Pia arachnoid contains substance P originating from trigeminal neurons.
Immunoreactive substance P is present in measurable amounts in pia arachnoid from rat, cat, dog and calf. Levels of substance P in this tissue are comparable to those found in peripheral structures receiving innervation from dorsal root or trigeminal ganglia. Separation and measurement of bovine pia-arachnoid extract by reverse phase high performance liquid chromatography and radioimmunoassay reveals a single peak of activity with a retention time identical to that of substance P. Unilateral lesions of the trigeminal ganglia decrease substance P levels within cat pia arachnoid and accompanying blood vessels ipsilaterally by greater than 50%. These data indicate that most of the substance P surrounding pial blood vessels resides within afferent nerve fibres from trigeminal ganglion cells.
D000818:Animals; D001099:Arachnoid / Q000032:analysis / Q000033:anatomy & histology*; D002415:Cats; D002417:Cattle; D002536:Cerebral Arteries / Q000294:innervation; D004285:Dogs; D009475:Neurons, Afferent / Q000032:analysis; D010841:Pia Mater / Q000032:analysis / Q000033:anatomy & histology*; D051381:Rats; D013373:Substance P / Q000032:analysis*; D012668:Trigeminal Ganglion / Q000601:surgery; D014276:Trigeminal Nerve / Q000032:analysis / Q000033:anatomy & histology*
D013373:Substance P