Effect of neem oil on the adenohypophysis of Glossogobius giuris
The adenohypophysis of the fish G. giuris histopathology was observed during post spawning phase, on treatment with sub lethal concentrations of Neem oil (0.05 ppm, 0.25 ppm and 0.5 ppm) for 24, 48, 72 and 96 hrs intervals. The results of the present study showed PRL cells were spherical or ovoid, the nuclei were found beneath the nuclear membrane. Cells were partially granular. The RPD of the pituitary PRL cells became small and their nuclei were frequently pycnotic with diffused chromatin material. GTH cells were completely vacuolated and appeared oval or spherical in shape. The fishes at higher concentration of neem oil showed signs of degranulation and vacuolization. Intercellular spaces became conspicuous. The nuclear diameter decreases, cells were small and densely granulated cytoplasm. Most of the cells in the RPD undergone degranulation. GTH cells became totally degranulated, appearance of vacuolization, large intercellular spaces were observed due to coalition of small vacuoles. The various stages of degranulation which were distributed sparsely. A reduction in the number and diameter of the gonadotrophs indicate possible reduction in release of gonadotroph hormone.