Showing papers by "University of Cagliari published in 1974"
TL;DR: Rats were trained for 20 days to eat their normal daily meal in a period of 2 hours and on the twentyfirst day they received a diet in which tryptophan was omitted instead of the usual balanced diet, which produced a marked depletion of free serum tryPTophan, brain tryptophile, brain 5-HT and brain5-HIAA.
267 citations
TL;DR: Test the effect of the intragastric administration of different amino acid mixtures not containing Try, on brain Try level and serotonin metabolism and results show that certain amino acid combinations produce a dramatic fall in Try, serotonin and 5-h ydroxyindoleacetic acid in brain and in free and total Try in serum.
Abstract: TRYPTOPHAN (Try) is the only amino acid circulating in plasma which is bound to serum proteins (MCMENAMY & ONCLEY, 1958). Previous studies from our (TAGLIAMONTE et al., 1971a; GESSA et al., 1972; TAGLIAMONTE et al., 1973a; 1973b) and Curzon's laboratories (KNOTT & CURZON, 1972) have shown that the concentration of free Try in serum parallels in many instances the concentration of Try in brain which, in turn, parallels the synthesis rate of brain serotonin (TAGLIAMONTE et al., 1971~; TAGLIAMONTE, et al., 1971b). On the other hand, studies on transport of amino acids from blood to brain on uptake of amino acids by brain slices GUROFF & UDENFRIEND, 1962; OLDENWRF, 1971; &HEN & LAJTHA, 1972) or synaptosomes (GRAHAME-SMITH & PARFITT, 1970) have shown that many of the aromatic acids share the same transport mechanism from blood to brain and that a high concentration of one can lower the uptake or transport of others. These considerations suggest that Try concentration in brain may depend not only on the concentration of free serumTry but also, as suggested by FERNSTROM & WURTMAN (1971), on the plasma concentration of the other amino acids competing for the same transport mechanism. In order to test this hypothesis, we studied the effect of the intragastric administration of different amino acid mixtures not containing Try, on brain Try level and serotonin metabolism. Results show that certain amino acid combinations produce a dramatic fall in Try, serotonin and 5-h ydroxyindoleacetic acid in brain and in free and total Try in serum. MATERIALS AND METHODS
195 citations
TL;DR: The role of brain monoamines in male sexual behavior is described and inhibition of heterosexual copulatory behavior has been observed after the administration of LSD which is considered a direct stimulant of central serotonin receptors.
164 citations
TL;DR: Apomorphine and a combination of Ro 4-4602 with L-DOPA increase the copulatory behavior of male adult rats with a low basal level of sexual activity and this effect is prevented by haloperidol.
Abstract: Apomorphine and a combination of Ro 4-4602 with L-DOPA increase the copulatory behavior of male adult rats with a low basal level of sexual activity. This effect is prevented by haloperidol. This drug also suppresses the spontaneous copulatory behavior in rats with high basal level of sexual activity.
101 citations
TL;DR: Hyperinsulinemia, secondary to peripheral insulin-resistance is normalized by biguanides that are capable of abolishing the signal for hypersecretion, a factor that varies from species to species.
Abstract: Publisher Summary This chapter discusses inhibition of fatty acid oxidation by biguanides and describes its implications for metabolic physiopathology. Biguanides exert their metabolic effects through a single basic mechanism, namely, inhibition of fatty acid oxidation. This mechanism has no connection with the inhibition of oxidative phosphorylation that is rather a toxic effect produced by concentrations too high with respect to the sensitivity of the treated animal, a factor that varies from species to species. Biguanides increase glucose utilization through the Embden–Meyerhof–Krebs pathway, with consequent increase both in the activity of the Cori cycle and in CO2 production from glucose. Biguanides do not inhibit gluconeogenesis indiscriminately; by depressing fatty acid oxidation they exert an inhibitory effect only when pyruvate carboxylase, activated by acetyl-CoA, is the rate-limiting step of gluconeogenesis. Glucose uptake and oxidation in muscle, hindered by increased fatty acid oxidation, are stimulated by biguanides. Hyperinsulinemia, secondary to peripheral insulin-resistance is normalized by biguanides that are capable of abolishing the signal for hypersecretion.
41 citations
TL;DR: Acinar cells of human major salivary glands, fixed and processed for electron microscopy under identical conditions, exhibit secretory granules endowed with distinctive ultrastructural features.
Abstract: Acinar cells of human major salivary glands, fixed and processed for electron microscopy under identical conditions, exhibit secretory granules endowed with distinctive ultrastructural features.
31 citations
TL;DR: In this paper, the preparations of complexes of the type ML2X2, (M = Cu(II), X = Cl, Br, N03, CIO4 Bφ4: M = Ni(II, X = Br, NO3, I, No3, N-Propylimidazole, Npropylimide, No.
29 citations
TL;DR: In this paper, the spectral and magnetic properties of the complexes of copper, nickel, cobalt, and cadmium with isoxazole have been investigated, and they have distorted octahedral structures, whereas some, viz. [Cu isox Cl 2 ] and [Co isox Br 2 ] are tetrahedral.
