Study of the effects of tissue reactions on the function of implanted glucose sensors.

The relationship between tissue reactions to a subcutaneously implanted glucose sensor and the function of the sensor was evaluated over a period of 4-weeks using tubular, porous polyvinyl alcohol (PVA) sponges implanted subcutaneously in rats. The PVA sponges were used as scaffolds in which the foreign body response could develop. Coil-type glucose sensors were then placed in the center of the PVA sponges and tested on day 3, and weekly thereafter.

Diffusion of [3H]dexamethasone in rat subcutaneous slices after injection measured by digital autoradiography.

A relatively simple method for the determination of the diffusion coefficient of a substance that has been injected into tissue is described. We illustrate this method using [3]dexamethasone injected into the subcutaneous tissue of rats. Digital autoradiography was used to measure the distribution of the [3H] dexamethasone within the subcutaneous tissue at 2.

Distribution of [3H]dexamethasone in rat subcutaneous tissue after delivery from osmotic pumps.

Inflammation surrounding implantable glucose sensors may be controlled through local release of dexamethasone at the site of implantation. In the present study, we evaluated the distribution of dexamethasone in rat subcutaneous tissue during the first 2.5 days after local release.