PubMed Health⌕ Search

Biomedical subjects

F V DeFeudis

Publications and source records attributed to F V DeFeudis.

At least 55 records · Page 3Linked to original sources
PubMed1982

Inhibition of foot intake in the rat.

The effects of single oral administrations of tricyclic antidepressants (imipramine and desipramine), an atypical antidepressant (nomifensine), known anorexic agents, haloperidol, and diazepam on food intake were compared in Sprague-Dawley rats over a 4-day test period. The tricyclic antidepressants produced decreases in food intake during the total 4-day test period following their administration. In contrast, the anorexic agents (d-amphetamine, cocaine, mazindol, fenfluramine and quipazine), and nomifensine, and haloperidol produced decreases in food intake only on their administration. Diazepam produced an increase in food intake only on the day of its decrease food intake, this model appears to show some specificity for tricyclic antidepressants.

Animals↗
PubMed1982

Further characterization of the anorexic action of orally-administered THIP, a GABA-analogue, in the rat.

Sprague-Dawley rats were used to further characterize the anorexic action of orally-administered THIP, a GABA-analogue. The anorexic action of THIP (5 or 10 mg/kg) was antagonized by prior subcutaneous injection of bicuculline (1 mg/kg), but not by prior subcutaneous injection of bicuculline-methobromide (1.5 mg/kg), strychnine-SO4 (0.75 mg/kg), pentylenetetrazol (25 mg/kg), or picrotoxin (1 mg/kg). Orally-administered GABA (50-300 mg/kg), bicuculline (1-10 mg/kg) or picrotoxin (1-10 mg/kg) generally did not inhibit food intake. These results indicate that the anorexic action of THIP is mediated by central GABA-receptors.

Administration, Oral↗
PubMed1982

A regional difference in the in vitro response of the rabbit vena cava to norepinephrine.

1. Isotonic concentration-response curves were constructed for the contractile effects of norepinephrine (NE) in venous strips prepared from the caudal and rostral portions of rabbit vena cava; in some cases the venous strips were damaged by scraping their inner (endothelial) surface with a scalpel. 2. In both control and damaged venous strips, the rostral portions exhibited a higher affinity and a greater capacity of contraction to applied NE than caudal portions. 3. Such results might be explained by a difference in the distribution (or characteristics) of alpha-adrenoceptors and/or by a difference in the ratio of circular to longitudinal muscular elements in these two regions of the vena cava. 4. These findings should be considered when designing experiments aimed at determining the effects of alpha-adrenoceptor agonists on rabbit vena cava.

Animals↗
PubMed1982

Studies on food intake in the fasted rat.

1. The effects of orally- and intravenously-administered d-amphetamine-SO4, fenfluramine-HCl and cocaine-HCl on food intake in the fasted rat were compared. 2. During the first hour after presentation of food to the animals, ED50 values for suppression of food intake after intravenous injection were: d-amphetamine-SO4, 0.1 mg/kg; fenfluramine-HCl, 0.6 mg/kg; cocaine-HCl, 1.0 mg/kg, ED50 values for suppression of food intake after oral administration were: d-amphetamine-SO4, 0.3 mg/kg; fenfluramine-HCl, 0.7 mg/kg; cocaine-HCl, 9 mg/kg. 3. Over a 4 hr test period, d-amphetamine, fenfluramine and cocaine produced dose-dependent anorexigenic effects only when orally administered. 4. Orally-administered quipazine-maleate and mazindol also decreased food intake, their respective ED50 values being 7 mg/kg and 1.2 mg/kg for the first hour of testing; the anorexigenic effect of mazindol appeared to be more sustained than those of the other anorexigenic agents tested in that it was evident on the day after drug administration. 5. Orally-administered diazepam increased food intake on the day of its administration, but decreased food intake on the day after its administration. 6. In addition to providing further evidence for the effects of several typical anorexigenic agents, the model described might be useful for further studies on anorexigenic agents and minor tranquillizers.

Animals↗
PubMed1982

Actions of D 600 on isolated rabbit aorta.

1. The actions of D 600 (10(-9)-10(-4) M) on various phases of NE- or Ca2+-induced contractions of rabbit isolated aorta were determined in Ca2+-free medium. 2. D 600 inhibited the slow phase of contraction with EC50 approximately equal to 3 X 30(-8) M, but affected the rapid phase of contraction only at 10(-4) M. 3. D 600 increased the relaxation that followed the rapid phase of NE-induced contraction in Ca2+-free medium with EC50 approximately equal to 1.5 X 10(-5) M. 4. The method described might be useful for further studies on Ca2+-antagonists.

Animals↗
PubMed1982

Effects of diltiazem on renovascular-hypertensive and on normotensive rats.

1. The effects of 10-min perfusions of diltiazem (o.1-2.5 mg/kg, i.v.) on arterial blood pressure were studied in anesthetized renovascular-hypertensive and in normotensive rats. 2. Diltiazem produced a dose-dependent decrease in blood pressure in hypertensive rats (ED50 congruent to 1 mg/kg). 3. Diltiazem also decreased blood pressure in normotensive rats, but this action was less sustained than in hypertensive rats. 4. These results support the contention that diltiazem might be useful for treating arterial hypertension.

