CALBINDIN, TYROSINE-HYDROXYLASE AND OPIOID-LIKE IMMUNOREACTIVITY IN THE INTESTINAL NERVE OF REMAK OF THE DOMESTIC-FOWL

Four classes of neurons were identified in both juxta-jejunal and juxt a-rectal ganglia of Remak's nerve of the domestic fowl using double-la beling immunohistochemistry. Neurons immunoreactive (IR) for tyrosine hydroxylase (TH) formed a mutually exclusive subpopulation from neuron s displaying calbindin (CaBP)-IR. Between 48-72% of juxta-jejunal neur ons labeled for TH whereas 36-57% of juxta-rectal neurons displayed TH -IR. CaBP-IR was present in 18-40% of juxta-jejunal neurons; this incr eased to 31-46% in juxta-rectal neurons. The majority of CaBP-IR neuro ns (78-85%) also displayed opioid (beta-EP)-IR. Within each ganglion a small percentage of neurons (4-18%) were non-IR with any of the three antibodies. This is the first report of an immunohistochemically iden tified subpopulation of non-catecholaminergic neurons within the juxta -jejunal ganglia of Remak's nerve. It is proposed that these perikarya are a major source of the CaBP-IR and opioid-IR nerve fibers found in the chicken gut.