Biomedical subjects

F Ferrari

Publications and source records attributed to F Ferrari.

At least 127 records · Page 7Linked to original sources

PubMed1993

Behavioural effects induced in rats and chicks by D2 dopamine agonists.

In a first series of experiments, different selective dopamine D2 receptor agonists (B-HT 920, B-HT 958, SND 919, CQ 32-084, CQP 201-403, and lisuride) and the D1/D2 agonist apomorphine were IP injected into adult male rats. At low doses, they elicited repeated episodes of penile erection and stretching-yawning: at all doses tested, B-HT 920, B-HT 958, and CQ 32-084 also induced hypomotility, a sign that, in the case of high doses of SND 919, CQP 201-403, lisuride, and apomorphine, was replaced by stereotyped behaviour. In a second series of experiments, the same D2 agonists and the mixed D1/D2 agonist apomorphine were IP injected at the same doses into chicks. The following behavioural signs were observed: hypomotility, sleep-like state, and stereotyped pecking. The results show that: 1. there are similarities between the behavioural effects induced by the DA agonists in rats and chicks; and 2. in both species some behavioural signs elicited by the DA ergic compounds are useful pointers to their specific neurochemical activity.

Animals↗

PubMed1993

Behavioural profile in the chicken of CQ 32-084 and CQP 201-403, two dopamine agonists.

CQ 32-084 and CQP 201-403, two ergot derivatives that previous behavioural studies in rats had suggested to be differently active on dopamine (DA) receptors, were IP injected into male chickens. Both compounds strongly modified the animals' behaviour. CQ 32-084 led to sedation, increased yawning, and decreased preening, while CQP 201-403 exerted a biphasic activity: At a low dose, it elicited sedation and yawning; at high doses, however, it induced a state of excitation manifested by diminished sedation and yawning, enhanced preening, and pecking. The sedation, increased yawning, and decreased preening induced by the two DA agonists were reversed by the D2-selective antagonist, sulpiride. The present studies indicate that, from a behavioural point of view, chickens respond similarly to rats to the DA agonists CQ 32-084 and CQP 201-403, which differ in their selectivity of action on the various DA receptor subtypes.

Animals↗

PubMed1993

Pharmacological analysis of the methanolic extract and sorocein A, a new Diels-Alder compound isolated from the roots of Sorocea bonplandii Bailon in the isolated rat uterus and guinea pig ileum.

1. This study examines the effects of methanolic extract (ME) and its main constituent, sorocein A, isolated from the roots of Sorocea bonplandii on agonist-induced contractions in the rat uterus (RU) and in the guinea pig ileum (GPI) in vitro. 2. ME (25-100 micrograms/ml), added to RU for 20 min, caused a graded and parallel shift to the right of bradykinin (BK)-mediated contractions with an apparent pA2 value (-log g/ml) of 5.0 ME caused a rightward shift of the acetylcholine (ACh) and oxytocin-induced contractions associated with a marked depression of their maximal responses. 3. In GPI, ME produced a non-competitive antagonism against BK-induced contraction, while responses to ACh and histamine were shifted to the right in a graded fashion, yielding pA2 values (g/ml) of 5 in both cases. 4. The purified compound sorocein A (15-60 microM) caused a parallel and graded rightward displacement of BK and ACh concentration-response curves in RU with pA2 values (molar basis) of 4.9 and 5.2. 5. Sorocein A also dose-dependently shifted to the right ACh and histamine-mediated contractions in GPI, yielding pA2 values of 5.1 and 4.8, respectively. 6. However, sorocein A antagonized in a non-competitive manner BK-induced contraction in GPI, characterized by a graded displacement to the right of the dose-response curve, and progressive depression of the maximal contraction.

Acetylcholine↗

PubMed1993

Prevalence of glomerular hyperfiltration and nephromegaly in normo- and microalbuminuric type 2 diabetic patients.

