1H-NMR spectroscopy of urinary components of SHN mice in the course of spontaneous mammary tumourigenesis.

Proton nuclear magnetic resonance (1H-NMR) spectroscopy of urine was studied before and after the development of spontaneous mammary tumours in SHN mice. Urinary allantoin and lactic acid levels declined from 2 weeks before mammary tumour appearance and increased with the tumour growth after its appearance. The level of component at 3.4 ppm, which reacted with Ninhydrin and was possibly assigned to taurine, continued to decline beginning 2 weeks before tumour appearance. No considerable changes were observed in urinary levels of creatine and creatinine before and after tumour development, however, these components as well as allantoin or lactic acid had positive correlations with mammary tumour size. A negative correlation was observed between the level of 3.4 ppm component and tumour size. Surgical removal of tumours resulted in an apparent decline in urinary levels of allantoin and lactic acid. At all stages, urinary allantoin level was approximately 4 times as high as the levels of lactic acid and 3.4 ppm component. All results suggest that urinary allantoin would be a good indicator for the development of spontaneous mammary tumours of mice.