Korean J Physiol Pharmacol.  1997 Dec;1(6):809-816.

Role of endogenous nitric oxide in the control salivary secretion and blood flow

• Kim W
• Nam SC
• Kim M

Abstract

The present study was designed to investigate whether endogenous nitric oxide (EDNO) is involved in submandibular vasodilation and salivation induced by parasympathetic nerve stimulation. Effects of Nw-nitro-L-arginine-methyl ester (L-NAME) which blocks the synthesis of EDNO from L-arginine on the submandibular vasodilation and salivation induced by chorda stimulation or administration of various vasodilators were examined in anesthetized cats. Effect of L-NAME on K+ efflux induced by carbachol was also examined using the excised submandibular slice in vitro. In the submandibular slices, acetylcholine (10(-5) mol/L) or vasoactive intestinal polypeptide (VIP, 10(-5) mol/L) increased NO2 contents, which was prevented by pretreatment with L-NAME. Salivary secretion in response to the chorda stimulation (3 V, 1 msec, 10 ~ 20 Hz) was completely blocked by treatment with atropine (1 mg/kg). Increased blood flow response to the low frequency (1, 2, 5 Hz) stimulation was significantly reduced, whereas the blood flow induced by the higher frequency (10, 20 Hz) stimulation was not affected. Lingual-arterial infusion of L-NAME (100 mg/kg) significantly diminished the vasodilatory and salivary responses to the chorda stimulation at all stimuli frequencies used. Intra-arterial infusion of L-NAME (100 mg/kg) markedly diminished the vasodilatory responses to acetylcholine (5 mug/kg), VIP (5 mug/kg) or bradykinin (5 mug/kg). In the excised submandibular slice, K+ efflux in response to carbachol (10(-5) mol/L) was significantly decrease by pretreatment with L-NAME (10(-5) mol/L). In the isolated submandibular artery precontracted with phenylephrine (10(-5) mol/L), the vasorelaxation induced by ACh (10-7 mol/L) was reversed into a contraction by methylene blue (10(-4) mol/L). These results suggest that EDNO may play an important role in vasodilation and secretion of the submandibular gland.

Keyword

Endogenous nitric oxide; Salivary gland; L-NAME; Blood flow; Salivation

MeSH Terms

Acetylcholine
Animals
Arginine
Arteries
Atropine
Bradykinin
Carbachol
Cats
Infusions, Intra-Arterial
Methylene Blue
NG-Nitroarginine Methyl Ester
Nitric Oxide*
Phenylephrine
Salivary Glands
Salivation
Submandibular Gland
Vasoactive Intestinal Peptide
Vasodilation
Vasodilator Agents
Acetylcholine
Arginine
Atropine
Bradykinin
Carbachol
Methylene Blue
NG-Nitroarginine Methyl Ester
Nitric Oxide
Phenylephrine
Vasoactive Intestinal Peptide
Vasodilator Agents