Glomerular hyperfiltration, correlated with nephromegaly, is a frequent finding in type 1 (insulin-dependent) diabetes. In type 2 (non-insulin-dependent) diabetes, very few studies have been performed, and the results have been inconclusive. Glomerular filtration rate (GFR) and kidney volume, using 99mTc-DTPA scintigraphy and ultrasonography, respectively, were evaluated in 58 control subjects and 163 type 2 diabetic patients; 79 of whom were normoalbuminuric and 84 microalbuminuric. In the two groups of patients, these parameters did not differ significantly from those of controls, even when hypertensive subjects were excluded. Glomerular hyperfiltration was observed in 10 cases; all were normotensive (9.8%), of whom 7 were normoalbuminuric and 3 microalbuminuric. Nephromegaly was observed in 3 other normotensive microalbuminuric diabetic patients. Hypertensive subjects showed a lower GFR than normotensive patients and control subjects. Multivariate analysis showed a negative correlation between glomerular filtrate and systolic blood pressure (BP) in the overall population of patients and in normo- and microalbuminuric patients taken separately. It is concluded that the relationship between these variables forms a continuum in our type 2 diabetic patients; it may also be important in determining the low prevalence of hyperfiltration and nephromegaly found in our patients, who had BP levels higher than those of controls.

Adult↗

PubMed1993

[Objective prevention of ictus. Data informatics from a mass screening program].

The main technical and functional abilities of the computer supply to the epidemiologic program Obiettivo Prevenzione Ictus are described. The aim of the program is to investigate the epidemiology of carotid occlusive disease in subjects aged 45 to 75 by following a diagnostic and therapeutic protocol, designed to discover and treat internal carotid artery stenosis. The magnitude of the population involved is 23,140 subjects. The data from the population are collected in a three level archive whose configuration makes it possible to obtain information either from within each level and from all of them. Thus, the software adopted provides specific tools for elaboration of epidemiologic data as well as for clinical management of carriers of carotid lesion and for follow-up of treated patients.

Aged↗

PubMed1992

CR 2039, a new bis-(1H-tetrazol-5-yl)phenylbenzamide derivative with potential for the topical treatment of asthma.

The pharmacological activity of CR 2039 (4-(1H-tetrazol-5-yl)-N-(4-[1H-tetrazol-5-yl]phenylbenzam ide)) a newly discovered antiallergic compound is described. CR 2039 administered i.m. or i.v. inhibited rat passive cutaneous anaphylaxis (PCA) with an ED50 of 0.1 mg/kg and a potency about 15 times higher than that of disodium cromoglycate (DSCG). CR 2039 i.m., by aerosol or as dry powder insufflation, gave dose-related significant protection against IgE-dependent bronchial anaphylaxis induced by aerosolized antigen in anesthetized guinea-pigs. In conscious guinea-pigs CR 2039 given i.m. delayed dose dependently (ED50, 17 mg/kg) the onset of bronchoconstriction induced by aerosolized antigen, while DSCG was ineffective up to 100 mg/kg. The protection was accompanied by significant inhibition of the vascular permeability provoked by antigen challenge in all airway segments except trachea. CR 2039 (10-100 mg/kg i.v.) inhibited the microvascular permeability changes in a model of allergic conjunctivitis in sensitized guinea-pigs. CR 2039 inhibited dose dependently guinea-pig lung cAMP-phosphodiesterase with an IC50 of 50 microM.

3',5'-Cyclic-AMP Phosphodiesterases↗

PubMed1992

Suppressive effect of the dopamine D2 receptor agonist B-HT 920 on rat grooming.

The effect of the D2 agonist B-HT 920 was examined on three behavioural models of induced grooming in the rat. B-HT 920 potently inhibited the grooming elicited by a novel environment, whereas it stimulated the stretching-yawning syndrome. Pretreatment with the selective dopamine D2 receptor antagonist, sulpiride, reversed the phenomenon. When B-HT 920 was administered to rats before water immersion, it similarly antagonized total grooming; wet-dog shakes, detected in these same animals, were potently inhibited. Finally, B-HT 920 displayed inhibitory activity towards adrenocorticotropin hormone-induced excessive grooming. On the basis of these effects, the role of D2 receptor subtypes in the modulation of grooming is discussed.

Analysis of Variance↗

PubMed1992

Characterization of antigastrin activity in vivo of CR 2194, a new R-4-benzamido-5-oxo-pentanoic acid derivative.

