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O Tumilasci

Publications and source records attributed to O Tumilasci.

8 recordsLinked to original sources
PubMed1992

Ethanol and the peripheral benzodiazepine receptor: in vivo and in vitro experiments.

1. The effect of chronic ethanol exposure on rat peripheral benzodiazepine receptors (PBR) was studied. 2. The binding of 3H-RO 5-4864 to PBR was increased (35.4%) in the kidneys of rats treated with 10% (v/v) ethanol for 12 weeks, but not in renal membranes isolated from rats exposed to ethanol 30% (v/v) during the same period. 3. Similarly, short-term administration of ethanol (4 weeks) did not alter the binding of 3H-RO 5-4864 to renal membranes. 4. To examine the possibility of a direct interaction of ethanol with PBR, in vitro experiments were carried out. Only high concentrations of ethanol (> 100 mM) caused a significant inhibition of 3H-RO 5-4864 binding in kidney, testis and cerebral cortex. 5. The results presented indicate that chronic ethanol exposure causes a time and dose-dependent increase in renal PBR.

Animals↗
PubMed1990

Effects of intravenous ethanol on basal bile-pancreatic secretion in nonalcoholic and alcohol-fed rats.

In nonalcoholic (NA) and alcohol-fed rats (AF), intravenous-ethanol-induced percentage changes in bile-pancreatic-secretion (BPS) were evaluated, with and without gastric juice diversion (GJD) and with and without BPS duodenal recirculation (DR). Even with GJD, ethanol elicited a slight increase in BPS. These changes were greater in AF animals even when performed without GJD. When intravenous ethanol was given under conditions of GJD and DR, there were marked differences between the NA and AF animals in the ethanol-elicited post-plateau percentage changes of BPS. NA animals evidenced no significant difference from controls. But in the AF rats, ethanol triggered a marked and significant increase of flow, protein concentration, and output that became progressively greater in successive collection periods. It is postulated that without DR, and the resulting lack of negative duodeno-pancreatic reflexes (DPR), there occurs a change in reactivity to intravenous ethanol of the hypothalamic-bulbar nuclei (HBN) and in the mechanisms that modulate the flow of cholinergic impulses through the intrapancreatic ganglia (IPG). The postulated consequence is predominance (slight in NA rats receiving intravenous ethanol, greater in AF rats) in discharge of positive impulses from HBN and flowing unimpeded through the IPG to the "pancreon" units. In the NA animal with DR, ethanol may enhance BPS values, but in the AF rats, impairment of the negative DPR elicited by chronic alcohol intoxication might, after an acute intravenous ethanol injection, favor the discharge of positive impulses from the HBN flowing unimpeded through the IPG. In the AF rats also, ethanol would activate the nonnicotinic receptors of the neurons of the "antral," "duodenal," and "celiac" autonomic brains.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcoholism↗
PubMed1984

Thyroid hormone regulation of adrenergic receptors and beta-adrenergic responsiveness in the rat submandibular gland.

The effects of altered thyroid function on the sensitivity of isoproterenol induced secretion of saliva and in the characteristics of adrenergic receptors from the rat submandibular gland were examined. Hyperthyroidism produced an increased sensitivity to beta-adrenergic stimulation of the gland, and this phenomenon was associated with an increase in the number of beta and alpha 1-adrenoceptors. On the other hand, surgical thyroidectomy produced a decrease sensitivity to isoproterenol stimulation of the submandibular gland and a diminished density of beta-adrenoceptors. In this case, no changes in alpha-adrenoceptors were observed. These results are discussed emphasizing the correlation between the functional control of saliva secretion and the adrenergic receptors in different thyroid states.

Animals↗
PubMed1984

[Hydroelactic and ecbolic of piprozoline on basal bile-pancreatic secretion in rats].

In male conscious rats provided with a new type of biliary-pancreatic fistula, the effects on basal bile-pancreatic secretion by piprozoline were analyzed when infused intraduodenally superimposed on a "plateau" reached by three previous collection periods of 30 minutes each. Different doses: 25, 50, 100 and 200 mg were evaluated at random during the first 48 hs. of fistula. The secretion evoked by the intraduodenal piprosoline's solvent, propilenglicol, was used as a control reference. The analysis of the percentage secretory changes elicited by piprozoline in respect to the "plateau" put in evidence that this agent exerts a preferential hydrelatic influence namely due to a significant increase in volume. The smallest dose, 25 mg/kg induces a peak volume increase of 30%. The higher dose, 100 and 200 mg/kg give origin to a higher and more sustained response, with peak values of around 70%. Protein and lipase output are also stimulated, but due to a high inter-animal variability the percentage changes are in the borderline of a significant level. It is postulated that piprozoline exerts its influences on basal bile-pancreatic secretion through a stimulation of the hepatic and pancreatic acinar cells and of both hepatic and pancreatic ductal systems. The main mediator of these changes trig by piprozoline would be peptides of the secretin family and duodeno-hepatic and duodeno-pancreatic reflexes. Further clarification through tests in either atropinized or vagotomyzed animals is suggested.

Animals↗
PubMed1982

Catecholamines levels and parotid secretion in children with chronic atopic dermatitis.

The purpose of this study was to evaluate the in vivo state of both branches of the autonomic nervous system in children with chronic atopic dermatitis. In 15 patients, age 4 to 11, the following parameters were analyzed: (1) basal plasma levels of epinephrine, norepinephrine, and dopamine; (2) poststimulation (standing and i.v. furosemide administration); (3) basal urinary excretion of epinephrine, norepinephrine, and vainillin mandelic acid; (4) 30 min postfurosemide administration; (5) parotid secretory response to intraoral 0.1 m citric acid: flow rate, saliva pH, and concentrations of bicarbonate, chlorides, inorganic phosphates, total protein, and amylase activity. No differences in plasma and urinary basal levels of the catecholamines were observed. In response to standing, plasma norepinephrine from atopic children showed a greater increase than that seen in normal healthy children. From the salivary factors studied, no differences were found in parotid flow-rate, bicarbonates, chlorides, and inorganic phosphates. Protein concentration as well as amylase activity were significantly decreased in children with atopic dermatitis. These findings suggest that in atopic dermatitis, the beta-sympathetic mediated responses are impaired; on the other hand, parasympathetic mediated responses remain preserved.

Catecholamines↗