No study of pharmacokinetics, drug delivery, metabolism, or toxicity is complete without a determination of the drug concentration in blood. Blood sampling in small animals is necessarily limited by the volume of blood available. Sampling intervals of several hours are required to allow the subject to replenish fluids. Sampling frequency is therefore a primary advantage of vascular microdialysis. Since no blood or fluid is removed, the subject remains hydrated and the collected samples are more representative of a normal state.
IV Vascular Microdialysis Probes were designed for implantation into the rat jugular vein. They are also suitable for other soft tissues. Each probe includes a syringe needle and temporary cannula (split introducer) which aid placement. The thin-walled, plastic introducer slides over the syringe needle, which is then used to pierce the vein. The needle is removed and replaced with an IV Probe. A flexible wire mesh on the probe is sutured to the pectoral muscle. The cannula is then pulled out of the vein, leaving the probe behind. Inlet and outlet lines to the probe are housed within a single piece of flexible tubing, which is externalized by use of a surgical introducer needle.
The flexible probe, web, and connecting tube improve the comfort of a freely moving animal. The small OD of the probe is less likely to occlude the blood vessel.