Proline transport and oxidation in short-circuited locust rectum: effect of cAMP
- 1 September 1984
- journal article
- research article
- Published by Canadian Science Publishing in Canadian Journal of Zoology
- Vol. 62 (9) , 1732-1736
- https://doi.org/10.1139/z84-254
Abstract
Proline absorption from the lumen is the main source of substrate supporting electrogenic Cl− transport and short-circuit current (Isc) in locust rectum. Since cAMP stimulates chloride-dependent Isc by up to 10-fold, we investigated whether this stimulant also increases active transport of the major metabolic substrate proline. A large 40:1 flux ratio of [14C]proline under short-circuited conditions confirmed that net absorption of this amino acid is by active transport. Unexpectedly, cAMP caused a 40% decrease in net transepithelial flux of proline. A 45% increase in the amount of proline oxidized to 14CO2 could account for only 10% of this decrease in proline flux, suggesting that increased Cl− transport after stimulation may competitively reduce the energy supply for proline transport.This publication has 0 references indexed in Scilit: