0000000000497699
AUTHOR
K. Lowitzsch
Hypokalemia shortens relative refractory period of peripheral sensory nerves in man
Absolute and relative refractory periods and the sensory conduction velocity of the median and ulnar nerves were determined in six patients suffering from hypokalemia of various origins. Nerve impulse conduction and the absolute refractory period remained normal, but the relative refractory period was shortened to 1.7 to 2.6 ms at serum K+ levels from 1.6 to 2.9 mval/l. As compared with normal values this decrease was statistically significant.
ERG und VEP in der Topodiagnostik des visuellen Systems
Das visuelle System mit Rezeptorapparat und retino-kortikalen Projektionsbahnen stellt ein sehr komplexes Beispiel der zentralnervosen Informantionsverarbeitung dar. Dabei sind die anatomischen Strukturen und die sinnesphysiologischen Mechanismen weitgehend aufgeklart und analysiert. Krankheitsprozesse auf den verschiedensten Ebenen der neuronalen Verarbeitung von Sehreizen fuhren zu Sehstorungen, deren Abklarung zunachst in topographischen Dimensionen erfolgt, ehe atiologische Faktoren eruiert werden.
Changes of sensory conduction velocity and refractory periods with decreasing tissue temperature in man.
Changes with temperature of maximum sensory nerve conduction velocity as well as absolute and relative refractory periods were tested in 14 human subjects. Corresponding to previously published findings maximum conduction velocity decreased with cooling following a Q10 of +1.4. The absolute and relative refractory periods were increased by cooling, the Q10 being -3.1 and -3.35 respectively. There was a tendency showing a more pronounced temperature effect at low temperatures. The Q10 and the steepness of the regressionline changed at the level of 26.9 degrees C, but were significant for the relative refractory period only.