Details

Autor(en) / Beteiligte

• Lomniczi, A
• Mohn, C
• Faletti, A
• Franchi, A
• McCann, S. M
• Rettori, V
• Elverdin, J. C

Titel

Inhibition of salivary secretion by lipopolysaccharide: possible role of prostaglandins

Ist Teil von

• American journal of physiology: endocrinology and metabolism, 2001-08, Vol.281 (2), p.E405-E411

Ort / Verlag

United States

Erscheinungsjahr

2001

Quelle

MEDLINE

Beschreibungen/Notizen

• 1  Cátedra de Fisiología, Faculta de Odontología, Universidad de Buenos Aires, 1122; 2  Centro de Estudios Farmacológicos y Botánicos Consejo Nacional de Investigaciones Científicas y Técnicas, 1414 Buenos Aires, Argentina; and 3  Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, Louisiana 70808-4124 Inducible (calcium-independent) nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) are important in the regulation of the function of different organs during infection. A single dose of lipopolysaccharide (LPS; 5 mg/kg ip) within 6 h increased NOS activity (20%) and prostaglandin E (PGE) content (100%) in submandibular glands (SMG) and blocked stimulated salivary secretion in adult male rats. The administration of an iNOS synthesis inhibitor, aminoguanidine (AG), with LPS decreased NOS activity and PGE content. Furthermore, the administration of meloxicam (MLX), an inhibitor of COX-2, blocked the increase in PGE and the production of NO. The incubation of slices of SMG in the presence of 3-morpholinosydnonimine, a donor of NO, increased the release of PGE highly significantly. The incubation of SMG in the presence of a PGE 1 analog (alprostadil) increased the production of NO. These results indicate that LPS activates NOS, leading to NO release, which activates COX, generating PGEs that act back to further activate NOS, causing further generation of PGEs by activation of COX. Because the alprostadil administration inhibited stimulated salivation, LPS-induced inhibition of salivation appears to be caused by increased PGE production. Diminished salivary secretion produces poor oral health; thus the use of COX-2 inhibitors to counteract the effects of inhibited salivation should be considered. nitric oxide synthase; cyclooxygenase; noradrenaline; methacholine; endotoxemia