Biomedical subjects

S Poenaru

Publications and source records attributed to S Poenaru.

At least 19 recordsLinked to original sources

PubMed1992

Effects of alcohol dependence on shock-induced fighting: action of muscimol and homotaurine.

We have applied the electroshock-induced fighting behavior to the study of experimental alcohol dependence. Adult Wistar rats were intoxicated chronically with ethanol (10 g/kg/24 h) for 13 days. Electroshock-induced fighting behavior was studied during chronic intoxication and withdrawal in comparison with normal rats receiving a water-carbohydrate solution isocaloric to ethanol. Rats were divided into groups receiving respectively muscimol (0.25 mg/kg), a GABAA agonist; homotaurine (140 mg/kg) a GABA mimetic; and physiological saline (10 ml/kg), intraperitoneally. During chronic intoxication, rats showed an increase in defensive-fighting behavior. Withdrawal accentuated the aggressive behavior and muscimol and homotaurine inhibited it. These results confirm the relevance of the electroshock-induced defensive fighting behavior test in chronic intoxication with alcohol, but to show the involvement of GABAergic transmission in the behavioral effects of alcohol withdrawal, additional experiments with other GABA mimetics and with GABA antagonists should be considered.

Aggression↗

PubMed1990

Circadian variations in vigilance states in the alcohol-dependent rat.

Waking and sleep states were studied in the alcohol-dependent rat after administration of ethanol (416 mg/kg/hr) by indwelling intragastric catheter (IGC) for 13 days. Electropolygraphic recordings performed for a total of 24 hr from the start of withdrawal were compared with those of control rats receiving water by IGC and showed 1) that rapid eye movement sleep was the most sensitive of the four vigilance states studied. A decrease was noted both for the total duration of recording and for the light period; 2) that nonactive wakefulness was the only vigilance state to show an inversion of percentages between the light and dark period; 3) that the light period was the best time for studying changes in vigilance states. Changes included increased percentages of active and nonactive wakefulness and decreased percentages of slow-wave and rapid eye movement sleep. This was due to a change in the number of episodes rather to a change in their mean duration. No significant change occurred during the dark period.

Alcohol Withdrawal Delirium↗

PubMed1984

Vigilance states and cerebral monoamine metabolism in experimental magnesium deficiency.

Correlations between cerebral monoamine metabolism and electrophysiological parameters were compared in 18 male Wistar rats subjected to a magnesium-restricted diet and in 14 normal rats. During the 40-day experimental period, plasma and erythrocyte Mg2+ levels and plasma Ca2+ and phosphorus levels were measured, and electroencephalographic tracings as well as clinical data were recorded at regular intervals. At the end of the study, the animals were killed and cerebral concentrations of monoamines and their metabolites were determined. Cerebral monoamine disorders characterized by a rise of dopamine and 5-hydroxyindole-3-acetic acid levels were observed in the magnesium-deficient group. This rise was accompanied by an increase in wakefulness and a decrease in sleep percent. The role played by magnesium in cerebral monoamine metabolism and sleep cycles is discussed.

3,4-Dihydroxyphenylacetic Acid↗

PubMed1976