Animals↗
PubMed1982

Effects of Ginkgo biloba on arterial smooth muscle responses to vasoactive stimuli.

1. An extract of Ginkgo biloba (Gb), at a concentration (100 microgram/ml) that did not provoke isometrically-recorded contractions of rabbit aorta, was tested on the contractile effects of norepinephrine (NE), serotonin (5-HT) and dopamine (DA). 2. Gb potentiated the contractile effect of NE (reduced the EC50 from 75 to 36 nM), but had no obvious action on the contractile effects of 5-HT or DA. 3. These results indicate that low concentrations of Gb might influence catecholaminergic systems by an indirect mechanism.

Animals↗
PubMed1982

Lack of effect of the peptide pyro-Glu-His-Gly-OH on food consumption in mice and rats.

1. Single subcutaneous injections (0.5-10 mg/kg) or repeated oral administration (5 mg/kg, twice daily for 3 or 5 days) of the proposed anorexigenic peptide pyro-GLU-HIS-GLY-OH did not affect food intake in the mouse. 2. Single intravenous injections (0.05-1 mg/kg) or daily intravenous injections (0.3-10 mg/kg, for 5 days) of pyro-GLU-HIS-GLY-OH did not affect food intake in the rat. 3. These results, together with results obtained recently by other workers, indicate that pyro-GLU-HIS-GLY-OH does not have anorexigenic properties in rodents.

Animals↗
PubMed1982

Effects of an extract of Ginkgo biloba on rabbit isolated aorta.

1. Extract of Ginkgo biloba (Gb) provoked a dose-dependent contraction of spirally-cut rabbit aortic strips (EC50 congruent to 1.0 mg/ml) by an action that was antagonized by phentolamine (10(-7) M). 2. Inhibitors of catecholamine re-uptake, cocaine (10(-5) M) and desipramine (10(-7) M) potentiated the contractile effect of norepinephrine (NE), but inhibited the contractile effects of Gb and tyramine. 3. A comparison of the actions of Gb, NE and tyramine using aortic strips prepared from control and reserpine-treated rabbits revealed that reserpine treatment increased the response to NE but decreased the response to Gb and tyramine. 4. The contractile action of Gb on rabbit isolated aorta involves, at least in part, a release of catecholamines from endogenous tissue stores.

Animals↗
PubMed1982

Pharmacological comparison of the potential antidepressant UP 614-04 with viloxazine and imipramine; behavioral studies.

1. Several behavioral tests were used to compare the pharmacological activity of the potential antidepressant UP 614-04 with those of viloxazine and imipramine. 2. Orally-administered UP 614-04, like viloxazine, reduced locomotor activity in mice, and, like viloxazine and imipramine, it antagonized the hypothermia or ptosis induced by reserpine or tetrabenazine and the hypothermia induced by a high dose of apomorphine. 3. UP 614-04 antagonized oxotremorine-induced hypothermia, and to a lesser extent, oxotremorine-induced tremors, indicating that it possesses some CNS anticholinergic activity. 4. Both imipramine and viloxazine were more potent than UP 614-04 in potentiating yohimbine toxicity in mice. 5. Orally-administered UP 614-04 potentiated d-amphetamine-induced stereotypy to a greater extent than viloxazine, but to a lesser extent than imipramine. 6. Intraperitoneally-injected UP 614-04 was much more potent than viloxazine in increasing tryptamine convulsive potential in rats, indicating that it might exert an inhibitory action on monoamine oxidase. 7. These results indicate that UP 614-04 has a behavioral profile that is consistent with an antidepressant action, but that it differs from imipramine and viloxazine.

Animals↗
PubMed1982

Effect of an extract of Ginkgo biloba on the isolated ileum of the guinea-pig.

1. The effects of an extract of Ginkgo biloba (Gb) were studied using the guinea-pig isolated ileum. 2. Using isometric recording, the dose-response relation for the action of Gb was complex, and at 400 micrograms/ml was reproducibly biphasic--a relaxation followed by a contraction. 3. Droperidol (3 X 10(-7) M - 10(-6) M), cyproheptadine (10(-7) M), and diphenhydramine (10(-7) M) prolonged the relaxation and usually decreased the amplitude of the contraction produced by Gb (400 micrograms/ml), whereas phentolamine, hexamethonium, methysergide, or cimetidine (10(-7) or 10(-6) M) did not affect the response to Gb. 4. The action of Gb on the guinea-pig ileum might involve mechanisms associated with dopamine and/or histamine.

Animals↗
PubMed1982

A comparison of the dose-response effects of captopril in anesthetized normotensive and renovascular hypertensive rats.

1. Dose-response effects of captopril in an acute model of renovascular hypertension in the anaesthetized rat and in normotensive anaesthetized rats were compared. 2. Intravenous infusions of captopril lowered the blood pressure of both hypertensive and normotensive rats, its minimal active dose being about 0.05 mg/kg. 3. The 0.1 mg/kg dose of captopril normalized the blood pressure of hypertensive rats. 4. The model described herein might be useful for screening inhibitors of the angiotensin-converting enzyme.

Animals↗