Abstract
Some properties of canine alkaline phosphatase (ALP) from the sera of normal adult and puppy and from the tissues such as intestine, liver, bone and kidney were examined and compared with those of the serum ALP from several disease model dogs. The serum ALP of a 1-month old puppy was 4.7 times higher than that of adult. The pH optimum of intestinal ALP was 9.9, and that of both the other tissues and normal sera was 10.1. Intestinal ALP was stable for heat, but the other ALP were inactivated by more than half in a 20 min incubation at 56°C. The order of heat stability was intestine>>kidney>liver=adult serum>bone=puppy serum. L-phenylalanine (LPA) inhibited intestinal ALP more than the others, and imidazole (IMI) inhibited the others more than intestine. Slight difference in IMI inhibition on the ALP activity between adult and puppy serum seems to correspond to the difference of the isozyme from liver and bone. Electrophoresis. using cellogel separated each ALP isozyme. The serum ALP from the disease models of bile duct obstruction and hyperadrenocorticism was more stable for heat than normal serum ALP, but the serum ALP from the disease model of hepatic disorder was not different from that from normal dog. The serum ALP from the disease model of hyperadrenocorticism was clearly distinguished from the other serum ALP by the effect of IMI and by the electrophoregram. Not only the activity but also some of these properties might be useful as the tool for clinical examination.
