<Short Report>Age-related Changes in Serum Lipids and Longevity in Hepatectomized Rats

The life span and serum lipids of Sprague-Dawley rats was examined following partial hepatectomy. Adult Sprague-Dawley rats were divided into two groups. One group received a 30% partial hepatectomy (30H) and the other underwent sham-surgery(control). Moreover, group 30H rats were divided into two subgroups based on length of survival ; a short life span group (30HS, n=4), and a long life span group (30HL, n=4). Blood was collected at 24 weeks after partial hepatectomy, and effects on serum biochemical parameters and longevity were evaluated. The 30HS group gained weight more rapidly than the 30HL group. Serum lipids in the 30HS group were higher than those in the 30HL group. These results indicate that survival rate may be related to early changes in lipid metabolism after partial hepatectomy

Effects of Green Tea Fractions on Oxygen-Induced Retinal Neovascularization in the Neonatal Rat

This study aimed to investigate the preventive effects of green tea fractions (GTFs) on rat model of oxygen-induced retinopathy (OIR). Neonatal Sprague-Dawley rats were exposed to daily cycles of 80% oxygen (20.5 h), ambient air (0.5 h), and progressive return to 80% oxygen (3 h) until postnatal day 12 (P12), then the rats were placed in ambient air until P18. The green tea was fractionated by DM-A50, DM-W, M-B, and M-W. The rats were treated once daily from P6 to P17 by gastric gavage of GTFs (0.05 or 0.01 g/ml) or distilled water (DW) at 50 µl/10 g body weight. On P18, the rats were sacrificed and the retinal samples were collected. The retinal neovascularization (NV) was scored and avascular areas (AVAs) were measured as a % of total retinal area (%AVAs) in ADPase stained retinas. The NV scores in 0.01 g/ml M-W were significantly lower than those in DW. The %AVAs in 0.05 g/ml DM-A50 and in 0.05 g/ml and 0.01 g/ml M-W were significantly lower than those in DW. There were less catechins, and less caffeine in M-W fraction compared with other GTFs, suggesting components of green tea except for catechins and caffeine might suppress the neovascularization in rat model of OIR

Changes due to Aging in the Serum Biochemical Profile and Weights of Internal Organs Using the Rat as a Model

Rats were used as the experimental aging model. The rats were divided into four groups, aged 10,37,75 and 92 weeks. Serum biochemical data and organ weights were studied to determine the effects of aging. Serum protein in the older rats was unchanged when compared with the 10 week old rats, while serum albumin decreased. The A/G ratio decreased with aging. There was a sharp decrease in alkaline phosphatase at 37 weeks and activity remained low thereafter. Total serum cholesterol and phospholipids increased with aging. There was no variation in sodium and chlorine in this experiment.Liver and kidney weights in relation to body weight decreased with aging.Data variations in the biochemical profile may be caused not by increased synthesis but by a decrease in the catabolic rate

A Comparison of the Growth Rate of Rats on a Pellet Diet and a Semi Synthetic Diet

In the present study, the long-term effects of a pellet diet and a semi synthetic diet on the biochemical parameters of serum were investigated. After acclimation for one week, the 8 -week-old rats were divided into two groups and given either a pellet diet or a semi synthetic diet (20% casein diet). Blood was collected prior to and after 4 , 12,24 and 48 weeks on the diets. Body weights were higher in the semi synthetic diet group throughout their lifespan. The median survival rate of the semi synthetic diet group was 72 weeks, while that of the pellet diet group was 94 weeks. The serum AST concentration in the two groups was similar, though ALT was higher in the semi synthetic diet group. Total cholesterol in the serum increased in both groups but was higher in the semi synthetic diet group during the experimental period. The results obtained from this study suggest that the differences in the aging process in the rats fed the expeimental diets might related to cellulose and vitamins