Localization of smooth-muscle myosin in branchial pillar cells of snapper (Chrysophys auratus) by immunofluorescence histochemistry.

Smooth muscle myosin was localized in pillar cells by immunofluorescence histochemistry of gills from snapper (Chrysophys auratus). The amount of myosin present is comparable to that seen in mammalian vascular smooth muscle. No differences in the distribution of myosin-containing pillar cells, either within or between different secondary lamellae, were noted. The possibility that contractile proteins in pillar cells could function as autoregulators of blood flow, by responding with changes in active tension to alterations in the rate of change of pressure with each cardiac cycle, is discussed.