Continuous intravenous infusion in the unrestrained rat — procedures and results

• Published in: Human & experimental toxicology 1995-02, Vol.14 (2), p.192-200
• Main Authors: Cave, Desmond A., Schoenmakers, Ankie C.M., van Wijk, Hans J., Enninga, Ilona C., van der Hoeven, Jan C.M.
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Blood Cells - drug effects; Blood Chemical Analysis; Body Weight - drug effects; Catheterization, Peripheral - methods; Catheters, Indwelling; Eating - drug effects; Female; Femoral Vein - drug effects; Femoral Vein - physiology; Femoral Vein - ultrastructure; General aspects. Methods; Infusions, Intravenous; Male; Medical sciences; Osmolar Concentration; Rats; Rats, Sprague-Dawley; Saline Solution, Hypertonic - administration & dosage; Saline Solution, Hypertonic - pharmacology; Specific Pathogen-Free Organisms; Toxicology; Urination - drug effects; Vena Cava, Inferior - drug effects; Vena Cava, Inferior - physiology; Vena Cava, Inferior - ultrastructure; Vena Cava, Superior - drug effects; Vena Cava, Superior - physiology; Vena Cava, Superior - ultrastructure
• ISSN: 0960-3271; 1477-0903
• DOI: 10.1177/096032719501400207

1 A method of continuous infusion in the unrestrained rat is described, which provides a scientifically accept able and easily maintained rodent model for use in toxicological investigations. 2 Sprague Dawley SPF rats had cannulas implanted into the vena cava via the femoral vein, and were continu ously infused with physiological saline for a total of 28 or 90 days. 3 The results indicate that there was no change in body weight, food consumption, clinical observations or clinical biochemistry of infused rats when compared to non-infused rats. There were small changes in haema tological parameters, however none were toxicological ly significant. Urinary volume was increased and uri nary specific gravity and osmolality were decreased. At macroscopic and microscopic examination there were findings of scar formation associated with the area of surgery and minimal irritation in the area of the vena cava which accommodated the cannula. 4 These results indicate that implantation of a cannula into the vena cava of a rat and subsequent continuous intravenous infusion of physiological saline produces no toxicological adverse effects over a period of 90 days. Consequently, this model can be recommended for the continuous intravenous administration of test substances to rats.