To investigate the etiologic mechanism of the development of benign nephrosclerosis, kidney weight, the degree of glomerular scarring, the degree of stenosis and hyalinization in the renal small arteries and arterioles were quantitatively determined in 222 autopsies, who were followed up in the 10 years 1961 thruogh 1971 in Hisayama Study. They were analyzed in relation to age at time of death, ante-mortem blood pressure level, results of glucose tolerance test and proteinuria. Results obtained were as follows; 1) Glomerular scarring and the stenosis of small arteries became prominent with increasing age accompaning a reduction in kidney weight, and they were more marked in hypertensive than in normotensive group at each decade. The stenosis and hyalinization of arterioles were always affected by hypertension, but they had no relation in aging process. 2) Arteriolar nephrosclerosis constantly developed in diastolic hypertensive persons without relation in age, but arterial nephrosclerosis was found in older age group independently of blood pressure level. The persistent high blood pressure had effect on the development of nephrosclerosis. 3) Four cases of severe diabetic glomerulosclerosis were observed in 35 autopsies with diabetes mellitus, most of which were latent chemical. Glomerular scarring and arteriolar hyalinization were prominent in diabetic than in control group. 4) Slight or intermittent proteinuria was noted more eminent with increasing age, and more frequent in hypertensive than in normotensive group. Persistent proteinuria was found only in diabetic nephrosclerosis. 5) The prognosis of benign nephrosclerosis was affected by complicated cerebrovascular disease. But there was no case, which terminated to death caused by nephrosclerosis.
The disturbance of the responses for the cold stress are more distinguished than these for the heat stress in the aged, and the principal characteristic of the thermoregulation in the aged is the suppressed responses resulted from the decrease of the sensibility for the thermal stimuli. But the regulatory mechanismus, which chalacterize the temperature regulation in the aged, was not investigated in detail till now. On the other hand the distribution of the sensory points in various cutaneous area, was already investigated minutely in the 1920's, and after that the investigation about the cutaneous sensation is mainly concerned with the problemes of electrophysiological characteristics of the sensory receptors. The effect of aging on the threshold of cutaneous sensation was also reported from several investigators, but there is no report about the effect of aging on the distribution of sensory points. As the first trial for studing the characteristic of the thermoregulatory mechanism in the aged, the frequency of the cutaneous cold points and, for the comparison, also of cutaneous pain points in the aged was investigated. The test was performed in 8 areas of the body surface, i.e, forehead, neck, breast, belly, forearm, back of hand, calf and back of foot of each peoples both of the aged group of 30 peoples (73±4 years old) and of the control group of 20 peoples (26±5 years old). To estimate the frequency of the cold and pain points, the number of the points, which could be perceived cold or pain resp., in 100 trials in 2×2cm square area was measured. The results obtained was as follows: 1) The decrease of the frequencies of both cold and pain points of the aged group in comparison with these of the control group is significant in all area, except in the pain point of the forehead. 2) The frequency of the cold points was higher in the body trunk area and lower in the peripheral extremity area, especially in the calf and in the back of foot. The decrease of the frequency of the cold points in the aged group was marked also in the calf and in the back of foot. 3) The regional difference of the frequency of the cutaneous pain points and the decrease of the frequency of the pain points in the aged is less distinguished than these of the cold points. But the frequency of the pain points in the back of foot is markedly low and decreased markedly in the aged. The results suggest that the decrease of the cold points is affected to the suppressed sensibility for the thermal stimuli and that there is a cutaneous regional difference in the distribution of the sensory points and in their decrease through aging.