CHIRASHREE GH0SH, A.K. RAY, S. BHATTACHARYA AND SH. BHATTACHARYA
Abstract
Anabas testudineus were treated with non-lethal levels of metacid-50 (0.106 ppb) and carbaryl (1.66 ppm) for 90 days covering the pre-spawning and spawning phases of the annual reproductive cycle and also in spawning season, ovariectomized fish underwent a short-term (for 14 days) pesticidal (with metacid-50) exposure. The main purpose of the present work to observe the trend of alteration of sex steroids in the interrenal tissue due to the pesticidal contamination and also to investigate extra-ovarian source of sex steroids. Interrenal estradio1-17 b (E2) and progesterone (P) level significantly increased up to 15 days of exposure followed by a decline till the end of the experiment. In the ovariectomized experiment, we noticed after 14 days of pesticidal exposure, the plasma! P level of ovariectomized fish decreased sharply whereas, the P level in the interrenal tissue of the same group increased significantly in respect to the intact group of fish. The result shows clearly the occurrence of both sex steroids (E2 and P) in the interrenal tissue and the trend of alteration of the hormones was more or less similar to that in the ovarian tissue due to pesticidal contamination. So, interrenal steroidogenesis can also serve as an alternative model for toxicity bioassay.