No abstract

Abstract— Using a two‐wavelength modification of ultraviolet and visible cytospectro‐photometric methods, the content of nucleic acids per cell was determined in neuronal cytoplasm and glial satellite cell‐bodies from the spinal cord anterior horns in mice and rats. Mice which had been swimming for 3 and 4 h showed an increase in the content of RNA in the spinal motoneurons with no changes in the neuroglia. Stronger stimulation of the nervous system such as electrical skin irritation (20‐40 V, approx. 40 impulses/min) for 5 min resulted in an increase of RNA in the motoneurons of rat spinal cord and a decrease in the surrounding glia. Exhausting actions upon the nervous system (60 min irritation of rat paws by the electrical current, acute clonic convulsions in rats injected with cardiazol (pentamethylenetetrazol, metrazol) or initial free motor activity after 3 weeks of restraint of mice) induced a marked decrease of RNA content throughout the whole neuron‐neuroglia unit. After stimulation, return to normal amounts of RNA and protein was more rapid in glia than in neurons. After 1‐3 days rest the level of RNA was normal in motoneurons, but a decrease in glial RNA was shown. These trace changes in the glia are believed to reflect an adaptation mechanism in the nervous system at the cellular level. The relationship between neuronal and glial compartments within the neuron‐neuroglia unit is discussed; a supporting, homeostatic, secondary role of glial metabolism with respect to adequate reconstruction of neuronal metabolism is outlined.

No abstract

No abstract