Effect of D- and/or L-aspartic acids on feeding, drinking, urine outflow and core temperature.

Rats were given D- and/or L-aspartic acids (Asp) in saccharin solution for one week. Body weight gain, daily food and fluid intake, weight of faeces, urine outflow and osmolality, and rectal temperature were compared with those of the pretreatment period. After the rats had been sacrificed the weights of liver, spleen and kidney were estimated and compared with those of the control. The long-term oral administration of D-Asp caused a significant decrease in the weights of total body, liver and kidney, in the daily food and fluid intake, in the weight of faeces and in the volume of urine. The osmolality of urine of the rats administered D-Asp was significantly higher than that of the control. The concomitant oral administration of L-Asp seemed to antagonize the effects of D-Asp.