines showed that the sign of the Cotton effect can be related to their absolute configuration. The obtained results confirm the absolute configuration of fenfluramine and nor-fenfluramine and suggest that the levo isomer of ortoxine has R-configuration.
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