Impairment of the regulation of gonadal function in Channa punctatus by metacid-50 and carbaryl under laboratory and field conditions.
Regulation of gonadal function by gonadotropic hormone (GtH) and gonadotropin-releasing hormone (GnRH) in Channa punctatus was significantly affected by nonlethal levels of Metacid-50 and Carbaryl. Under laboratory conditions, the time-dependent decrease in serum GtH level was higher in Carbaryl-treated fish than in Metacid-50-treated fish. The situation was reversed in the field, with a higher inhibitory effect of Metacid-50 being recorded. On the other hand, pituitary GtH content and GnRH activity were inhibited to a greater extent by Metacid-50 than by Carbaryl under both field and laboratory conditions. The present findings highlight that even low doses of Metacid-50 and Carbaryl are effective enough to cause reproductive damage, as evidenced by homeostatic unbalance of the reproductive regulatory system.
Ghosh
P
P
Environmental Toxicology Laboratory, Visva-Bharati University, Santiniketan, India.
Bhattacharya
S
S
Bhattacharya
S
S
D000818:Animals; D012721:Carbaryl / Q000032:analysis / Q000633:toxicity*; D005399:Fishes; D006065:Gonadotropins, Pituitary / Q000097:blood*; D006066:Gonads / Q000187:drug effects*; D008743:Methyl Parathion / Q000032:analysis / Q000633:toxicity*; D010278:Parathion / Q000031:analogs & derivatives*; D010902:Pituitary Gland / Q000032:analysis / Q000187:drug effects*; D010906:Pituitary Hormone-Releasing Hormones / Q000097:blood; D011863:Radioimmunoassay; D014873:Water Pollutants / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
D006065:Gonadotropins, Pituitary; D010906:Pituitary Hormone-Releasing Hormones; D014873:Water Pollutants; D014874:Water Pollutants, Chemical; D008743:Methyl Parathion; D010278:Parathion; D012721:Carbaryl