Fenvalerate-induced alterations in circulatory thyroid hormones and calcium stores in rat brain

Differential Behavioral Responses of <I>Anopheles gambiae</I> (Diptera: Culicidae) Modulate Mortality Caused by Pyrethroid-Treated Bednets

“…Intraperitoneal administration of fenvalerate in male rats for 45 days at doses of 100 and 200 mg/kg bw/day (a dose level that also induced hyperexcitability, tremors and paralysis) induced significant increase in thyroid hormones' (T3 and T4) serum concentration (Kaul, 1996). However, a study conducted in rats treated for 21 days at a daily dose of 0.2 mg/rat 1 of a commercial formulation containing lambda-cyhalothrin at the concentration of 20% showed a reduction of T3 and T4 serum concentrations, with a concomitant increase of TSH serum levels (Akhtar et al, 1996).…”

Estrogenic Potential of Certain Pyrethroid Compounds in the MCF-7 Human Breast Carcinoma Cell Line

“…Using rat models, Kaul et al (13) showed fenvalerate to increase triiodothyronine (T3) and thyroxine (T4) levels in circulation inducing thyroid dysfunction (13). Aktar et al (14) found that ^-cyhalothrin and bifenthrin reduced serum levels of T3 and T4 in the rat, whereas only ^-cyhalothrin could decrease the T^/T3 ratio (14).…”

Fenvalerate Exposure Alters Thyroid Hormone Status in Selenium- and/or Iodine-Deficient Rats

“…The conclusion of the authors was that the effect of fenvalerate was through the inhibition of monodeiodination of T 4 , the principal pathway of T 3 generation. On the contrary, Kaul et al [29] observed significant increases in plasma T 4 and T 3 by treatment of fenvalerate (100 mg/kg, i.p., 45 days) in male Wistar rats. Wang et al [43] observed a dose-dependent decrease in T 4 and T 3 and elevation in TSH in permethrin-treated rats; however, with deltamethrin, the only alteration was the decrease of T 4 levels.…”

“…Available studies indicate that fenvalerate also causes alterations on thyroid hormone status. However, the results of these limited studies are controversial [29][30][31][32].…”