The antigastrinic activity, in vivo, of CR 2194 (R-4-(3-chlorobenzamido)-5-(8-azaspiro[4.5]decan-8-yl) -5-oxo pentanoic acid) was assessed in various animal species. CR 2194 antagonized pentagastrin-stimulated gastric acid secretion in the rat (ID50 = 11 mg/kg i.v.), dog (ID50 = 5.9 mk/kg i.v. or 28.8 mg/kg os) and cat (ID50 = 15.5 mg/kg i.v.). CR 2194, in the cat, inhibited both competitively and non-competitively the gastric acid secretion stimulated with increased doses of pentagastrin, with a pA2 of 4.89. In the rat and in the dog the antagonism seemed to be non-competitive and the respective pD'2 calculated were 4.54 and 4.42. The interaction of CR 2194 with the gastrin receptors appeared reversible, as demonstrated by the return to normal values of the acid output after the conclusion of the i.v. infusion, during pentagastrin continuous stimulation in the dog. The antigastrin activity was specific: CR 2194 was unable to antagonize the gastric acid secretion stimulated by carbachol or histamine in the rat up to the dose of 100 mg/kg. CR 2194 was effective to antagonize the gastric acid secretion stimulated by gastrin release after meal ingestion in the Heidenhain pouch dog model. The ID50 calculated was 2.89 mg/kg after oral administration. All these characteristics make CR 2194 an important compound in the investigation of the biological effects of gastrin and a potential agent for diagnostic or therapeutic use.

Animals↗

PubMed1992

B-HT 920 stimulates feeding and antagonizes anorexia induced by ACTH and immobilisation.

The influence of immobilisation and i.c.v. injection of ACTH on feeding in rats was examined using a new experimental model. An X-maze with alternate open and covered arms, each baited with standard laboratory chow was used, where individual rats were placed and observed for 5 min. Two essential aspects of the behaviour towards food were considered, namely, tasting and feeding. A number of parameters were applied to demonstrate the anorectic activity of ACTH and immobilisation, in accordance with data obtained using classical procedures for feeding analysis. ACTH at the dose used did not modify rat exploratory activity and grooming in the X-maze without food pellets. In the same X-maze feeding test, B-HT 920, a selective agonist of dopamine D2 receptors and alpha 2-adrenoceptors, shown earlier to have anxiolytic- and antidepressive-like properties in rats, enhanced appetite and exerted anxiolytic activity when injected i.p. Pretreatment with B-HT 920 counteracted the restraint- and ACTH-induced effects. The results are discussed in the light of the relation between control of feeding and affective disorders. B-HT 920 activity seems to be of particular interest in view of its antagonism towards the anorexia elicited by two different agents reputed to have in common a key role in the stress-related disturbances of food intake.

Adrenergic alpha-Agonists↗

PubMed1992

Ornithine decarboxylase and ornithine decarboxylase-inhibiting activity in rat thymocytes.

Isolation of thymocytes from rat thymus resulted in the disappearance of the high activity of ornithine decarboxylase (ODC) that characterizes the thymus of young rats, together with the appearance of an antizyme-like ODC inhibiting activity, which showed a chromatographic profile that resembled that of dexamethasone-treated rat thymus. Omission of serum or addition of dexamethasone or spermidine did not affect appreciably the extent of the antizyme-like activity. On the other hand, a variety of hormonal effectors, i.e. insulin, glucagon, adrenalin and T3, as well as the phorbol ester, PMA or the mitogen, concanavalin A (Con A) induced ODC activity in cultured thymocytes together with the disappearance of the antizyme-like activity. A paradoxical, transient induction of ODC was caused by the transcriptional inhibitor, actinomycin D. Complexed ODC was detected in rat thymus, but not in thymocytes, either quiescent or stimulated by mitogens. These results indicate that thymic lymphocytes can express either ODC activity or its inhibitor depending on the hormonal and proliferative status of the cells.

Animals↗

PubMed1992

Effect of the D2-autoreceptor agonist B-HT 958 on both spontaneous and ACTH-induced stretching, yawning and grooming in the rat.

The D2 autoreceptor agonist B-HT 958, intraperitoneally injected into Wistar male rats in a novel environment, significantly increased stretching and yawning (SY) while inhibiting grooming. Pretreatment with the D2 antagonist sulpiride reversed these effects, antagonizing SY and restoring grooming. Similarly, when B-HT 958 was administered to rats in their home cages, it elicited SY and abolished grooming; moreover, when administered before the i.c.v. injection of adrenocorticotropin hormone, dose-dependently enhanced SY and strongly antagonized the typical syndrome of intensified grooming induced by the peptide. The possible relationship between SY and grooming and the involvement of D2 autoreceptors are discussed.

