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Biomedical subjects

H Franke

Publications and source records attributed to H Franke.

247 records · Page 14Linked to original sources
PubMedDate not supplied

Morphological alterations of neurons and astrocytes and changes in emotional behavior in pentylenetetrazol-kindled rats.

Changes of emotional behavior and neuronal cell loss in the hippocampus were investigated after pentylenetetrazol (PTZ) induced kindling in rats. Behavioral and morphological changes were studied in partially and fully kindled rats and after different postkindling periods comparing to the controls. The resident-intruder test indicated a diminished offensive behavior in partially and fully kindled animals. The open-field and the cat-odor exposition tests reveal changes in defensive behavioral pattern only in fully kindled rats. A decrease of exploratory locomotion and an increase in freezing were assessed in the open-field and the cat-odor exposition test, respectively, up to 10 weeks after the end of kindling. The first damaged neurons (CA4 region) were observed in the partially kindled group (PK), correlating with an increase in the glial fibrillary acidic protein (GFAP)-immunoreactivity (GFAP-IR) and hypertrophy of astrocytes. The most significant increase in the number of damaged neurons was detected 24 h after completion of kindling (selective vulnerability: CA4/CA1>DG>CA2+CA3). The neuronal loss went on for 10 weeks postkindling. A low correlation between the number of Stage 4 kindling seizures and the number of damaged hippocampal neurons was found 24 h after the end of kindling in individual rats. The present results demonstrate that PTZ kindling goes along with long-lasting changes in emotional behavior. The alterations of the defensive behavior after the termination of kindling can be interpreted as depression-like and are obviously associated with a characteristic pattern of neuronal loss in various hippocampal regions.

Animals↗
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The reaction of astrocytes and neurons in the hippocampus of adult rats during chronic ethanol treatment and correlations to behavioral impairments.

Chronic ethanol treatment of Wistar rats to 10% (v/v) ethanol over a period of 4, 12, and 36 weeks produced distinct alterations of the glial fibrillary acidic protein immunoreactivity (GFAP-IR) of dorsal hippocampal astrocytes. Ethanol consumption over a period of 4 weeks caused an increase in the total GFAP-IR of the astrocytes. Down-regulation of the total GFAP-IR was measured in all examined brain regions after 36 weeks of ethanol treatment. Prolonged ethanol treatment induced a significant loss of the total number of hippocampal pyramidal and dentate gyrus granule cells. Regional differences in the vulnerability to the neurotoxic effects of chronic ethanol intake over 36 weeks were found: CA3 > CA1 + CA2 > > CA4 > GD. In agreement with the degree of neuronal cell loss, ethanol-induced behavioral impairments were found. The acquisition of maze performance using a complex elevated labyrinth was deteriorated after 36 weeks of ethanol treatment, suggesting a deficit in learning and memory. These findings illustrate the importance of time-response analysis when determining the structural and functional changes produced by chronic ethanol treatment.

Animals↗
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[Sleep in old age].

Explore the source record for details and available documents.

Age Factors↗
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Glucagon induced functional changes of isolated perfused rat kidney.

The influence of glucagon on renal function and hemodynamics was studied on isolated perfused rat kidneys. During perfusion with solutions containing no vasoactive substances glucagon increased total renal perfusion flow, while the GFR remained unchanged. The autoregulation of blood flow under these conditions was completely abolished. Na-excretion was slightly reduced under the action of glucagon, due to an increased fractional Na-reabsorption. However, increased fractional Na-reabsorption was not due to a direct influence of glucagon on tubular transport mechanism as comparison of TNa at identical Na-loads demonstrated. In presence of angiotensin II renal perfusion flow was markedly reduced and doubled almost after starting glucagon infusion. GFR under these conditions rose by about 100%. It is concluded from the results that changes of kidney function following glucagon infusion are mainly due to a reduced vascular resistance.

Animals↗
PubMedDate not supplied

Investigation in healthy volunteers to evaluate serum concentrations and urinary excretions of aluminium, magnesium, calcium and phosphate after multiple administration of hydrotalcit (Talcid) suspension.

The aim of this study was to evaluate the extent of aluminium absorption after repeated administration of Talcid suspension. Therefore, the serum concentrations of aluminium and the amount of urinary excreted aluminium were determined. Furthermore, the influence of repeated Talcid administration on serum concentrations and urinary excretion of magnesium, calcium and phosphate was studied. The trial was carried out as a randomized, double-blind, parallel-group, placebo-controlled investigation in 17 healthy male volunteers and 1 female volunteer, aged between 18-34 years.

Adolescent↗
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[Recent problems of advanced age in humans. I. General problems].

The obvious increase of human age even up to above one hundred years in nearly all civilised countries leeds the autor to discuss the following actual gerontologic problems: the needs for further splitting of categories of high age, the reasons for the rapid increase of the oldest-old group and the predicted "mushroom"-shaped age-pyramid in Germany. Further subjects are the liability of age-declaration in the highest age group according to the strict directions by Kannisto, the total account of men and women above one hundred years of age in different countries and in Germany since 1963, the difference between relative and absolute longevity and new molecular-biologic and genetic studies on extreme age.

Aged↗
PubMedDate not supplied

[New special research data on over 100-year-old and older probands and problems (II)].

The critical evaluation of all so-called correlation factors of the absolute longevity of centenarians lead to the assumption that those of extreme age among the oldest elderly remain as a biological selection of the total population. Due to an unfavorable biological total constellation, the comparable oldest elderly have already died. To solve these selection problems, research reports in this country and abroad are helpful in relation to this special category of centenarians. New findings in laboratory diagnostics, the genetic privileged position of long-living persons regarding their expectancy re arteriosclerosis, as well as the modern molecular biological and neuropathological cerebral studies of deceased persons of the oldest category can be regarded in the sense of a selection of elderly people. The characteristics of the central nervous system, the cardiovascular and pulmonary system of the elderly, give an indication (e.g., of a 100-years-old smoker) of the extreme living conditions of the oldest elderly. A large number of curiosities found in the literature and personally observed unexplainable findings illustrate the remarkable lifestyle of individually selected oldest elderly. The final section discusses the biological, social and psychological special position of the oldest elderly.

Activities of Daily Living↗