Search

Associations in 52 normal individuals were examined between plasma and cerebrospinal fluid (CSF) concentrations of tryptophan (Trp) and tyrosine, and concentrations of monoamine metabolites in the CSF, and scores on an aggression questionnaire, the Kinsey Institute Reaction List II, and the Eysenck Personality Questionnaire. There was a significantly positive correlation between CSF 5-hydroxyindoleacetic acid (5-HIAA) levels and extroverted aggression scores, and a significantly negative correlation between CSF 5-HIAA levels and introverted aggression scores. Males showed higher plasma Trp concentrations than females, and significantly positive correlations between plasma Trp concentrations and scores on extroverted aggression and the Eysenck E scale. Males, furthermore, showed a significantly negative correlation between CSF Trp levels and scores on the Eysenck P scale, and a significantly positive correlation between concentrations of 3-methoxy-4-hydroxy-phenylglycol in CSF and scores on moral aggression. These results suggest that central serotonin influences aggression in normal individuals through effects on personality.

Associations in 52 normal individuals were examined between plasma and cerebrospinal fluid (CSF) concentrations of tryptophan (Trp) and tyrosine, and concentrations of monoamine metabolites in the CSF, and scores on an aggression questionnaire, the Kinsey Institute Reaction List II, and the Eysenck Personality Questionnaire. There was a significantly positive correlation between CSF 5-hydroxyindoleacetic acid (5-HIAA) levels and extroverted aggression scores, and a significantly negative correlation between CSF 5-HIAA levels and introverted aggression scores. Males showed higher plasma Trp concentrations than females, and significantly positive correlations between plasma Trp concentrations and scores on extroverted aggression and the Eysenck E scale. Males, furthermore, showed a significantly negative correlation between CSF Trp levels and scores on the Eysenck P scale, and a significantly positive correlation between concentrations of 3-methoxy-4-hydroxy-phenylglycol in CSF and scores on moral aggression. These results suggest that central serotonin influences aggression in normal individuals through effects on personality.

BACKGROUND: The 21-aminosteroids are a series of compounds designed to inhibit lipid peroxidation in the cell, and, as such, may have cerebral protective effects. The current study was performed to evaluate the effect of a 21-aminosteroid, tirilazad mesylate (U74006F), on cerebral blood flow, metabolism, and carbon dioxide reactivity.METHODS: Using a double-blind study design, eight volunteers received tirilazad mesylate, and eight others received only vehicle. The cerebral blood flow was measured by single photon emission computerized tomography using 133Xe inhalation in the resting condition at the beginning of the study and after infusion of tirilazad mesylate (1.5 mg/kg) or vehicle. Cerebral oxygen metabolism was calculated from the cerebral blood flow and the measured cerebral arteriovenous oxygen content difference. After both of the above cerebral blood flow measurements, arterial carbon dioxide tension was decreased by voluntary hyperventilation, and, later, increased by breathing an air/carbon dioxide mixture. The relative changes in cerebral blood flow induced by the PaCO2 variations were estimated from the changes in the arteriovenous oxygen content difference.RESULTS: Blood pressure, pulse rate, and PaCO2 were similar before and after the infusion of tirilazad mesylate in both groups, and there was no difference between the groups. The cerebral blood flow and oxygen metabolism did not change after the tirilazad mesylate infusion. The slope of the regression line of relative change of estimated cerebral blood flow and PaCO2 (regression coefficients in both groups, > 0.90) was unchanged after infusion.CONCLUSIONS: Tirilazad mesylate has no effect on cerebral blood flow, cerebral oxygen metabolism, or reactivity of cerebral blood flow to carbon dioxide in healthy volunteers.

BACKGROUND: The 21-aminosteroids are a series of compounds designed to inhibit lipid peroxidation in the cell, and, as such, may have cerebral protective effects. The current study was performed to evaluate the effect of a 21-aminosteroid, tirilazad mesylate (U74006F), on cerebral blood flow, metabolism, and carbon dioxide reactivity.METHODS: Using a double-blind study design, eight volunteers received tirilazad mesylate, and eight others received only vehicle. The cerebral blood flow was measured by single photon emission computerized tomography using 133Xe inhalation in the resting condition at the beginning of the study and after infusion of tirilazad mesylate (1.5 mg/kg) or vehicle. Cerebral oxygen metabolism was calculated from the cerebral blood flow and the measured cerebral arteriovenous oxygen content difference. After both of the above cerebral blood flow measurements, arterial carbon dioxide tension was decreased by voluntary hyperventilation, and, later, increased by breathing an air/carbon dioxide mixture. The relative changes in cerebral blood flow induced by the PaCO2 variations were estimated from the changes in the arteriovenous oxygen content difference.RESULTS: Blood pressure, pulse rate, and PaCO2 were similar before and after the infusion of tirilazad mesylate in both groups, and there was no difference between the groups. The cerebral blood flow and oxygen metabolism did not change after the tirilazad mesylate infusion. The slope of the regression line of relative change of estimated cerebral blood flow and PaCO2 (regression coefficients in both groups, > 0.90) was unchanged after infusion.CONCLUSIONS: Tirilazad mesylate has no effect on cerebral blood flow, cerebral oxygen metabolism, or reactivity of cerebral blood flow to carbon dioxide in healthy volunteers.