几种药物不同部位与不同途径给药对动物LD50的影响

盐酸普魯卡因与硫酸阿託品注射于小白鼠前肢腕部內側正中线深部时其LD₅₀值显著低于同一药物后肢肌內或背部皮下注射.氰化钾注射于小白鼠或大白鼠的上述部位其毒性显著低于后肢肌内注射与背部皮下注射.亚硝酸钠LD₅₀值于小白鼠中未見有上述的差别。实驗論証上述毒性差別主要不是因药物自注射部位吸收差別所致。盐酸普魯卡因不論肌內或腕內侧正中线深部注射都能有效地減低氰化鉀的毒性。大白鼠一側臂神經纵切除后一周,再注射氰化鉀于此側的腕內侧正中线深部,其毒性即显著低于正常动物同部位的給药組,故认为氰化鉀毒性的发生可能与神經机制有关。

THE EFFECT OF SITES AND ROUTES OF ADMINISTERATION OF SOME DRUGS ON ITS LD50IN ANIMALS

In mice when procaine hydrochloride and atropine sulphate were administered into the deep part of the wrist at median line (the so called "median wrist"), the LD₅₀ of these drugs were significantly lower than those when the drugs were injected intramuscularly into the hind legs or subcutaneously at the back. The toxicity of potassium cyanide for mice and rats by "median wrist" injection was significantly lower than that by intramuscular or subcutaneous injections. The cause of these differences was mainly not due to variable absorptions of the drugs from the injected sites. The effects of sites and routes of administeration on the toxicity of sodium nitrite were not statistically significant. The toxicity of potassium cyanide for rats by "median wrist" injection was lowered, if the brachial plexus of the injected side was resected a week earlier; this implies that the toxicity of the cyanide is related to the nervous functions. The results revealed that procaine hydrochloride given by "median wrist" injection was as effective as sodium nitrite by the same route in relieving potassium cyanide poisoning in mice, while procaine hydrochloride given by intramuscular injection was inferior to intramuscular injection of sodium nitrite.