GLP-1 hormone linked to dehydration in diabetes

Some drugs that are used to treat diabetes have been found to mimic the behaviour of a hormone that controls fluid intake, raising concerns of dehydration.
GLP-1 hormone
The GLP-1 hormone increases the release of insulin in the body, which functions in the same way as many injectable treatments for diabetes.
However, a paper from psychologist Derek Daniels of the University at Buffalo has cited a notable absence in research on the hormone’s role in fluid intake.
Daniels reports that when GLP-1 binds to receptors in the body, a signal is sent to the brain to decrease the intake of fluid.
“We blocked that signalling,” said Naomi J. McKay, a graduate student and co-author of the paper. “In doing so, we found an elevation in water intake.”
Licking patterns
This blocking became harder when measuring increases in a rat’s fluid intake after consuming the GLP-1 hormone, as they consume fluid in nanolitres. With nearly five million nanolitres required to fill a teaspoo, researchers used a lickometer to study licking patterns.
Lickometers measure the number of times a rat’s tongues touches an electrical point, with the number of licks monitored and translated to provide a given fluid volume.
“Licking patterns can give us hints about why rats drink more or less after an experimental manipulatio,” said Daniels. “In this study, we found that the rats were probably drinking more because they were feeling less full from the drinking.
“Clearly what we’re seeing, is that these substances decrease drinking behaviour,” said Daniels. “But we’re not saying people shouldn’t use these drugs to treat diabetes, and we’re not saying they are ineffective tools for the treatment of diabetes.
“However for populations already at risk for dehydration it may be something we want to be more concerned about.”