Biomedical subjects
A Castellucci
Publications and source records attributed to A Castellucci.
[For dental abutments retrograde is better].
Explore the source record for details and available documents.
Effects of 1-[2-ethoxy-2-(3'-pyridyl)ethyl]-4-(2'-methoxyphenyl)piperazine (IP-66), prazosin, yohimbine and dihydroergotoxine mesylate on the vasoconstriction of rat mesenteric artery induced by electric stimulation and exogenous norepinephrine.
The effect of (1-[2-ethoxy-2-(3'-pyridyl)ethyl]-4-(2'-methoxy-phenyl)piperazine (IP-66) on the contraction of rat mesenteric artery induced by electric stimulation (ESV) or by injection of norepinephrine (NESV) was compared with the effects of prazosin, yohimbine and dihydroergotoxine mesylate (DHEM). Interference of propranolol on the effects of the 4 alpha-blockers was also considered. Prazosin has proved to be the strongest antagonist of alpha 1-receptors towards which, however, it showed a certain bond latency. In particular conditions related to increased perfusion time and concentrations prazosin also seemed to lose selectivity towards alpha 1-receptors. It was observed that yohimbine is a weak postsynaptic antagonist whereas DHEM showed scarce selectivity. IP-66 proved to be a strong postsynaptic antagonist with negligible presynaptic effect. It was not as strong as prazosin but its bond with alpha 1-receptors appeared more rapid and steady. Results obtained with prazosin or DHEM and propranolol seemed to suggest an equilibrium between beta 2- and alpha 1-receptors shifted towards the latter.
In vitro comparison of pre- and postsynaptic effects of dihydroergotoxine mesylate and 1-[2-ethoxy-2-(3'-pyridyl)ethyl]-4-(2'-methoxy-phenyl) piperazine (IP-66).
The effects caused on the intestine mesenteric artery preparation by 1-[2-ethoxy-2-(3'-pyridyl)ethyl]-4-(2'-methoxy-phenyl) piperazine (IP-66), a compound having a prevailing alpha-blocking action, and by dihydroergotoxine mesylate (DHEM) were compared in normal conditions and in propranolol-induced beta-receptors block. The two drugs behaved in a completely different way both on vasoconstrictor response (delta p) and on noradrenaline (norepinephrine, NA) outflow induced by electrical stimulation of periarterial nerves. In fact IP-66 inhibited delta p much more than DHEM did but, unlike the latter, it increased NA outflow only at the lowest concentration (8.7 X 10(-9) mol/l) whereas it reduced it at the highest one (2.9 X 10(-7) mol/l). Moreover the effect of IP-6--but not that of DHEM--on NA outflow was completely abolished by propranolol. The hypothesis is put forward that IP-66 may show a strong antagonism towards postsynaptic alpha-receptors and a slight agonism towards presynaptic beta-receptors.
Synthesis of five N-derivatives of 1,2,3,4-tetrahydroisoquinoline and three N alpha terminal histidine peptides as potential gastric histidine decarboxylase inhibitors.
Explore the source record for details and available documents.
The rat mesenteric artery-intestinal loop preparation. Noradrenaline outflow and vascular responses to nerve stimulation and drugs.
A new preparation, intestine-mesenteric blood vessels of the rat, was tested for simultaneous measure of noradrenaline (NA) overflow and vasoconstrictor response (delta p) induced by electric stimulations. Control experiments showed that this preparation could be used within a wide range of frequencies and repeatedly stimulated without any important decrease of response. The effects of phenoxybenzamine, dihydroergotoxine mesylate, imipramine and pargyline were investigated. All the drugs inhibited delta p and, except for dihydroergotoxine mesylate, increased NA outflow. The results were discussed in the light of the present knowledge. It is concluded that this preparation can be profitably used to study drug effects at pre- and post-synaptic level.
Synthesis and pharmacological study of new 1,4-disubstituted piperazines.
Explore the source record for details and available documents.
