Ultrastructural reorganizations in the rat cerebral cortex after injection of ascorbic acid into the ventricular fluid.
A brief increase in the ascorbic acid concentration in the rat cerebral cortex after intraventricular bilateral injection of 20 microliters of a 0.1% or 1% ascorbic acid solution and also intracisternal injection of 20 microliters of a 0.5% solution results in a prolonged (not less than 21 days) ultrastructural reorganization in the nucleus and cytoplasm of the cortical neurons: the amount of lysosomes, polysomes, vesicles of the Golgi complex, and subsurface cisterns increases, this demonstrating an increasing RNA and protein synthesis, catabolic processes, and neuronal-glial interaction. Changes in the ultrastructure of the synaptic terminals, such as disintegrating mitochondria, formation of myelin-like bodies, and, in addition, after interstitial injection, protrusions into the adjacent dendrite, demonstrate that synapses are one of the sites where excess ascorbic acid affects the CNS. Over a long period, 3 and 6 months after injection, the changes mentioned are not observed but in the glial processes one can observe vacuoles containing degenerating elements.
Grigor'ev
I P
IP
Department of Morphology, Academy of Medical Sciences of the USSR, Leningrad.
D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000378:metabolism / Q000648:ultrastructure*; D002843:Chromatin / Q000187:drug effects / Q000648:ultrastructure; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000648:ultrastructure; D006863:Hydrogen-Ion Concentration; D007276:Injections, Intraventricular; D051381:Rats; D011919:Rats, Inbred Strains; D013569:Synapses / Q000187:drug effects / Q000648:ultrastructure
D002843:Chromatin; D001205:Ascorbic Acid