Cytophotometric mapping of neuronal changes in senile dementia

Results of a cytophotometric study have shown a widespread reduction in cytoplasmic RNA of nerve cells. It appears, therefore, that although certain aspects of the symptomatology of senile dementia may be accounted for by lesions in particular anatomical sites, the main part of the neurological disturbance is related to more broadly based changes in nerve cell metabolism affecting much, if not all, of the CNS.

[Physiological and pathological aging of the brain]

Also in the old age, the capability for a meaningful arrangement of life is dependent on the functional integrity of the brain. The processes of senile involution occurring physiologically do not exclude such a possibility. In normal aging, the reduction in the number of nerve cells and dendritic spines is small compared to pathological aging. There are no indications for transitions between normal and pathological aging. Senile dementia is an optionally occurring disease requiring an endogenous component for its manifestation. The psychic peculiarities occurring in the course of normal aging result mainly from environmental factors (i.e. psychic and social injuries). They need multidimentional treatment.

Some cerebral proteins and enzyme systems in Alzheimer's presenile and senile dementia

The water-soluble proteins of the cerebral gray matter and some enzyme systems (cholinesterase, acetylcholinesterase, lactate dehydrogenase, malate dehydrogenase, acid phosphatase) were studied in 9 autopsy cases of Alzheimer's presenile or senile dementia, 1 case of Pick's disease and 1 case of cerebral arteriosclerosis. The proteins and enzyme patterns were visualized on polyacrylamide gradient gels after electrophoresis. In all patients studied, the profiles of cerebral gray-matter proteins were normal. In the patients with advanced dementia, the enzyme patterns usually were abnormal. Particularly in Alzheimer's disease, the activity of malate dehydrogenase was markedly increased.

[Blood flow and oxidative metabolism of the brain in patients with dementia (author's transl)]

The purpose of this retrospective study was to investigate how the blood flow and oxidative metabolism of the brain was changed in dementia and the influence of the age factor. Cerebral blood flow (CBF) was measured in 115 patients aged from 40 to 83 years by means of the Kety-Schmidt technique with the modification of Bernsmeier and Siemons. The cerebral metabolic rates of oxygen and CO2 were determined by the van Slyke method and by gaschromatography respectively and of glucose and lactate by standard enzymatic methods. All cases of dementia due to head injuries, cerebral infections, cerebral infarctions, exogenous or endogenous intoxications or circulatory diseases were excluded from this study, but no classification of the dementias was made. Statistical calculations were carried out by means of the analysis of variance for a two-way design. Cerebral blood flow did not show a normal distribution curve but was at least triphasic; CBF in demented patients was either lower than normal, normal or higher than normal. The distribution curves showed further that a low cerebral blood flow of mean 32.5 ml/100 g min coincided with a low CMR oxygen of 2.50 ml/100 g min; however, CMR glucose was either low (2.50 mg/100 g min), or nearly normal (4.50 mg/100 g min) or elevated (7.50 mg/100 g min). A normal (45.0 ml/100 g min) or enhanced (62.5 ml/100 g min) CBF correlated with a CMR oxygen which was either decreased to 2.75 ml/100 g min or increased to 4.75 ml/100 g min; CMR glucose was either decreased to 1.50 mg/100 g min, or nearly normal (4.50 mg/100 g min), or was elevated to 6.50 and 10.50 mg/100 g min with respect to the peaks of the distribution curves. It is assumed that the variability of the findings with respect to the blood flow and oxidative metabolism of the brain in dementia is due to different pathophysiological and pathobiochemical disturbances in the brain. A significant influence of age on CBF and metabolism in patients with dementia was not found.

The brain ganglioside pattern in presenile and senile dementia

Ganglioside lipid fractions in the cerebral gray matter were studied in 13 patients with various forms of dementia. In 2 patients with Alzheimer's disease and 1 with senile dementia an abnormal ganglioside pattern was observed, i.e., a decrease of G1 and G3 in association with an increase of G2. In the light of the total clinical and histologic data on the patients, it would seem that this disturbance in ganglioside metabolism may be a phenomenon accompanying extensive degradation of brain tissue rather than a factor in the etiology of dementia.

Triiodothyronine turnover in hospitalized psychogeriatric patients

In a group of 12 hospitalized psychogeriatric patients, the fractional triiodothyronine (T3) turnover rate was significantly higher than in healthy control subjects of the same age, whereas the thyroxine (T4) turnover rate and other aspects of pituitary-thyroid function were virtually similar in both groups. Despite the presence of manifestations of sympathetic overactivity or hypermetabolism, the patients did not have true hyperthyroidism, as verified by the laboratory findings and the results of antithyroid treatment. The increases T3 turnover in aged hospitalized patients with brain disorders may be a compensatory mechanism which develops under these particular circumstances in order to maintain neurohormonal homeostasis. An alternate possibility is that the increased T3 turnover is secondary to hyperkinesis.

Measurement of intrathecal I131-albumin transport to plasma. Inability to distinguish cerebral atrophy from communicating hydrocephalus

The transport of intrathecally administered iodine131-albumin to the circulating plasma was measured in five patients with cerebral atrophy and three with communicating hydrocephalus. The percentage of the administered dose in plasma 24 hours after injection in both groups was lower than reported by others in control patients, but the two groups did not differ significantly. The most likely explanation for these results is diminished fractional turnover of CSF per unit time in patients with CSF volume expansion, regardless of cause. This test appears to have no value in differentiating cerebral atrophy from communicating hydrocephalus.