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M Danzeisen

Publications and source records attributed to M Danzeisen.

4 recordsLinked to original sources
PubMed1979

Dopaminergic agonists and their influence on the oxygenation and function activity of underperfused brain tissue.

The effect of two dopaminergic agonists (apomorphine and bromocriptine) on electrical activity and oxygen supply of the brain was investigated in cats submitted to hypovolemic oligemia (mean arterial blood pressure: 45 mmHg). While both drugs stimulated the brain by prolonging the oligemia-induced seizures in the caudate nucleus and in the cerebral cortex, only apomorphine improved the pO2 distribution in the cortical tissue after 120 min oligemia. Bromocriptine, in contrast, had a beneficial effect of shorter duration. These data show that under conditions of incomplete ischemia the brain can still be activated. Furthermore, these results provide additional support for the biochemically founded hypothesis of different dopamine receptors in the brain.

Animals↗
PubMed1978

Effect of carotid ligation on cerebral tissue oxygenation in aging rat.

In order to test the ability of aged animals to compensate a cerebrovascular insufficiency, common carotid ligation was performed on young (12 months) and aged (30 months) rats. By using gold microelectrodes, the pO2 distribution in the cerebral cortex was registered for 1 h following the occlusion of the carotid arteries. It could be shown that, while the young group was able to compensate the reduction in arterial blood supply, the cortical pO2 distribution in the group of aged rats shifted towards a hypoxic profile. These results provide further evidence of the limited adaptability to functional demands with increasing age.

Aging↗
PubMed1978

Cortical pO2 distribution during oligemic hypotension and its pharmacological modifications.

pO2 measurements in the cerebral cortex of cats have shown that the distribution of oxygen within the tissue becomes considerably affected by hypovolemic hypotension, in particular in the late period of oligemia. Pharmacological studies on this model show that the treatment of shock with a vasodilating drug such as papaverine leads to shunt-perfusion, thus impairing the oxygenation of brain tissue. In contrast, administration of the metabolically active drug dihydroergotoxine (DET, Hydergine) results in an improvement of the tissue pO2 distribution in the direction of a pre-shock state.

Animals↗