Akhtar N, Kayani S A, Ahmad M M, Shahab M
Department of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan.
J Appl Toxicol. 1996 Sep-Oct;16(5):397-400. doi: 10.1002/(SICI)1099-1263(199609)16:5<397::AID-JAT362>3.0.CO;2-Y.
The present study was conducted to examine the effect of organochlorine (Heptachlor, Benzene hexachloride (BHC)), organophosphorus (Malathion, Monitor) and pyrethroid (Karate, Talstar) insecticides on the thyroid secretory function in rats. Heptachlor (0.5 mg per rat), BHC (0.66 mg per rat) Malathion (0.06 mg per rat), Monitor (0.2 mg per rat), Karate (0.2 mg per rat), Talstar (0.5 mg per rat) were orally administered to young adult rats for 21 days. Serum concentrations of triiodothyronine (T3), thyroxine (T4) and thyrotrophin (TSH) were determined by using specific radioimmunoassays. Body weight was not affected by treatment with any insecticide except Talstar (P < 0.01). Among organochlorine and organophosphorus insecticides, treatment with BHC and Malathion, respectively, led to a significant decrease (P < 0.01) in serum concentration of T3 and T4. Administration of BHC and Malathion also increased (P < 0.01) TSH secretion. Treatment with both of the pyrethroid insecticides similarly induced significant suppression (P < 0.01) of serum T3 and T4 levels, and concomitant stimulation (P < 0.01) of TSH concentrations. The T4/T3 ratio was decreased (P < 0.05) in rats treated with Karate but not with any other insecticide. These data indicate that immense care is warranted in the use of insecticides, because they not only affect the liver, kidney and other organs but also may alter the activity of the endocrine glands.
本研究旨在检测有机氯（七氯、六六六）、有机磷（马拉硫磷、久效磷）和拟除虫菊酯（功夫菊酯、高效氯氟氰菊酯）类杀虫剂对大鼠甲状腺分泌功能的影响。将七氯（每只大鼠0.5毫克）、六六六（每只大鼠0.66毫克）、马拉硫磷（每只大鼠0.06毫克）、久效磷（每只大鼠0.2毫克）、功夫菊酯（每只大鼠0.2毫克）、高效氯氟氰菊酯（每只大鼠0.5毫克）经口给予成年幼鼠，持续21天。采用特异性放射免疫分析法测定血清中三碘甲状腺原氨酸（T3）、甲状腺素（T4）和促甲状腺激素（TSH）的浓度。除高效氯氟氰菊酯外（P<0.01），体重不受任何杀虫剂处理的影响。在有机氯和有机磷杀虫剂中，六六六和马拉硫磷处理分别导致血清T3和T4浓度显著降低（P<0.01）。六六六和马拉硫磷的施用也增加了（P<0.01）TSH分泌。两种拟除虫菊酯类杀虫剂处理同样导致血清T3和T4水平显著降低（P<0.01），并伴随TSH浓度升高（P<0.01）。用功夫菊酯处理的大鼠T4/T3比值降低（P<0.05），但其他杀虫剂处理组未出现此现象。这些数据表明，使用杀虫剂时必须格外小心，因为它们不仅会影响肝脏、肾脏和其他器官，还可能改变内分泌腺的活性。
