... conditions in their midgut with the underlying epithelial transport mechanisms being largely unknown. Using ion-selective microelectrodes, the present study demonstrated that pluteus larvae of the purple sea urchin have highly alkaline pH (pH ∼9) and low [Na + ] (∼120 mmol l −1 ) in their midgut fluids...

... of the gastric caecum ( Fig. 3 C,D). Fig. 3. Scanning ion-selective microelectrode technique (SIET) measurements of fourth instar A. aegypti larvae reared in freshwater or brackish water . (A) Representative example of in vivo H + transport along the surface of the gastric caecum of larvae reared...

... use the scanning ion-selective microelectrode technique to measure efflux and influx of K + , H + , Na + and Ca 2+ in intact worms. Transport of ions into, or out of, immobilized worms produces small gradients in ion concentration in the unstirred layer near the surface of the worm. These gradients...

...-mail: tripathi@tifr.res.in ) 16 3 2009 2009 stereology microperfusion H + V-ATPase carbonic anhydrase ion-selective microelectrodes SIET H + gradients surface pH The insect gut carries out some of the most vital functions of nutrition and solute and water balance...

... a number of physiological adaptations to the short-term and long-term stresses associated with blood feeding. More recent electrophysiological studies using voltage- and ion-selective microelectrodes have extended our understanding of the mechanisms and control of ion transport by the secretory...

...K. A. Collier; M. J. O’donnell ABSTRACT The pH and concentrations of K + and Cl − in the unstirred layer (USL) associated with the basolateral surfaces of the upper and lower Malpighian tubules of Rhodnius prolixus were measured using extracellular ion-selective microelectrodes. When stimulated...

... that would allow K + secreted into the goblet cavity to exit to the gut lumen, while preventing H + from exiting, remain unclear. © 1992 by Company of Biologists 1992 tobacco homworm Manduca sexta ion-selective microelectrodes active potassium transport intracellular pH intracellular...

...Andrew Barber; Gerrit Ten Bruggencate * Address for reprints: Abteilung Pharmakologie, E. Merck AG, Frankfurter Strasse 250, 6100 Darmstadt 1, West Germany. 20 3 1985 © 1985 by Company of Biologists 1985 Salivary glands acetylcholine ion-selective microelectrodes...