The effects of parabiosis on serum and kidney glycosidase activities in spontaneously diabetic mice.

Spontaneously diabetic non-obese mice of the ICR strain were newly inbred in Shionogi laboratory, Japan. Animals became diabetic suddenly, more frequently and severely in females. Blood glucose levels were 452 +/- 73 mg/100 ml with serum insulin levels of less than 1.0 microU/ml in the fed state. Parabiosis with normal control ICR mice for 2 weeks decreased the blood glucose level to 260 +/- 51 mg/100 ml (P less than 0.01) and resulted in serum insulin levels of 46.0 +/- 18.0 microU/ml (P less than 0.01). Kidney homogenate beta-N-acetylglucosaminidase and beta-galactosidase activities were reduced in diabetic mice (42% and 44% decreases respectively) (P less than 0.025 and P less than 0.001), and restored almost to normal after 2 weeks of parabiosis. Renal alpha-mannosidase activity was decreased 43% (P less than 0.001) in the diabetic mice but unaffected by parabiosis. Serum beta-N-acetylglucosaminidase, beta-galactosidase and alpha-glucosidase activities were significantly increased in diabetic mice (179%; 233% and 58% increase respectively) (P less than 0.005, P less than 0.001 and P less than 0.001), and returned to normal with parabiosis.