29 citations
TL;DR: The administration of amphetamine and scopolamine discloses therefore a specific functional impairment of the cerebral cholinergic mechanisms in rats with limbic lesions in rats under urethane anaesthesia.
Abstract: The effect of electrocoagulative lesions placed in the septum, fornix and fimbria, fimbria and hippocampus on ACh release from the cerebral cortex was investigated in rats under urethane anaesthesia. At least 2 weeks elapsed between the stereotactic placement of the lesions and the determination of ACh output. ACh was determined by bioassay on the dorsal muscle of the leech. No lesion affected the spontaneous release of ACh. The increase in ACh output induced by i.p. administration of amphetamine was abolished by the septal lesion only. On the other hand, the increase in ACh output induced by i.p. administration of scopolamine was strongly reduced by lesions of the septum, of the fornix and fimbria and to a lesser extent of the fimbria. The administration of amphetamine and scopolamine discloses therefore a specific functional impairment of the cerebral cholinergic mechanisms in rats with limbic lesions.
26 citations
TL;DR: La synthèse de la somatomammotrophine (HCS) and d'un facteur présentant une réaction immunologique croisée avec l'ACTH a été démontrée dans des cultures de fragments de placenta et de membrane amniotique.
Abstract: La synthese de la somatomammotrophine (HCS) et d'un facteur presentant une reaction immunologique croisee avec l'ACTH a ete demontree dans des cultures de fragments de placenta et de membrane amniotique. Ce facteur est comparable a la corticotrophine chorionique humaine precedemment decrite dans le plasma de femme enceinte et les extraits placentaires.
24 citations
TL;DR: Results indicate that A inhibits DA deamination by monoamine oxidase, and decreases the L‐DOPA‐induced accumulation of HVA and DOPAC in the rat basal ganglia.
Abstract: — Apomorphine (A) inhibited dopamine deamination by rat brain mitochondria, but did not influence catechol-O-methyltransferase (COMT) activity by brain homogenates. The administration of apomorphine (10mg/kg i.p.) to normal rats increased brain dopamine (DA) by 34 per cent and decreased homovanillic acid (HVA) and dihydroxyphenylacetic acid (DOPAC) by 60 per cent. In rats treated with reserpine 15 min prior to A, the latter prevented the rise of cerebral HVA and DOPAC and the depletion of DA produced by the former. Finally, A decreased the L-DOPA-induced accumulation of HVA and DOPAC in the rat basal ganglia. These results indicate that A inhibits DA deamination by monoamine oxidase.
This inhibition seems to be specific since apomorphine did not influence 5-HIAA levels in normal rats and prevented neither central 5-HT depletion nor 5-HIAA rise induced by reserpine.
TL;DR: L'apomorfina e l'associazione dil-DOPA con Ro 4-4602, un inibitore della decarbossilasi non cerebrale, stimolano il comportamento copulatorio nei ratti maschi con scarsa attività sessuale di base.
Abstract: L'apomorfina e l'associazione dil-DOPA con Ro 4-4602, un inibitore della decarbossilasi non cerebrale, stimolano il comportamento copulatorio nei ratti maschi con scarsa attivita sessuale di base. L'effetto afrodisiaco dellal-DOPA e dell'apomorfina e prevenuto dall'aloperidolo.
TL;DR: The present results suggest that in humans, brain serotonin synthesis is greater at midnight that at noon.
TL;DR: Using thiomorpholin-3-one (tm) as ligand, the complexes [M(CO)5tm] (where M = Cr, Mo, W) were prepared.
TL;DR: In this paper, the 1:1 and 1:2 complexes of thiazolidine-2-selenone and thiazolisone with zinc(II), cadmium-(II) and mercury(II) halides have been characterized by molecular conductance and spectral measurements.
TL;DR: Using thiomorpholin-3-thione (ts) as ligand the complexes M(CO)5ts (where M = Cr, Mo, W), which are yellow, crystalline, non-electrolyte and diamagnetic, were obtained as discussed by the authors.
TL;DR: In this article, the electronic absorption spectra of the benzeneseleninate anion were studied and values of the spectral parameters were determined, and it was shown that the complexes are seleninato O, O ′ with the ligand bidentate with a distorted octahedral D 4 h symmetry.
TL;DR: Nella corteccia di uomo la dopamina (DA) è presente in concentrazioni quattro volte maggiori della noradrenalina (NA) e nella scimmia, nel gatto e nel ratto il rapporto DA/NA è rispettivamente di 1.5∶1.
Abstract: Nella corteccia di uomo la dopamina (DA) e presente in concentrazioni quattro volte maggiori della noradrenalina (NA). Nella scimmia, nel gatto e nel ratto il rapporto DA/NA e rispettivamente di 1.5∶1, 2∶1 e 1∶1. Nel ratto la DA corticale e depletata dalla reserpina.
TL;DR: Differential DNA synthesis is demonstrated in asynaptic regions of the polytenic chromosomes of the Anopheles atroparvus x A. labranchiae hybrid and appears to be related to a specific portion of the replication cycle.
Abstract: Differential DNA synthesis is demonstrated in asynaptic regions of the polytenic chromosomes of the Anopheles atroparvus x A. labranchiae hybrid. This differential synthesis is present both in homologous segments with different banding patterns and in morphologically identical segments. Each differential synthesis appears to be related to a specific portion of the replication cycle and due to the fact that one of the two homologues requires a shorter period of time for its duplication.
TL;DR: It is demonstrated that biguanides produce their effects on glucose metabolism through depression of fatty acid oxidation in rat diaphragm homogenate through the inhibition of glucose-U- 14 C oxidation by unlabelled palmitic acid.
TL;DR: The administration of testosterone restored the copulatory behaviour in the castrated rats indicating that testosterone is essential for this behaviour.
Abstract: 1 The effect of p-chlorophenylalanine (PCPA) on the copulatory behaviour of normal and castrated male rats with females in oestrus was studied.
2 Castration 2 months before the experiment completely prevented the increased copulatory behaviour produced by PCPA in normal rats.
3 The administration of testosterone restored the copulatory behaviour in the castrated rats indicating that testosterone is essential for this behaviour.
TL;DR: The present research has confirmed the geographic distribution of these diseases and confirmed that the highest frequencies for all three hemopathies may be observed in the same villages, stressing, despite a few exception^,^.
Abstract: 8-Thalassemia, icterohemoglobinuric favism, * and glucose-6-phosphate dehydrogenase (Gd-PD) deficiency have a very similar distribution in Sardinia.1-2 It was also demonstrated that the incidence of G-6-PD deficiency is practically analogous to that of /3-thalassemia.1-s Studies of the geographic distribution of these diseases show that their frequencies are higher in the low-lying coastal, previously malaria infested areas (15% ), and rather less in the hilly central zones of the island (4% ). The presence of malarial endemism in Sardinia (this disease was wiped out only during the last 15 years) seems to be an important factor, even if not the only one, responsible for the maintenance of a high frequency of these forms.*-5 The present research, which was carried out on 10,099 patients and on 3,045 cases of icterohemoglobinuric favism from different Sardinian areas, has confirmed the geographic distribution mentioned above, stressing, despite a few exception^,^. that the highest frequencies for all three hemopathies may be observed in the same villages (FIGURE 1 , TABLE 1 ) . In spite of the high incidence (12.61 % ) of G-6-PD deficiency in Sardinia, the number of hemolytic crises caused by drugs and especially by favism is certainly not in proportion to the number of Gd-PD-deficient subjects. This fact has been a matter of discussion since the discovery of the relationship existing between drug-induced hemolysis and G-6-PD deficiency, and later when the correlation between this deficiency and favism was established. With this background it seemed opportune to evaluate if and in what measure the presence of both hemopathies in the same individual produce interaction phenomena.
TL;DR: D-amphetamine, which has been shown to increase DA turnover did not increase brain HVA, but significantly increased 5-HIAA in the rat brain, while L-methadone significantly increased brain H VA, but did not influence 5- HIAA levels in rats.
TL;DR: In this article, the thermoluminescent emissions of AgCl and AgBr were investigated as excited at liquid N 2 temperature with UV light, and the spectra of both halides were found to exhibit a single glow peak, with maxima at 140 and 124 ° K respectively.
TL;DR: In this paper, the preparation of iron(III), iron(II), nickel(II, copper(I) and copper(II) complexes with thiomorpholin-3-one is described.
TL;DR: I batteri simbionti endocellulari dei Blattoidei svolgono attività proprie dei mitocondri ossidando attivamente l'α-ketoglutarato, l'isocitrato, incrementando l'attività succino-ossidasica, citocromo-C ossidasica e the concentrazione di ATP nel tessuo ospite
Abstract: I batteri simbionti endocellulari dei Blattoidei svolgono attivita proprie dei mitocondri ossidando attivamente l'α-ketoglutarato, l'isocitrato, incrementando l'attivita succino-ossidasica, citocromo-C ossidasica e la concentrazione di ATP nel tessuo ospite rispetto a quello aposimbiotico. Il metabolismo del glucoso e del glucoso-6-fosfato e efficiente solo in presenza dei simbionti. La concentrazione di glucoso-6-fosfato e maggiore nel tessuto simbiotico.
TL;DR: In this paper, the thermoluminescence spectrum of X-irradiated urea in the interval between N 2 liquid temperature and room temperature was obtained using both the initial rise and the May and Partridge methods.
TL;DR: In this article, a new procedure is proposed with the aim of taking full advantage of all the information at hand, based on the grouping of stations exhibiting homogeneous characteristics and on the use of the one-day rainfall characteristics available from the much more numerous non-recording stations.
TL;DR: A [Cr(H2O)6]Cl3 aqueous solution, 0.25 M at T = 20°C, is investigated by X-ray diffraction as discussed by the authors.