The novel environment of a metabolic cage can be stressful for
rodents, but few studies have attempted to quantify this stressresponse. Therefore, we determined the effects on mean arterial
pressure (MAP) and heart rate (HR), of placing mice of both
sexes in metabolism cages for 2 days. After surgical implantation
of a carotid artery catheter mice recovered individually in
standard cages for 5 days. Mice then spent 2 days in metabolism
cages. MAP and HR were monitored in the standard cage on Day
5 and in metabolism cages on Days 6-7. MAP increased by 18±3
and 22±4 %, while HR increased by 27±4 and 27±6 %, in males
and females, respectively, during the first hours after cage
switch. MAP decreased to baseline in the fourth and eighth h
following metabolism cage switch in males and females,
respectively. However, HR remained significantly elevated in both
sexes during the entire two-day period in metabolism cages.
Females had lower MAP than males both pre- and postmetabolism cage switch, but there were no sex differences in HR.
These results demonstrate sustained changes in cardiovascular
function when mice are housed in metabolism cages, which could
potentially affect renal function.
Relation between mean arterial pressure and renal function in the early phase of shock: a prospective, explorative cohort study
