[Evaluation of an in vivo perfusion technic for the dental pulp in rats as validated by demonstration of the release of prostaglandins].
Many different biologically active substances contribute to the metabolism of dental pulp. Until now, release of these substances has been evaluated only by in vitro studies. The aim of this study was to establish a technique of perfusion allowing the evaluation in vivo of the secreting activity of dental pulp. In order to validate this technique, the in vivo release of prostaglandins, substances which seem to play a key role in pulpal metabolism was measured. The "push-pull" perfusion technique was used, whereby a physiological medium was made to bath the pulpal surface by aspiration. Pulp was exposed by opening an upper incisor in an anaesthetized rat. The perfusion was kept constant by means of a device composed of cannula, catheters, and micropumps which produced a flow followed by an aspiration of the liquid. Every ten minute fraction was analysed by high performance liquid chromatography. Ten minutes after the beginning of perfusion, the results showed a kinetic for PGE2 and PGF2 alpha release, characterized by a base level of 7.4 +/- 6.7 and 28.6 +/- 12.0 pg/min respectively. These were interrupted by a very high peak as compared to base level (19 times higher for PGE2 and 6.6 times for PGF2 alpha), occurring fifty minutes after trepanation. This experiment is the first attempt made in vivo and in situ, to measure biologically active substances of pulpal origin.
D000818:Animals; D002404:Catheterization / Q000295:instrumentation; D002851:Chromatography, High Pressure Liquid; D003782:Dental Pulp / Q000378:metabolism*; D015237:Dinoprost; D015232:Dinoprostone; D007260:Infusion Pumps; D008297:Male; D010477:Perfusion / Q000295:instrumentation / Q000379:methods*; D011458:Prostaglandins E / Q000493:pharmacokinetics*; D011460:Prostaglandins F / Q000493:pharmacokinetics*; D051381:Rats; D011919:Rats, Inbred Strains
D011458:Prostaglandins E; D011460:Prostaglandins F; D015237:Dinoprost; D015232:Dinoprostone
Mise au point d'une technique de perfusion in vivo de la pulpe dentaire de rat validée par la mise en évidence de la libération de prostaglandines.