Physiologische Bedeutung des Ammoniaks im Organismus der Wirbeltiere

The Metabolism of Trichinosed Rats During the Early Phase of the Disease

The changes in protein digestion, crude fibre digestion and the chief urinary constituents found in four rats after experimental infection with Trichinella spiralis are detailed.

Diarrhoea and anorexia occurred during the period 8 to 12 days after infection when protein digestion fell to its lowest point. It is suggested that this was due to antiproteases secreted by the adult parasites and to mechanical damage in the intestinal mucosa caused by their movements.

Urinary N rose immediately after infection in “non-resistant” rats. This was followed by a period of decreased N output after which the excretion rate rose steeply.

The urea output also rose immediately after infection in “non-resistant” rats. During the period 4 to 12 days from the time of infection urea excretion fell. Thereafter there was a great increase in its rate of output. Most of these changes have been attributed to toxins elaborated by the adult parasites for massive larval invasion of the tissues probably did not occur till after the experiments were terminated.

Ammonia excretion rose as urinary urea decreased. The fall in urea N was not compensated by the rise in ammonia N + the fall in dietary N intake. The ammonia output returned rapidly to normal suggesting that the excess ammonia was not produced in response to acidosis when the urea excretion rate rose.

Creatine excretion showed a marked fall during the period 4 to 12 days after infection. Urinary creatine and creatinine rose steeply following this period. Possible reasons for these variations are discussed.