Changes in Growth Hormone and Cortisol Profile due to Lead Induced Toxicity in Labeo rohita

Özet

The present study was conducted to investigate the effect of lead (Pb) on the growth hormone (GH) and plasma cortisollevel of common carp, Labeo rohita. One hundred Labeo rohita were divided in two equal groups; control and treated.Treated fishes were exposed to 1.4mg/l of lead acetate (1.9% lead concentration i,e., LC50) at the interval of 72 hours for aperiod of five weeks. Blood was collected from the caudal vein of fish from both treated and control groups, after weekinterval. Mean body weight of treated group decreased significantly as compared to the control group (P<0.001) on weeklybasis. GH decreased significantly (P<0.001) in the treated group from first week to the last week of the treatment as comparedto the control group. In treated groups, the plasma cortisol level increased gradually from week 1 to week 5. Significantnegative correlation between GH concentration and cortisol level (Pearson r=-0.94) was observed. It is concluded that Pb actsas endocrine disrupter in fish bodies by altering the pattern of synthesis and metabolism of cortisol as well as GH. Elevation inbasal cortisol level markedly influences the growth rate by decreasing the GH ultimately decreasing body weight of animal.