With regard to the control of gill ion transport, recent
work suggests that crab branchial Na, K-ATPase
ESA may be controlled by a dopamine/cyclic AMP system
(16,32,33) and, possibly, by gill tissue concentrations of
polyamines (17). In contrast, Riestenpatt et al. (25) found
that cyclic AMP stimulates sodium uptake in split crab gill
lamellae by increasing apical sodium channel number and,
thus, apical sodium conductance.