title: Preventive Role of Hilar Parasympathetic Ganglia on Pulmonary Artery Vasospasm in Subarachnoid Hemorrhage: An Experimental Study.
abstract: OBJECTIVE
  Pulmonary arteries are mainly innervated by sympathetic vasoconstrictor and parasympathetic vasodilatory fibers. We examined whether there is a relationship between the neuron densities of hilar parasympathetic ganglia and pulmonary vasospasm in subarachnoid hemorrhage (SAH).
  
  
  METHODS
  Twenty-four rabbits were divided into two groups: control (n=8) and SAH (n=16). The animals were observed for 20 days following experimental SAH. The number of hilar parasympathetic ganglia and their neuron densities were determined. Proportion of pulmonary artery ring surface to lumen surface values was accepted as vasospasm index (VSI). Neuron densities of the hilar ganglia and VSI values were compared statistically.
  
  
  RESULTS
  Animals in the SAH group experienced either mild (n=6) or severe (n=10) pulmonary artery vasospasm. In the control group, the mean VSI of pulmonary arteries was 0.777±0.048 and the hilar ganglion neuron density was estimated as 12.100±2.010/mm < sup > 3 < /sup > . In SAH animals with mild vasospasm, VSI=1.148±0.090 and neuron density was estimated as 10.110±1.430/mm < sup > 3 < /sup > ; in animals with severe vasospasm, VSI=1.500±0.120 and neuron density was estimated as 7.340±990/mm < sup > 3 < /sup > .
  
  
  CONCLUSIONS
  There was an inverse correlation between quantity and neuron density of hilar ganglia and vasospasm index value. The low numbers and low density of hilar parasympathetic ganglia may be responsible for the more severe artery vasospasm in SAH.
authors.affiliation: Ataturk University, School of Medicine, Department of Pulmonary Diseases, Erzurum, Turkey.
authors.forename: Omer
authors.initials: O
authors.lastname: Araz
authors.forename: Mehmet Dumlu
authors.initials: MD
authors.lastname: Aydin
authors.forename: Betul
authors.initials: B
authors.lastname: Gundogdu
authors.forename: Ender
authors.initials: E
authors.lastname: Altas
authors.forename: Murteza
authors.initials: M
authors.lastname: Cakir
authors.forename: Cagatay
authors.initials: C
authors.lastname: Calikoglu
authors.forename: Canan
authors.initials: C
authors.lastname: Atalay
authors.forename: Cemal
authors.initials: C
authors.lastname: Gundogdu
mesh_terms: D000818:Animals; D002452:Cell Count; D005726:Ganglia, Parasympathetic / Q000166:cytology / Q000473:pathology*; D006439:Hemodynamics; D053208:Kaplan-Meier Estimate; D008578:Meninges / Q000473:pathology; D009474:Neurons; D011651:Pulmonary Artery / Q000473:pathology*; D011817:Rabbits; D012129:Respiratory Function Tests; D013345:Subarachnoid Hemorrhage / Q000150:complications* / Q000473:pathology*; D016019:Survival Analysis; D020301:Vasospasm, Intracranial / Q000209:etiology* / Q000473:pathology*