Rodlet cell distribution in the gall bladder epithelium of Fundulus heteroclitus

Rodlet cells within the epithelial mucosa of the gall bladder of the estuarine killifish Fundulus heteroclitus (L.) obtained from a highly contaminated creek adjacent to a landfill, were arranged within the constraints of the epithelium. Furthermore, the rodlet cells established a close intimate association with electron dense epithelioid cells. A comparison with fish from a non impacted estuary revealed a significantly greater number of rodlet cells in the 'contaminated' group. The abundance of rodlet cells within the gall bladder of the fish exposed to contaminants further strengthens the hypothesis that these cells participate in the fish's immune system.