Adrenergic alpha-Agonists↗

PubMed1992

Effects of the dopamine D2 agonists lisuride and CQ 32-084 on rat feeding behaviour.

The influence on rat-feeding behaviour of lisuride and CQ 32-084, agonists at dopamine D2 receptors, was examined using two procedures. In a first series of experiments, the apparatus was an X-maze baited with food pellets where individual fasted rats were observed for 5 min. A number of parameters were recorded: latency to tasting and feeding, interval between tasting and feeding, total feeding time, and total grooming time. Lisuride (0.05 and 0.1 mg/kg) and CQ 32-084 (0.05 and 0.5 mg/kg) behaved as stimulants of eating; lisuride (0.4 mg/kg) inhibited the phenomenon. Both drugs always antagonized grooming. Subsequently, when food intake was determined in the home cages of fasted animals lisuride reduced feeding at all doses during the first hour after treatment, while CQ 32-084 had no effect. The data show that the two compounds display different activity on ingestive behaviour according to the dose and experimental model used. Discussion centres on the possible dependence of feeding enhancement in the X-maze on the anxiolytic activity exerted by low D2 autoreceptorial doses.

Animals↗

PubMed1992

Bioelectric brain maturation in fullterm infants and in healthy and pathological preterm infants at term post-menstrual age.

At the same post-menstrual age (39-41 weeks), EEG maturation assessed according to the Nolte and Haas method (Nolte, R. and Haas, H.G. (1978) Dev. Med. Child Neurol., 20, 167-182) was studied in 16 fullterm infants (FT), 17 healthy preterm infants (HP) and 18 pathological preterm infants (PP) affected by brain lesions (haemorrhage and/or leucomalacia). There were no significant differences in respect to EEG maturational codes, EEG types or bioelectrical age between the FT and HP groups. The preterm infants affected by brain lesions presented higher percentages of younger EEG codes (i.e. 36 weeks) in State 1 and a higher number of fluctuations between one maturation code and another in both State 1 and State 2, with respect to the HP group. Also, although the PP infants with young EEG codes did not present serious background EEG abnormalities, they did reveal minor EEG abnormalities, such as excessive asynchrony of the 'tracé alternant', lack of frontal sharp transients and monomorphic TA 'bouffees' with little activity at 2-6 c/s. However, no relationship between young EEG codes and onset-offset or duration of the states was found: young codes were often randomly distributed in successive State 1-State 2 epochs, regardless of groupings. Bioelectric age appropriate to the post-menstrual age precedes a normal development or only minor handicap at 24 months, while EEG immaturity of more than 2 weeks corresponds to later major handicaps. The prognostic value of EEG immaturity of between 1.1 and 2 weeks is uncertain.

Brain↗

PubMed1992

[Clinical and prognostic significance of echocardiographic parameters in dilated cardiomyopathy: a prospective study on 225 patients. The Italian Multicenter Study of Cardiomyopathies Group].

To assess the prognostic role of echocardiographic indexes and their relation to clinical conditions, 225 patients with dilated cardiomyopathy were studied prospectively. All cases had a normal coronary angiogram and non specific endomyocardial biopsy findings. 163 men (72.4%) and 62 women (27.6%), mean age 41.5 +/- 12.3 (range 8-61), were studied. Clinical, electrocardiographic and echocardiographic parameters, normalized for body surface area, were tested according to NYHA class and presence of segmental or diffuse wall motion abnormalities. One hundred-four patients were in NYHA class I-IIa, 94 were in class IIb-III and 27 were in class IV. Left ventricular end systolic diameter index, right ventricular end diastolic diameter index, left atrial diameter index, left ventricular fractional shortening and ejection fraction, and radius to wall thickness ratio were significantly more impaired in patients with more severe symptoms. Twenty-eight patients (13%) showed segmental wall motion abnormalities and had smaller left ventricular end systolic and left atrial diameter index and higher left ventricular fractional shortening and ejection fraction. During a mean follow up of 23 +/- 15 months (range 1-67 months), 25 patients (11.1%) died from cardiac causes and 16 (7.1%) underwent heart transplant because of refractory heart failure. Prognostic evaluation was performed separately for cardiovascular mortality alone and for cardiac events (cardiovascular mortality and heart transplantation). At Cox multivariate analysis only right ventricular end diastolic diameter index (p < 0.005) predicted cardiovascular mortality, while left atrial diameter index (p < 0.001), right ventricular end diastolic diameter index (p < 0.01) and left ventricular ejection fraction (p < 0.05) were significant independent predictors of cardiac events.

