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1.
J Clin Pharmacol ; 31(2): 136-9, 1991 Feb.
Article in English | MEDLINE | ID: mdl-1672698

ABSTRACT

The current study evaluated the effect of two beta adrenergic-blocking agents, propranolol (PRP) and atenolol (ATN), versus placebo on cerebral blood flow (CBF) of three homogeneous groups of cirrhotic patients with portal hypertension. CBF was measured by the noninvasive 133-Xenon inhalation method at rest and 1 hour after a single oral dose of PRP (40 mg), or ATN (100 mg), or placebo. Blood pressure and heart rate (HR) were measured at the beginning of each examination, and end-tidal pCO2(PeCO2) was monitored. The HR decreased significantly in both the PRP and ATN groups (P less than .01), whereas no changes were recorded for both PeCO2 and mean arterial blood pressure (MABP). The comparisons of the CBF differences among groups (ANOVA with the significance levels adjusted by the Bonferroni's correction) showed a significant increase in CBF after ATN as compared with both placebo (P less than .02) and PRP (P less than .01), whereas no significant differences were seen after PRP as compared with placebo. Our results confirm that PRP does not significantly affect CBF, whereas ATN induces an increase in CBF, although the underlying mechanism is difficult to explain.


Subject(s)
Atenolol/pharmacology , Cerebral Cortex/blood supply , Hypertension, Portal/complications , Liver Cirrhosis, Alcoholic/complications , Propranolol/pharmacology , Adrenergic beta-Antagonists/administration & dosage , Adrenergic beta-Antagonists/pharmacology , Adult , Aged , Atenolol/administration & dosage , Blood Pressure/drug effects , Cerebrovascular Circulation/drug effects , Female , Heart Rate/drug effects , Humans , Male , Middle Aged , Propranolol/administration & dosage
2.
Ital J Neurol Sci ; 10(4): 415-21, 1989 Aug.
Article in English | MEDLINE | ID: mdl-2793414

ABSTRACT

Cerebral blood flow (CBF), measured by the non-invasive 133-Xenon inhalation method, plasma levels of ammonia (NH3) and free tryptophan (fTRP) were determined in 30 cirrhotic patients without overt encephalopathy. Psychometric evaluation detected subclinical hepatic encephalopathy (SHE) in 20 of them, and was normal in the other 10. A significant CBF difference (p less than 0.05) was found between the SHE and the non-SHE patients. fTRP levels were significantly (p less than 0.05) higher in patients with SHE than in those without SHE, and a significant negative correlation (p = 0.003) was found between CBF values and fTRP in the whole group of patients. NH3 did not differ in the two subgroups and did not correlate with CBF values. It is concluded that CBF could have some implications in SHE, although its relevance is still unclear. The negative correlation between CBF and fTRP prompts further investigation concerning the relationships between plasma fTRP, brain serotonin, cerebral metabolism and blood flow in the development of brain derangement during cirrhosis.


Subject(s)
Cerebrovascular Circulation , Hepatic Encephalopathy/physiopathology , Liver Cirrhosis, Alcoholic/physiopathology , Tryptophan/blood , Adult , Aged , Female , Hepatic Encephalopathy/diagnostic imaging , Hepatic Encephalopathy/etiology , Humans , Liver Cirrhosis, Alcoholic/blood , Liver Cirrhosis, Alcoholic/complications , Male , Middle Aged , Radionuclide Imaging , Xenon Radioisotopes
3.
J Cereb Blood Flow Metab ; 9(3): 410-6, 1989 Jun.
Article in English | MEDLINE | ID: mdl-2715210

ABSTRACT

Regional CBF (rCBF) was evaluated by the 133Xe inhalation method in 60 neurologically normal patients (30 men and 30 women) and hemispheric and regional values were correlated with anxiety measurements collected by a self-rating questionnaire before and after the examination. Statistically significant negative correlations between rCBF and anxiety measures were found. rCBF reduction for high anxiety levels is in line with results previously reported by others and could be related to lower performance levels for moderately high anxiety scores as those reported in the present population. This could perhaps be explained by rearrangement of flow from cortical zones to deeper areas of the brain, classically known to be implicated in the control of emotions. However, these results should be interpreted cautiously, since they were obtained in patients and not in normal subjects.


Subject(s)
Anxiety/physiopathology , Cerebrovascular Circulation , Adult , Aged , Female , Frontal Lobe/blood supply , Humans , Male , Middle Aged , Occipital Lobe/blood supply , Parietal Lobe/blood supply , Regression Analysis , Surveys and Questionnaires , Temporal Lobe/blood supply , Xenon Radioisotopes
4.
J Cereb Blood Flow Metab ; 7(6): 768-72, 1987 Dec.
Article in English | MEDLINE | ID: mdl-3693432

ABSTRACT

Cerebral blood flow (CBF), measured by the noninvasive xenon-133 inhalation method, EEG, and plasma levels of ammonia (NH3) and free tryptophan were determined in 18 hospitalized cirrhotic patients affected with subclinical hepatic encephalopathy, as diagnosed by the Kurtz test. CBF results were significantly lower (p less than 0.001) in the patients' group as compared with a sex- and age-matched normal control population, although seven patients had values in the normal range. NH3 was increased only in six, while free tryptophan was increased in all but two patients. A significant negative correlation (p = 0.02) between CBF and free tryptophan was found, even though it appears to be difficult to interpret. We suggest that CBF impairment in some cirrhotic patients with subclinical hepatic encephalopathy may be related to the systemic metabolic derangement caused by the liver disease; free tryptophan could have some implication in producing CBF reduction.


Subject(s)
Cerebrovascular Circulation , Hepatic Encephalopathy/physiopathology , Tryptophan/blood , Adult , Aged , Ammonia/blood , Blood Flow Velocity , Electroencephalography , Female , Humans , Male , Middle Aged , Xenon Radioisotopes
5.
Surg Neurol ; 24(2): 211-7, 1985 Aug.
Article in English | MEDLINE | ID: mdl-4012580

ABSTRACT

Seventeen patients with minor cerebral contusion were selected from a series of patients with head injuries of various severity, who had undergone repeat evaluations of the regional cerebral blood flow. The mean global flow (expressed as mean global initial slope index) on early examination was found to be significantly lower, compared with that recorded in healthy volunteers. A tendency towards the recovery of higher flow values was apparent in repeat evaluations that were performed several weeks after the injury. Interhemispheric asymmetries of flow were a common occurrence, with lower perfusion and reduced attenuation values on computed tomography scans being, however, in good agreement only in approximately half of the cases.


Subject(s)
Brain Concussion/physiopathology , Cerebrovascular Circulation , Adolescent , Adult , Brain Concussion/diagnostic imaging , Brain Concussion/psychology , Consciousness , Female , Humans , Longitudinal Studies , Male , Orientation , Time Factors , Tomography, X-Ray Computed
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