Open AccessTransient hypertension and sustained tachycardia in mice housed individually in metabolism cages
Author(s) -
Chantal Hoppe,
Karen M. Moritz,
S Fitzgerald,
John F. Bertram,
Roger G. Evans
Publication year - 2009
Publication title -
physiological research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.647
H-Index - 70
eISSN - 1802-9973
pISSN - 0862-8408
DOI - 10.33549/physiolres.931390
Subject(s) - cage , metabolism , medicine , endocrinology , tachycardia , mean arterial pressure , zoology , blood pressure , heart rate , biology , mathematics , combinatorics
The novel environment of a metabolic cage can be stressful forrodents, but few studies have attempted to quantify this stressresponse. Therefore, we determined the effects on mean arterialpressure (MAP) and heart rate (HR), of placing mice of bothsexes in metabolism cages for 2 days. After surgical implantationof a carotid artery catheter mice recovered individually instandard cages for 5 days. Mice then spent 2 days in metabolismcages. MAP and HR were monitored in the standard cage on Day5 and in metabolism cages on Days 6-7. MAP increased by 18±3and 22±4 %, while HR increased by 27±4 and 27±6 %, in malesand females, respectively, during the first hours after cageswitch. MAP decreased to baseline in the fourth and eighth hfollowing metabolism cage switch in males and females,respectively. However, HR remained significantly elevated in bothsexes 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 cardiovascularfunction when mice are housed in metabolism cages, which couldpotentially affect renal function.