title: [Effect of proximate environment on drug susceptibility of mice (author's transl)].
abstract: The present study was performed in order to elucidate the effect of proximate environment on drug susceptibility of mice. Three experiments were carried out independently. In the first experiment, mongrel and ddS mice produced under an unsatisfactory control of proximate environment were purchased, and acute toxicity tests of thiamine hydrochloride (B1HCl) and isonicotinic acid hydrazide (INAH) were practiced at two different conditioned rooms. In the second experiment, ddY mice produced under the conventional environment controlled to a certain extent were purchased, and the toxic effect of B1HCl was examined under the similar environment. In the third experiment, the sensitivity to B1HCl of RFVL mice produced under the strict barrier system was tested at the severe air-conditioned room. LD50 and their fLD50 values were calculated by Litchfield-Wilcoxon's method, and the variance analyses were carried out. The severer the environmental control after the purchase of mice turned to the higher the drug sensitivity. This respect was more remarkable in INAH of which the toxic response is appeared slowly compared with B1HCl. Furthermore, seasonal variation was found in LD50 values. However, seasonal effect differed from rearing and experimental conditions. In the third experiment which these proximate environments were controlled severely, seasonal variation was very small. From the results of these experiments, it was defined that the use of animals produced under the satisfactory rearing condition and severe environmental control are necessary for animal experiments.
mesh_terms: D000389:Air Conditioning; D000818:Animals; D004361:Drug Tolerance; D004780:Environment, Controlled; D005260:Female; D006361:Heating; D007538:Isoniazid / Q000633:toxicity; D007928:Lethal Dose 50; D008297:Male; D051379:Mice / Q000502:physiology*; D012621:Seasons; D013831:Thiamine / Q000633:toxicity; D014116:Toxicology
chemical_list: D007538:Isoniazid; D013831:Thiamine