Lack of hypotensive and brain catecholamine depleting effects by erythro- and threo-alpha-methyl DOPS.
An investigation was carried out to ascertain whether erythro- and threo-alpha-methyl-dihydroxy-phenyl-serine were able of depleting cerebral and peripheral norepinephrine (NE) through their metabolization to alpha-mNE. The results show that the alpha-methyl-aminoacids were decarboxylated only at the periphery and that the threo-form caused depletion in cardiac NE. In any case, both isomers were unable to cross the blood-brain barrier leaving the cerebral NE unaffected. Consequently the use of alpha-mDOPS as alternative tool to alpha-mDOPA in the therapy for hypertension seems unlikely to occur. The results also provide evidence for differences in the pharmacokinetics of the two isomers.
Antilipolytic effect of tiadenol and clofibrate in rat epididymal fat pads.
Explore the source record for details and available documents.
Role of histidine-decarboxylase inhibitors on gastric acid secretion in the rat.
The comparison between DL-alpha-(hydrazino)-beta-4(5)imidazolyl-propionic acid (alpha-HH) and DL-gamma-N(1,2,3,4-tetrahydroisoquinolyl)-alpha-hydrazino-butyric acid (AIS 48), a new inhibitor of histidine-decarboxylase shows that both compounds inhibit enzyme activity in vitro and lower gastric histamine content and acid secretion in vivo. The potency of AIS 48 is of the same order as that of alpha-HH while its toxicity is lower. Although AIS 48 is not a selective histidine-decarboxylase inhibitor, it does not affect tissue cathecholamine levels.
Metabolic effects of bunaftine, a new antiarrhythmic agent: comparison with quinidine, ajmaline, procainamide, xylocaine and propranolol.
The effects of bunaftine (Meregon), quinidine, ajmaline, procainamide, xylocaine and propranolol have been investigated on glycolysis and oxygen consumption of rabbit heart and on the metabolic rate of trained rats. Quinidine, bunaftine and ajmaline stimulated glycolysis, procainamide was inactive while xylocaine and propranolol inhibited it. Myocardial oxygen consumption was reduced by quinidine and bunaftine only at high concentrations. However quinidine at 1-10(5) g/ml showed stimulating effect. Ajmaline and procainamide were inactive; xylocaine had a weak stimulating effect at 1-10(-6), propranolol had a stimulating effect at 3-10(-5) and 1-10(6) while it had an inhibiting effect at 1-10(-4) and 5-10(-3). With the exception of xylocaine and propranolol, which inhibited metabolic rate of trained animals, all the other drugs were inactive. In view of these findings, the mechanism of action of anti-arrhythmic drugs is discussed and it is suggested that the metabolic changes they induce are to be considered as secondary or toxic effects, the main site of action being the myocardial cell membrane.
Correlation of brain catecholamines with cortical acetylcholine outflow, behaviour and electrocorticogram.
Explore the source record for details and available documents.
The changes of gastric histidine decarboxylase activity during fasting and feeding.
Explore the source record for details and available documents.
Harmonized Italian version of the Aging Males' Symptoms scale.
INTRODUCTION: The interest in clinical investigations in health-related quality of life (HRQoL) of aging men has increased over recent years, particularly in the context of partial androgen deficiency. The aim of this paper is to inform the scientific community about a harmonized Italian Aging Males' Symptoms (AMS) scale. METHODS: There were two slightly different Italian AMS scales, which both underwent an up-to-date linguistic & cultural translation process, i.e., were both valid to be applied in clinical research. However, there are potential long-term problems associated with having two Italian language versions of the scale in the same country. Therefore, an ad hoc committee of key persons related to both versions met with the scale's developer, to create a harmonized single Italian AMS. RESULTS: The harmonization meeting came up with a consensus item-by-item and the new Italian reference scale was agreed upon. It was decided that this scale should be published to avoid any confusion among future users. CONCLUSION: The Italian AMS scale published in this paper should be used for future clinical and other research.