TY - JOUR
T1 - Bilateral reflex vasodilation in the palatal mucosa evoked by unilateral tooth-pulp stimulation in the cat
AU - Shoji, N.
N1 - Copyright:
This record is sourced from MEDLINE/PubMed, a database of the U.S. National Library of Medicine
PY - 1996
Y1 - 1996
N2 - In a previous study in cats, we found that electrical stimulation of the tooth pulp caused blood flow increases at various sites in the ipsilateral oral mucosa (upper and lower gingivae, lower lip, buccal mucosa and tongue, and, notably, bilaterally in the palatal mucosa). Tooth-pulp stimulation is well-known to induce severe pain and to evoke autonomic reflex responses in other organs and tissues. The purpose of this study was: to confirm that tooth-pulp stimulation may indeed induce autonomically mediated vasodilator responses in the feline oral mucosa away from the stimulated tooth, and to test our hypothesis that the reflex pathway involves parasympathetic vasodilator fibers as efferents. Dynamic changes in palatal mucosal blood flow (PMBF), with lower lip blood flow (LBF) as a control, were investigated in anesthetized, cervically sympathectomized cats by means of Laser Doppler Flowmetry. Unilateral electrical stimulation of the maxillary canine tooth pulp produced hexamethonium-sensitive bilateral increases in PMBF in a stimulus-intensity-dependent manner, without an increase in systemic blood pressure; LBF increased only ipsilaterally. Bilateral section of the glossopharyngeal nerve roots had no effect on the vasodilator responses, while unilateral section of the facial nerve root or lesion of the pterygopalatine ganglion (PPG) abolished the response on that side. Intracranial electrical stimulation of the peripheral cut ends of the facial or glossopharyngeal nerve roots caused an increase in ipsilateral PMBF. These results indicate that unilateral tooth-pulp stimulation induces a bilateral reflex vasodilator response in the palatal mucosa mediated viaparasympathetic vasodilator fibers that emerge from the brain stem with the facial nerve and reach the blood vessels viaPPG. Although there is a dual innervation of the cat palatal mucosa by parasympathetic vasodilator fibers running viathe facial and glossopharyngeal nerve roots, the latter are not involved in the bilateral reflex responses.
AB - In a previous study in cats, we found that electrical stimulation of the tooth pulp caused blood flow increases at various sites in the ipsilateral oral mucosa (upper and lower gingivae, lower lip, buccal mucosa and tongue, and, notably, bilaterally in the palatal mucosa). Tooth-pulp stimulation is well-known to induce severe pain and to evoke autonomic reflex responses in other organs and tissues. The purpose of this study was: to confirm that tooth-pulp stimulation may indeed induce autonomically mediated vasodilator responses in the feline oral mucosa away from the stimulated tooth, and to test our hypothesis that the reflex pathway involves parasympathetic vasodilator fibers as efferents. Dynamic changes in palatal mucosal blood flow (PMBF), with lower lip blood flow (LBF) as a control, were investigated in anesthetized, cervically sympathectomized cats by means of Laser Doppler Flowmetry. Unilateral electrical stimulation of the maxillary canine tooth pulp produced hexamethonium-sensitive bilateral increases in PMBF in a stimulus-intensity-dependent manner, without an increase in systemic blood pressure; LBF increased only ipsilaterally. Bilateral section of the glossopharyngeal nerve roots had no effect on the vasodilator responses, while unilateral section of the facial nerve root or lesion of the pterygopalatine ganglion (PPG) abolished the response on that side. Intracranial electrical stimulation of the peripheral cut ends of the facial or glossopharyngeal nerve roots caused an increase in ipsilateral PMBF. These results indicate that unilateral tooth-pulp stimulation induces a bilateral reflex vasodilator response in the palatal mucosa mediated viaparasympathetic vasodilator fibers that emerge from the brain stem with the facial nerve and reach the blood vessels viaPPG. Although there is a dual innervation of the cat palatal mucosa by parasympathetic vasodilator fibers running viathe facial and glossopharyngeal nerve roots, the latter are not involved in the bilateral reflex responses.
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U2 - 10.1177/00220345960750090401
DO - 10.1177/00220345960750090401
M3 - Article
C2 - 8952615
AN - SCOPUS:0030307292
VL - 75
SP - 1637
EP - 1643
JO - Journal of Dental Research
JF - Journal of Dental Research
SN - 0022-0345
IS - 9
ER -