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F Venturi

Publications and source records attributed to F Venturi.

At least 19 recordsLinked to original sources
PubMed1998

Application of taste reactivity to study the mechanism of alcohol intake inhibition by the tachykinin aminosenktide.

Tachykinin NK-3 receptor agonists reduce alcohol intake in alcohol-preferring rats; the nucleus basalis magnocellularis (NBM) is highly sensitive to their effect. Tachykinins and their receptors are widely distributed in gustatory pathways and NK-3 receptor agonists have been reported to modify taste reactivity to salt solutions in rats. The present study evaluated whether the TK NK-3 receptor agonist aminosenktide (NH2-SENK) influences taste reactivity to ethanol solutions. Genetically selected Marchigian Sardinian alcohol-preferring (msP) rats were employed. In response to the intraoral infusion (0.8 ml in 1 min) of 10, 20, 40, or even 60% ethanol solution, ethanol-naive rats showed a large number of ingestive reactions and a much lower number of aversive reactions. Two min before the intraoral infusion of 10 or 40% ethanol, NH2-SENK was injected either into the lateral ventricle (LV) or into the NBM. Doses of NH2-SENK that markedly reduce alcohol intake, 125 ng/rat into the LV or 5 ng/site into the NBM, did not modify the ingestive reactions and, in some instances, reduced the aversive reactions to ethanol solutions in ethanol-naive rats. Injections of 125 ng/rat into the LV failed to modify taste reactions in ethanol-experienced rats. The present results show that msP rats have an innate hedonic evaluation of ethanol solutions, even of high concentration. Moreover, they indicate that reduction of ethanol intake induced by TK NK-3 receptor agonists in alcohol-preferring rats does not depend on influences on gustatory processes.

Afferent Pathways↗
PubMed1994

Sex difference in sensitivity to exogenous oxytocin in different models of sodium appetite in the rat.

Brain oxytocin (OT) has been suggested to be involved in the inhibition of sodium appetite in the rat. Sodium depleted male rats showed no decrease in sodium intake after they were given a pulse intracerebroventricular (pICV) injection of either OT (1 microgram/microliter) or the selective OT agonist Tyr4-Gly7OT (1 microgram/microliter). Administration of the OT selective antagonists, d(CH2)5Tyr(Me)-[Orn8]vasotocin and Compound VI [d(CH2)5,Tyr(Me)2,Thr4,Tyr-NH2(9)]OVT (1 microgram/microliter), did not further increase their sodium intake. On the other hand, sodium appetite of sodium depleted female rats were inhibited by the same dose of pICV OT but not by the selective agonist Tyr4-Gly7 OT (1 microgram/microliter). The reduction od sodium appetite in female rats may have been in part due to the competitive behavior of grooming that followed the OT injection. Nevertheless, the OT inhibition in females of the need-free sodium intake and of the sodium appetite that occurs after furosemide but not in adrenalectomized or DOCA treated rats, argue for a mechanism independent from angiotensin or aldosterone alone related sodium appetite and the mechanism involved in the suppression of these salt intakes remain to be clarified.

Adrenalectomy↗
PubMed1993

[The effect of the angiotensin III (Sar1, Ile7) Ang III, on water intake of Wistar rats].

A[Sar1, Ile7] AngIII, an angiotensin III analogue apparently devoid of any affinity for vascular angiotensin II (AngII) receptors, inhibits AngII-induced drinking but neither affects cellular dehydration-induced drinking nor produces any intake of water in water replete rats, suggesting that the dipsogenic effect of AngII is not of vascular origin. Thus, [Sar1, Ile7] AngIII is an interesting tool to study the central effects of AngII.

Angiotensin II↗
PubMed1991

Acute hemodynamic effects of intravenous diperdipine, a new dihydropyridine derivative, in coronary heart disease.

The acute hemodynamic effects of a new dihydropyridine calcium channel blocker, diperdipine, which is suitable for intravenous administration, were studied by right and left cardiac catheterization in 16 patients with coronary heart disease. Diperdipine markedly reduced systemic vascular resistance and improved stroke index and left ventricular ejection fraction. Mean pulmonary artery and wedge pressures were slightly increased as a possible consequence of enhanced venous return, whereas right atrial and left ventricular end-diastolic pressures were not significantly changed. Nevertheless, an increase in preload was clearly indicated by an augmented left ventricular end-diastolic volume index after administration of diperdipine. Left ventricular contractility, which was estimated by the end-systolic pressure-volume ratio and by dP/dt max was not significantly changed, though analysis of individual data suggests a minimally negative inotropic effect. However, such a minor effect on left ventricular contractility was largely counterbalanced by the marked reduction of afterload, which produced a sharp improvement of stroke index. Enhancement of left ventricular ejection fraction and reduction in systemic vascular resistance were inversely and directly correlated to control values. Overall, diperdipine was well tolerated, but one patient had a major untoward reaction that consisted of an ischemic episode that was possibly related to drug administration. In conclusion, intravenous diperdipine appears to be a potent arteriolar dilating agent that does not affect left ventricular contractility.

Calcium Channel Blockers↗
PubMed1989

[Physalaemin-like N-terminal fragments of mammalian tissues, PHLIP-7 and PHLIP-8 do not modify drinking behavior and sodium appetite in rats].

PHLIP-7 and PHLIP-8, two peptides reproducing at least in part the N-terminal aminoacid sequence of physalaemin, have been identified in mammalian tissues. These peptides produce alterations of fighting behaviour in the mouse, but are devoid of any behavioural activity in the rat. This suggests that PHLIP-7 and PHLIP-8 have no affinity for brain receptors involved in the behavioural effects evoked by tachykinins in the rat, and that the brain of this animal is lacking in receptors for the N-terminal sequence of tachykinins.

Amino Acid Sequence↗
PubMed1986

Hypotensive effect in dogs and rats of intravenous injections of the alpha 1-adrenoreceptor antagonist benoxathian.

The hypotensive effect of the alpha 1-adrenoreceptor antagonist benoxathian has been evaluated in rats and dogs, in comparison to that evoked by WB 4101 and prazosin. In anaesthetized dogs, i.v. injection of benoxathian (25-100 micrograms/kg), WB 4101 (5-25 micrograms/kg) and prazosin (50 micrograms/kg) produced an immediate fall in diastolic blood pressure, which reached a maximum at about 30 sec after drug administration. Whereas the hypotensive effect of prazosin persisted up to 3 hr following injection, the effect of both benoxathian and WB 4101 completely disappeared after 30-60 min. The hypotensive effect of benoxathian was dose-dependent. Pressor responses to i.v. noradrenaline (5 micrograms/kg), adrenaline (5 micrograms/kg) and phenylephrine (20 micrograms/kg) were markedly inhibited (60-75%) by benoxathian (100 micrograms/kg) whilst the pressor response to angiotensin II (0.05 micrograms/kg) was not reduced, but indeed slightly increased. The hypotensive effect of benoxathian (100 micrograms/kg) was abolished following pre-treatment with prazosin (50 micrograms/kg) or hexamethonium (1000 micrograms/kg). In anaesthetized rats similar results were obtained although recovery in blood pressure from the initial drop after i.v. injection of the drugs was slower than in dogs. Benoxathian was slightly more toxic than WB 4101 in rats. In conclusion, present findings show that benoxathian causes a profound hypotensive effect in dogs and in rats through postsynaptic alpha-adrenoreceptor blockade; however its effect, as well as that of WB 4101, is shorter lasting than that of prazosin.

Adrenergic alpha-Antagonists↗
PubMed1986

Synthesis and dopaminergic activity of trans-6-methyl-7a,8,9,10,11,11a-hexahydro-7H-pyrrolo[3,2,1-gh]- 4,7-phenanthroline and trans-1,2,3,4,4a,5,6,10b-octahydro-4,7-phenanthroline derivatives.

The synthesis and dopamine agonist activity of some derivatives of trans-6-methyl-7a,8,9,10,11,11a-hexahydro-7H-pyrrolo[3,2,1-gh]- 4,7-phenanthroline (6a-c) are reported. These compounds can be regarded as analogues of ergoline derivatives with the indole nucleus replaced by indolizine. These congeners have been evaluated as inhibitors of prolactin release in vivo. trans-6-Methyl-8-ethyl-7a,8,9,10,11,11a-hexahydro-7H-pyrrolo[3,2,1-gh]- 4,7-phenanthroline (6b) proved to produce a dose-dependent inhibition of serum prolactin that was almost complete at the highest dose employed. Although effective, this compound was far less potent than bromocriptine. The 8-propyl derivative 6c was weakly active only at very high doses, and the 8-methyl derivative 6a proved to be completely ineffective. trans-4-Propyl-1,2,3,4,4a,5,6,10b-octahydro-4,7-phenanthroline (7), a molecular simplification of hexahydropyrrolo-4,7-phenanthroline, proved to be the most potent among the newly synthesized compounds. These results, taken together with those of previous studies, suggest that the presence of the nitrogen of the indolizine nucleus and the N-7 in the octahydro-4,7-phenanthroline 7 are significant for the interaction with the dopamine receptor involved in the control of prolactin release.

Animals↗
PubMed1985

[Synthesis and antiinflammatory activity of various 1,4-benzothiazine derivatives].

A new series of dihydro-4H-1,4-benzothiazine derivatives was prepared. These compounds were obtained by reductive N-alkylation reaction with sodium borohydride in acetic acid of the corresponding 4H-1,4-benzothiazine. Some of the latter compounds were synthesized by a new synthetic method employing 2-aminobenzenethiol and alkynes as starting material. Preliminary pharmacological data on the antiinflammatory activity of these compounds by using carrageenin paw edema assay are reported.

Animals↗
PubMed1980

[Hydrogenated and cyclohomologous derivatives of phenothiazine. Synthesis and pharmacological activity of various cycloalkyl derivatives of 4H-benzo(b)(1,4)thiazine].

The synthesis and the results of pharmacological screening of 4H-benzo[b][1,4]thiazine derivatives are described. These substances were prepared by reacting 2,2'-dithiodianiline with ethyl-2-oxocycloalkanecarboxylates followed by NaBH4 reduction. The pharmacological results indicate remarkable depressive activity [see (IV b) (n = 3)] shown by 100% potentiation of barbituric-induced sleeping time.

Animals↗