Distribution of P2X(3) receptor immunoreactivity in myenteric ganglia of the mouse esophagus.
Intraganglionic laminar endings (IGLEs) represent the major vagal afferent terminals throughout the gut. Electrophysiological experiments revealed a modulatory role of ATP in the IGLE-mechanotransduction process and the P2X(2)-receptor has been described in IGLEs of mouse, rat and guinea pig. Another purinoceptor, the P2X(3)-receptor, was found in IGLEs of the rat esophagus. These findings prompted us to investigate occurrence and distribution of the P2X(3)-receptor in the mouse esophagus. Using multichannel immunofluorescence and confocal microscopy, P2X(3)-immunoreactivity (-iry) was found colocalized with the vesicular glutamate transporter 2 (VGLUT2), a specific marker for IGLEs, on average in three-fourths of esophageal IGLEs. The distribution of P2X(3) immunoreactive (-ir) IGLEs was similar to that of P2X(2)-iry and showed increasing numbers towards the abdominal esophagus. P2X(3)/P2X(2)-colocalization within IGLEs suggested the occurrence of heteromeric P2X(2/3) receptors. In contrast to the rat, where only a few P2X(3)-ir perikarya were described, P2X(3) stained perikarya in ~80% of myenteric ganglia in the mouse. Detailed analysis revealed P2X(3)-iry in subpopulations of nitrergic (nNOS) and cholinergic (ChAT) myenteric neurons and ganglionic neuropil of the mouse esophagus. We conclude that ATP might act as a neuromodulator in IGLEs via a (P2X(2))-P2X(3) receptor-mediated pathway especially in the abdominal portion of the mouse esophagus.
Kestler
Christine
C
Institut für Anatomie, Lehrstuhl I, Universität Erlangen-Nürnberg, Krankenhausstr. 9, 91054 Erlangen, Germany.
Neuhuber
Winfried L
WL
Raab
Marion
M
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D004947:Esophagus / Q000294:innervation* / Q000378:metabolism; D005724:Ganglia / Q000737:chemistry / Q000378:metabolism*; D007150:Immunohistochemistry; D051379:Mice; D008810:Mice, Inbred C57BL; D018048:Receptors, Purinergic P2 / Q000032:analysis / Q000276:immunology / Q000378:metabolism*; D058476:Receptors, Purinergic P2X2; D058477:Receptors, Purinergic P2X3; D050599:Vesicular Glutamate Transport Protein 2 / Q000032:analysis / Q000378:metabolism
C546402:P2rx2 protein, mouse; C546403:P2rx2 protein, rat; C546409:P2rx3 protein, mouse; C546410:P2rx3 protein, rat; D018048:Receptors, Purinergic P2; D058476:Receptors, Purinergic P2X2; D058477:Receptors, Purinergic P2X3; D050599:Vesicular Glutamate Transport Protein 2; D000255:Adenosine Triphosphate