Toxicological study of DTPA as a drug (V). Toxicities of Ca-DTPA, Ca-EDTA and CBMIDA after intravenous injection in beagle dogs.

Abstract

The toxicity of Ca-DTPA (calcium diethylenetriaminepentaacetic acid), Ca-EDTA (calcium ethylenediaminetetraacetic acid) and CBMIDA [Catechol-3, 6-bis (methyleiminodiacetic acid)] after intravenous injection were examined in beagle dogs. In the test (1), the change of serum total and ionic calcium levels following intravenous injection of each chelating agent was examined. The results showed that both total and ionic calium levels did not change at all by any of these chelating agents. In the test (2), each of these chelating agents (150μmol/kg) were intravenously injected to dogs daily for 1 month. No clinical untoward signs were observed in all groups. However, the significant decrease of mean body weights in Ca-DTPA groups was seen at 4 weeks after the beginning of injection. In a serum biochemical examination, the increases of GOT and GPT values in one dog, and BUN and creatinine values in another one were seen in Ca-DTPA group. No changes in all measured items were seen in Ca-EDTA group. The increases of GPT, ALP and creatinine values in one dog and GPT value in another one were observed in CBMIDA group. The slight congestion of mucosa in small intestine, the increase of lymphocytes in the lamina propria of small intestine and in the proximal tubles of kidney, and the degeneration of liver were observed in all groups. There were almost no differences in the degree of these histological changes in each group.