Abstract
A cytomorphometrical study was made on the hepatocyte of 9 centenarians (3 males, 6 females; 100-112 years old) with no significant alterations in the liver and the results were compared with those obtained from 34 non-centenarians (17 cases each for both sexes; 16-92 years old).
Both nuclear and cellular areas of the hepatocyte were measured on histological sections by the cytophotometrical method using a QTM-900 (Metal Res., England). The results were as follows:
1) All cytophotometrical parameters estimated, which include the nuclear and cellular size and their mean values, were greater than those of non-centenarian groups.
2) The nucleo-cellular ratio differed insignificantly from those of non-centenarian groups.
3) An incidence of binucleate cells was greater than those of non-centenarian groups and its increase was proportionate with grades of polyploidization observed in mononuclear hepatocytes of the same individual.
4) The greatest ploidy class detected was 16C in mononuclear cells and (8C+8C) in binucleate cells.
All these data show that size alterations of the hepatocyte of centenarians follow an increasing pattern in proportion to aging observed in non-centenarian groups. Thus the centenarian could be a group locating on an extending position next to the nonagenarian. The results obtained by present cytomorphometrical analysis do not favor a hypothesis that the centenarian is a select population in terms of longevity.
