Effect of the polychlorinated biphenyl preparation, Aroclor 1242, on the quantity of neurosecretory material in the medulla terminalis X-organ of the fiddler crab, Uca pugilator.

Exposure of the fiddler crab, Uca pugilator, to the PCB preparation, Aroclor 1242, produces an increase in the quantity of neurosecretory material in the medulla terminalis X-organ. This Aroclor apparently inhibits release, but not synthesis, of one or more neurohormones.