Electrophysiology and morphology of vasoactive-intestinal-peptide-immunoreactive neurones of the XXXX ileum.

@entity840 @entity6891 @entity121
Simultaneous intracellular staining and electrophysiological recording techniques have been applied to neurones of @entity840 myenteric @entity121 . With micro-electrodes filled with a solution of the fluorescent dye Lucifer Yellow, neurones were first characterized morphologically and electrophysiologically, and subsequently subjected to an indirect immunohistochemical method for the detection of vasoactive intestinal peptide ( @entity6891 )-like immunoreactivity. Cross-correlations of morphology, electrophysiology and @entity6891 immunoreactivity were successfully achieved in a total of 164 neurones. Sixty-three had the slow after-hyperpolarization characteristic of AH neurones; 101 cells displayed fast excitatory post-synaptic potentials (e.p.s.p.s) in response to transmural or focal stimulation and were therefore, by definition, S neurones. Unequivocal @entity6891 immunoreactivity was observed in 25 (25%) S neurones, which, with only one exception, had Dogiel Type I morphology (i.e. many short soma processes and a single long process). In contrast, AH neurones had Dogiel Type II morphology (i.e. smooth soma with several long processes) and none showed @entity6891 immunoreactivity. In addition to cholinergic fast e.p.s.p.s., non-cholinergic slow synaptic inputs were evoked in seventeen of the twenty-two @entity6891 -immunoreactive S neurones tested. Both the fast and slow e.p.s.p.s could be elicited by stimulation of the preparation, oral or aboral to the site of recording. These observations demonstrate that, in the @entity840 ileum, myenteric plexus neurones showing @entity6891 immunoreactivity are of a single electrophysiological type (S neurones) and belong to essentially one morphological class (Dogiel Type I).
