Spontaneous Tyzzer's disease in nude rats.

Pathophysiology of Spontaneous Hypercalciuria in Laboratory Rats

Recent data suggest a causal role of deranged 1,25(OH)2D metabolism in the syndrome of idiopathic hypercalciuria. To test this hypothesis, we evaluated if vitamin D availability and/or increased serum 1,25(OH)2D were critical for the expression of hypercalciuria in laboratory rats. Ca balance, serum 250HD3, and 1,25(0H)D3 were studied in D-deprived (-D) and D-repleted (+D) male progeny (p) born...

Renin in rats with spontaneous hypertension.

An age-dependent study of plasma renin activity (PRA), kidney renin activity (KRA), and plasma renin substrate was carried out in rats with spontaneous hypertension during the prehypertensive, the early hypertensive, and the established hypertensive phases of their disease. PRA and KRA were both significantly elevated before and during the initial phase of hypertension and normal or subnormal d...

Spontaneous Pressure Diuresis in Conscious Rats

Pressure diuresis is thought to be a long-term mechanism that is essential for regulation of blood volume and arterial pressure (AP). We recently found that experimentally-induced changes in AP result in changes in urine flow (UF) within 6 seconds in anesthetized rats. To test our hypothesis that the long-term nature of pressure diuresis is the result of the cumulative sum of many short-term ch...

Spontaneous convulsions in Charles River Wistar rats.

Spontaneous clonic convulsions in the Charles River Wistar rat have been observed at an incidence of 1.5%. Females (2.3%) are more susceptible than males (0.7%). These convulsions are not seen in rats of less than approximately 16 weeks of age. Some animals have exhibited single convulsions whilst others have convulsed on numerous occasions. No histopathological abnormalities of the brain have ...

Spontaneous Arteriosclerosis in Rabbits