Chloride extrusion in the isolated perfused teleost gill

Energy cost of NaCl transport in isolated gills of cutthroat trout

“…Second, there is a possibility that ouabain can have a vasosensitive effect on the branchial arteries, although the data are inconclusive. For example, Farmer and Evans (17) found that adding ouabain to the perfusate caused a marked vasoconstriction and increase in afferent pressure in isolated, perfused gills of the pinfish (Lagodon rhomboides), whereas Stagg and Shuttleworth (55) found that ouabain had only a slight effect on vascular resistance in perfused gills of the flounder. There were no noticeable effects of ouabain on afferent pressure in this study, although the flow rates were quite variable among preparations (coefficient of variation 44%).…”

Supraspinal and Reflex Control of Movement in Humans

“…However, the origin of this common synaptic input varied in the different pathologies. For subjects with XKS, the common synaptic input is probably cortical in origin (Mayston et al 1997), whereas for the remaining pathological mirror movement groups shared input to left and right homologous motoneurone pools due to branching of corticospinal axons has been inferred (Farmer et al 1990;Carr et al 1993;Harrison et al 1993). For those subjects with transient mirror movements associated with an acquired hemiplegia, no short duration central peaks were present in the crosscorrelogram, indicating that there are separate sources of synaptic drive that produce the bilateral EMG recorded during the unilateral task.…”

Fish Gill Ionic Transport: Methods and Models

“…Unfortunately, even vigorous stirring of the irrigation bath apparently does not mimic the irrigation patterns found in the intact animal, or the perfused head. For example, Shuttleworth and Freeman ( 1974) described Na + and Cl effluxes from the perfused eel (Anguilla dieffenbachii} gills that were only 10-15% of those found in the intact fish, and Farmer and Evans ( 1981 ) have recently found that the efflux of Cl~ from perfused pinfish (Lagodon rhomboides} gills is 45% that of the intact fish. Nevertheless, the perfused gill has provided us with some information unavailable with other techniques.…”

“…More recent studies have lent support for the "Silva model" for coupled Na + and Cl~ transport by the gill epithelium. Farmer and Evans (1981) have shown that the Cl efflux from the perfused pinfish gill is inhibited by removal of Na + from the perfusate, or addition of furosemide. Furosemide has been found to inhibit coupled Na + and Cl~ transport in a wide variety of epithelial tissues (Frizell et al, 1979).…”