Search PubMed⌕ Search

Biomedical subjects

M Rossor

Publications and source records attributed to M Rossor.

82 records · Page 5Linked to original sources

Reduced cortical choline acetyltransferase activity in senile dementia of Alzheimer type is not accompanied by changes in vasoactive intestinal polypeptide.

Post-mortem brain tissue from 7 patients who died with a diagnosis of senile dementia of Alzheimer type (SDAT) was compared with tissue obtained from 7 control patients at routine post mortem. A significant fall in choline acetyltransferase (ChAT) activity was apparent in the cerebral cortex of the SDAT cases which was maximal in the temporal lobe. The fall in ChAT activity was not accompanied by changes in cortical vasoactive intestinal polypeptide (VIP) measured by radioimmunoassay.

Aged↗

Benzodiazepine receptors: the effect of GABA on their characteristics in human brain and their alteration in Huntington's disease.

The characteristics of bezodiazepine (BDZ) receptors were studied in the putamen and substantia nigra (SN) of control and Huntington's disease (HD) human brains. In the putamen, there was a significant decrease in density BDZ receptors in the HD tissue. In addition the application of GABA significantly potentiated DBZ receptor binding in both the HD and control putamen. In the SN, an increase in BDZ receptor density was detected in the HD tissue. GABA enhanced [3H]flunitrazepam binding in both the HD and control SN by increasing the affinity of BDZ receptors for [3H]flunitrazepam. The results suggest that there are alterations in BDZ receptors in HD human brain and that these alterations may be related to the neuronal pathology of this disease. This study also provides evidence for a coupling of GABA receptors to BDZ receptors in human brain.

Aged↗

Regional distribution of methionine-enkephalin and substance P-like immunoreactivity in normal human brain and in Huntington's disease.

The regional distributions of substance P and Methionine-enkephalin (Met-enkephalin) were determined in normal human brains and in Huntington's disease using sensitive radioimmunoassays. Model experiments showed that both Met-enkephalin- and substance P-like immunoreactivities were stable for up to 72 h post-mortem in mouse brain. The results of high pressure liquid chromatography (HPLC) analyses indicated that the majority of the immunoreactivity detected in human globus pallidus corresponded to the native peptides, substance P or Met-enkephalin. In Huntington's disease the present results confirm that there is a substantial drop (> 80%) in the substance P content of the globus pallidus (both medial and lateral segments) and substantia nigra, and there was also a reduction (> 50%) in the Met-enkephalin content of these areas. This result suggests the loss of striato-pallidal and striato-nigral substance P and enkephalin-containing projections in Huntington's disease.

Animals↗

No evidence for lateral asymmetry of neurotransmitters in post-mortem human brain.

A study of post-mortem human brain was undertaken to establish whether there is any evidence for lateral asymmetry of neurotransmitters. Choline acetyltransferase, glutamic acid decarboxylase, alpha-aminobutyric acid, dopamine and noradrenaline were measured in nine comparable areas from the left and right hemispheres of normal post-mortem human brain. Only nigral GABA showed a left-right difference at a significance level of 5%. These negative post-mortem findings suggest that chemical laterality is unlikely to be an important source of error in human post-mortem studies.

Aged↗

The effects of donepezil in Alzheimer's disease - results from a multinational trial.

Donepezil has been shown to be well tolerated and to improve cognition and global function in patients with mild to moderately severe Alzheimer's disease (AD). The current trial was undertaken to investigate further the efficacy and safety of donepezil, in a multinational setting, in patients with mild to moderately severe AD. This 30-week, placebo-controlled, parallel-group study consisted of a 24-week, double-blind treatment phase followed by a 6-week, single-blind, placebo washout. Eight hundred and eighteen patients with mild to moderately severe AD were randomly allocated to treatment with single, daily doses of 5 or 10 mg donepezil, or placebo. The two primary efficacy measures were: a cognitive performance test, the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) and a global evaluation, the Clinician's Interview-Based Impression of Change with caregiver input (CIBIC plus). Secondary outcome measures included the Sum of the Boxes of the Clinical Dementia Rating Scale (CDR-SB), a modified Interview for Deterioration in Daily living activities in Dementia (IDDD) and a patient rated quality of life assessment. Statistically significant improvements in cognitive and global function were observed, as evaluated by ADAS-cog and CIBIC plus, respectively, in both the 5 and 10 mg/day donepezil groups, compared with placebo. Treatment-associated changes were also observed in functional skills, as shown by improved scores on the CDR-SB and the complex-tasks component of the IDDD. A dose-response effect was evident, with the 10 mg/day donepezil group demonstrating greater benefits in all outcome measures than the 5 mg/day group. Donepezil was well tolerated by this patient population and did not produce any clinically significant laboratory test abnormalities. The results of this study confirm that donepezil is effective and well tolerated in treating the symptoms of mild to moderately severe AD.

Aged↗