Pii: S0304-3940(00)01116-2
نویسندگان
چکیده
Nuclear and perikaryal volumes, as well as the mean percentage of perikaryal volume occupied by lipofuscin, were estimated in spinal ganglion neurons of 12, 42 and 79 month-old rabbits. The volume ratio between nucleus and perikaryal cytoplasm (N/C volume ratio) decreased progressively and signi®cantly with increasing age. This was not a consequence of the perikaryal enlargement due to the age-related lipofuscin accumulation since the same result was obtained when the volume occupied by lipofuscin was subtracted from the perikaryal volume. The decrease in the N/C volume ratio may depend on an age-related loss of DNA, a cytoplasmic in ̄uence on nuclear size, or other unknown causes. q 2000 Elsevier Science Ireland Ltd. All rights reserved.
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