title: Long-term measurement of arterial blood pressure in conscious mice.
abstract: This study describes a technique for the direct daily measurement of arterial blood pressure, sampling of arterial blood, and continuous intravenous infusion in free-moving, conscious, Swiss-Webster mice. Catheters were chronically implanted in the femoral artery and vein, tunneled subcutaneously, exteriorized at the back of the neck in a lightweight tethering spring, and attached to a swivel device at the top of the cage. Time-control experiments (n = 8) demonstrated stable values of mean arterial pressure (MAP, 116 +/- 1 mmHg) and heart rate (HR, 627 +/- 21 beats/min) for up to 35 days after catheter implantation. It was further observed that restraining mice (n = 7) increased MAP by 10 +/- 3 mmHg and HR by 78 +/- 8 beats/min from the values observed under free-moving conditions. To demonstrate the chronic use of the venous catheter, intravenous infusion of NG-nitro-L-arginine methyl ester (L-NAME, 8.6 mg.kg-1.day-1, n = 6) for 5 days significantly increased MAP from 117 +/- 4 to 131 +/- 4 mmHg without altering HR. In a final group of mice (n = 5), oral L-arginine (2% in drinking water) increased plasma arginine concentration from 90 +/- 7 to 131 +/- 17 microM and prevented L-NAME hypertension. These experiments illustrate the feasibility of long-term intravenous infusion, direct arterial blood pressure measurements, and arterial blood sampling in conscious mice.
authors.affiliation: Department of Physiology, Medical College of Wisconsin, Milwaukee 53226, USA.
authors.forename: D L
authors.initials: DL
authors.lastname: Mattson
mesh_terms: D000818:Animals; D001120:Arginine / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology; D001158:Arteries; D001794:Blood Pressure / Q000187:drug effects; D001795:Blood Pressure Determination / Q000379:methods*; D001800:Blood Specimen Collection / Q000379:methods; D002408:Catheters, Indwelling; D004326:Drinking / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000494:pharmacology; D006339:Heart Rate; D007262:Infusions, Intravenous; D051379:Mice; D019331:NG-Nitroarginine Methyl Ester / Q000008:administration & dosage / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors
chemical_list: D004791:Enzyme Inhibitors; D001120:Arginine; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester