Abstract
Background: Baroreceptor reflexes are regulated by nerve terminals of the glossopharyngeal and vagal nerves. The body of pressure-sensitive neurons of these nerves is located in the petrosal ganglion of both nerves. We examined whether there is a relationship between the neuron numbers of the inferior ganglion of the glossopharyngeal nerve and blood pressure values. Methods: Petrosal ganglions were examined in 18 male hybrid rabbits divided into three equal groups: Group A normotensive (TA=90-100 mmHg), Group B hypertensive (TA>100 mmHg); and Group C hypotensive (TA<90 mmHg). After examination of blood pressure for one week, all animals were sacrificed, and the petrosal ganglions extracted bilaterally and examined histopathologically using the physical dissector method. Results: The mean (±SD) neuronal density was: Group A 8700±200, Group B 7800±250 and Group C 9800±300, respectively. The difference between the groups B and C as compared to A was significant (p<0.01) while the difference between Groups B and C was highly significant (p<0.001). Conclusions: An inverse relationship was noticed between the neuronal density in the petrosal ganglion and blood pressure values with potential implications in the study of the etiology of hypertension.
Key words
Glossopharyngeal nerve - petrosal ganglion - neuron number - blood pressure
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Correspondence
Mehmet Dumlu AydinM.D., Associate Professor of Neurosurgery
Atatürk Universitesi Lojmanları
60. Blok, Kat:1, No: 3
Erzurum
Turkey
Phone: +90/532/322 83 89
Fax: +90/442/236 12 28
Email: nmda11@hotmail.com
