Nitric oxide synthase in healthy and inflamed human dental pulp.
Nitric oxide synthase (NOS) plays a significant role in the pathogenesis of pulpitis. In this study, we hypothesized the existence of endothelial (eNOS) and inducible (iNOS) enzyme isoforms in human dental pulp. Extracted third molar pulps were divided into groups based on clinical diagnosis: healthy, hyperemic, and irreversible pulpitis. We have localized the eNOS and iNOS by immunohistochemistry and have tested their mRNA expression by RT-PCR and protein levels by Western blots. eNOS is present in the endothelial cells and odontoblasts of the healthy pulp, but an elevation of eNOS mRNA and protein levels with a concomitant dilation of vessels was characteristic under pathological conditions. Healthy pulp tissue failed to exhibit any iNOS; however, acute inflammation enhanced the mRNA and protein levels of iNOS, mainly in the leukocytes. There are differences in localization and expression between eNOS and iNOS in healthy and inflamed dental pulp.
Di Nardo Di Maio
F
F
Institute of Human Physiology and Clinical Experimental Research, Semmelweis University, Budapest, Hungary.
Lohinai
Z
Z
D'Arcangelo
C
C
De Fazio
P Esposito
PE
Speranza
L
L
De Lutiis
M A
MA
Patruno
A
A
Grilli
A
A
Felaco
M
M
D000328:Adult; D003782:Dental Pulp / Q000166:cytology / Q000201:enzymology* / Q000473:pathology; D042783:Endothelial Cells / Q000201:enzymology / Q000473:pathology; D006801:Humans; D006940:Hyperemia / Q000201:enzymology* / Q000473:pathology; D007091:Image Processing, Computer-Assisted; D066298:In Vitro Techniques; D007249:Inflammation / Q000201:enzymology; D007527:Isoenzymes / Q000378:metabolism; D008964:Molar, Third / Q000201:enzymology / Q000473:pathology; D019001:Nitric Oxide Synthase / Q000235:genetics / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D009804:Odontoblasts / Q000201:enzymology / Q000473:pathology; D011671:Pulpitis / Q000201:enzymology* / Q000473:pathology; D012333:RNA, Messenger / Q000032:analysis; D012016:Reference Values; D014664:Vasodilation / Q000502:physiology
D007527:Isoenzymes; D012333:RNA, Messenger; C496319:NOS2 protein, human; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III