Behavior pattern, arterial partial pressure of oxygen, superoxide dismutase, micro-blood-flow state and longevity or aging.

It is believed that the mechanisms of aging or longevity are multifactorial. We selected four major postnatal factors to verify the mechanisms of longevity and aging. Type B behavior is strongly associated with longevity. The frequency of Type B behavior pattern (55.5 vs. 26.6%) was significantly higher while Type A behavior pattern (2.4 vs. 5.9%) was much lower in the longevity group compared with those in the elderly group (P < 0.01). The decline of arterial partial pressure of oxygen (PaO2) might relate to the aging process which was supported by two facts: (1) low PaO2 might lead to high frequency of chromosomal aberrations, the frequency of chromosomal aberrations was 1.22+/-0.53%, 0.57+/-0.23% and 0.23+/-0.22% in PaO2 < 75, 75-84 or > or = 85 mmHg groups respectively (P < 0.025); (2) the lower the PaO2, the more serious the retina arteriosclerosis. Five mean contents of superoxide dismutase (SOD) in erythrocytes were 626+/-39, 583+/-56, 556+/-43, 547+/-49 and 557+/-40 microg/gHb in different age groups. No significant differences were found in the longevity group as compared with those in 40-89 years old age groups (P > 0.05), but a significantly lower level was found in the middle rather than the young age group (P < 0.05). The studies of thixotropy show that micro-blood-flow state also sustains a better condition in the longevity group. We consider Type B behavior pattern, a higher PaO2, a better micro-blood-flow and a higher level of SOD of erythrocytes may be beneficial for longevity.