title: Parasympathetic innervation of the meibomian glands in rats.
abstract: OBJECTIVE
  To determine the location of parasympathetic neurons that innervate the meibomian glands in rats.
  
  
  METHODS
  The B subunit of cholera toxin (CTB), fast blue, and a retrograde transneuronal tracer, the Bartha strain of pseudorabies virus (PRV-Ba), were injected into the upper eyelids of adult Sprague-Dawley rats after sectioning the ipsilateral branches of the facial nerve and resecting the superior cervical ganglia. Brains and orbital tissues were processed for the immunohistochemical detection of PRV-Ba and CTB. In selected cases, series of brain sections were double labeled for PRV-Ba and tyrosine hydroxylase to determine the relationship between the A5 noradrenergic cell group and superior salivatory nucleus, or for PRV-Ba and choline acetyltransferase to establish the neurochemical phenotype of parasympathetic preganglionic neurons.
  
  
  RESULTS
  Labeled ganglionic cells were diffusely distributed within the ipsilateral pterygopalatine ganglion (PPG) and along the more proximal portions of the greater petrosal nerve (GPN). Labeled preganglionic neurons were cholinergic and were located immediately dorsolateral to the rostral-most portion of the facial nucleus and caudal superior olive, where they intermingled with A5 noradrenergic cells.
  
  
  CONCLUSIONS
  The meibomian glands and other structures within the lid margin are subject to parasympathetic regulation by ganglion cells diffusely distributed within the PPG and along more proximal portions of the GPN. Cholinergic parasympathetic preganglionic neurons that project to meibomian gland-innervating ganglion cells are located immediately lateral, dorsal, and rostral to the facial motor nucleus in the region commonly referred to as the superior salivatory nucleus.
authors.affiliation: Department of Neurology, University of Tennessee Health Science Center, Memphis, TN 38163, USA. mledoux@utmem.edu
authors.forename: M S
authors.initials: MS
authors.lastname: LeDoux
authors.forename: Q
authors.initials: Q
authors.lastname: Zhou
authors.forename: R B
authors.initials: RB
authors.lastname: Murphy
authors.forename: M L
authors.initials: ML
authors.lastname: Greene
authors.forename: P
authors.initials: P
authors.lastname: Ryan
mesh_terms: D000578:Amidines; D000818:Animals; D002772:Cholera Toxin / Q000032:analysis; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D011558:Herpesvirus 1, Suid / Q000502:physiology; D007150:Immunohistochemistry; D008537:Meibomian Glands / Q000294:innervation*; D010275:Parasympathetic Nervous System / Q000033:anatomy & histology* / Q000201:enzymology / Q000821:virology; D051381:Rats; D017207:Rats, Sprague-Dawley; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
chemical_list: D000578:Amidines; C031455:diamidino compound 253-50; D002772:Cholera Toxin; D014446:Tyrosine 3-Monooxygenase; D002795:Choline O-Acetyltransferase