pockets of ROS?

Dear all,

recently, I stained my worms with a green dye H2DCFDA which detects ROS.

This dye is non-fluorescent when chemically reduced, but after cellular oxidation and removal of acetate groups by cellular esterases, it becomes fluorescent.

Many a times, I observed such images in the posterior end of the worm and also sometimes in the head - pockets of green signal or pockets of no signals. While the majority of worms show a continuous and uniform green staining throughout the head or the posterior end.

http://i56.photobucket.com/albums/g172/aiwei77/pockets.jpg

Would anyone have suggestions to explain such phenomenon? Are they linked to cellular compartments or syncytia?

I appreciate your kind help and look forward to your replies!

thanks!