Adolescent↗

PubMed1992

Induction of ornithine decarboxylase by transcriptional inhibitors in quiescent thymocytes.

The transcriptional inhibitors actinomycin D and dichlororibofuranosylbenzimidazole induced ornithine decarboxylase activity in isolated, quiescent thymocytes, which otherwise did not show detectable levels of the enzyme. This paradoxical induction was transient and dependent on the presence of serum and continuous protein synthesis. However, alpha-amanitin, another inhibitor of transcription, did not affect ornithine decarboxylase activity. Dichlororibofuranosylbenzimidazole and actinomycin D were unable to enhance the activity of spermidine acetyltransferase or S-adenosyl-methionine decarboxylase, which are other inducible and short-lived enzymes involved in the metabolism of polyamines.

Animals↗

PubMed1991

An anthraquinone and three naphthopyrone derivatives from Cassia pudibunda.

Chemical examination of the methanolic extract of the roots of Cassia pudibunda led to isolation of the new rubrofusarin-6-O-beta-D-glucopyranoside, quinquangulin-6-O-beta- D-apiofuranosyl-(1----6)-O-beta-D-glucopyranoside, quinquangulin-6-O-beta-D-glucopyranoside and chrysophanol dimethyl ether. Moreover the known chrysophanol, physcion, cis-3,3',5,5'-tetrahydroxy-4-methoxystilbene, trans-3,3',5,5' -tetrahydroxy-4-methoxystilbene, and cassiaside B were identified. The antimicrobial activity of some of these compounds is also reported.

Anthraquinones↗

PubMed1991

Behavioural evidence for central D-2 dopamine receptor agonistic effect by some 2-(fluorohydroxyphenyl)ethylamines.

The IP injection of 2-(4-fluoro-3-hydroxyphenyl)ethylamines. (FDA 24), N-n-propyl-N-(2-phenylethyl)-2-(3-fluoro-4-hydroxyphenyl)ethylamine (FDA 27F) and N-n-propyl-N-(2-phenylethyl)-2-(4-fluoro-3-hydroxyphenyl) ethylamine (FDA 40) into adult male rats induced the stretching and yawning (SY) syndrome, FDA 24 being the least active. Moreover, FDA 27F and FDA 40 potentiated penile erection (PE) with respect to controls. For both signs (PE and SY), FDA 40 was the most potent of the three compounds. These effects, which are considered typical signs of central D-2-dopamine (DA) receptor stimulation, were dose-related and significantly inhibited by pretreatment with the selective D-2 DA antagonist, sulpiride, but not by domperidone, which does not cross the hematoencephalic barrier. In previous binding studies, FDA 27F and FDA 40 showed high affinity and selectivity for D-2 DA receptors, while FDA 24 had a low affinity for both D-1 and D-2 DA receptors. The present data show that FDA 27F and FDA 40 cross the blood-brain barrier and exert an agonistic effect on the central D-2 DA receptors. These results also provide evidence of the value of PE and SY tests as sensitive tools for the study of DA-neurochemical mechanisms.

Animals↗

PubMed1991

Effects of B-HT 920 in the tail-suspension test.

The effect of B-HT 920 on mice subjected to the tail-suspension test (TST), a behavioural tool for gauging depression, was studied. During the test, all the animals had bouts of agitation interspersed with periods of immobility but B-HT 920-treated animals exhibited a differentiated behavioural pattern according to the dose employed: at doses selective for dopaminergic (DA) autoreceptor stimulation (50 and 100 micrograms/kg), the periods of immobility were unaffected, while at higher doses (0.5, 1, 2 and 3 mg/kg), which are also considered to be active on alpha 2-adrenoceptors, they were much shorter, as they are when known antidepressants are administered. Both clonidine (75 and 150 micrograms/kg) and yohimbine (1 and 5 mg/kg), alpha 2-adrenoceptor agonist and antagonist, respectively, increased immobility time, while N-n-propylnorapomorphine, a DA-agonist, at a dose (10 micrograms/kg) specific for DA autoreceptors, was completely ineffective. Since the behavioural effects of B-HT 920 vary according to the dosage employed, discussion centres on what receptors might conceivably underly these effects and on their preclinical relevance.

Adrenergic alpha-Agonists↗