Guanylate Cyclase Localization in Normal and Pathologic Human Dental Pulp

The Guanylate cyclase (GC) is an enzyme membrane activated by various primary messengers.It catalyzes the intracellular conversion of GTP in CMPc. Objectives:The aim of this work was to determine for the first time, the presence and GC activity in human dental pulp cells. Material and Methods:this study was made on 8 extracted dental pulps which were histopathologically classified (with Optical Microscopy on 2m sections, stained with methylene-blue and darkblue II 1:1) as it follows: 2 healthy, 3 in a initial serous acute pulpitis status, and 3 ones in advanced serous acute pulpitis status. One portion of specimens was incubated in basal medium, another portion in a basal medium + ANP(1nM) used as activator; another portion in basal medium + ANP (1nM)which has been inactivated after an incubation of 60min. at 20°C. The specimens were: 1) post-fixed in OSO4 at 1% cacodylate buffer for 45min. to 20°C.2) deydrated in increasing proportions of alcohol ethyl and immersed in a propylene oxide solution.3) included in Epon-Araldite.4) sectioned with thickness of 600-700A. 5)contrasted for 20 min. with uranile acetate alcohol at 50°C . 6)observed at the TEM to individuate the Pb which represent the GC activity. Results:In normal pulps GC Activity was highlighted in the no-odontoblastic cells, in the nervous and in the endothelial ones. GC Activity in pulps in an initial serous acute pulpits status was remarkably increased in no-odontoblastic cells, it was little increased in those nervous, it was normal in those endothelial. GC activity in Pulps in a terminal acute serious pulpits, was diminished in the no-odontoblastic cells, it was very increased in those nervous and endothelial. GC is present in dental pulp cells. Conclusions: Guanylate cyclase’s activity seems to change depending to the varying of healthy dental pulp or pathological state.