Effects Of β-endorphin On The Immunoregulation Of Neverita Reiniana

β-endorphin is a important neuropeptide, and has lately been found play an key role in the modulation of immunity.Using the immunohistochemical technique, nerve cell bodies and fibres immunoreactive to the anti-β-endorphin sera were observed in the cerebral ganglia, pedal ganglia, visceral and ganglia of Neverita reiniana.β-endorphin (β-EP) immunoreactivity was also localized in the epithelium of the buccal bulb,stomach, rectum, liver, esophageal gland, gill, mantal, pedal, kidneys and immunocytes of Neverita reiniana. By the same method, delta-, mu-, and kappa receptors were detected on cerebral ganglia, pedal ganglia and visceral ganglia of Neverita reiniana. These receptors were also localized in the epithelium of the buccal bulb,stomach, rectum, liver, esophageal gland, gill, mantal, pedal, kidneys and immunocytes of Neverita reiniana. Sinceβ-EP and opioid receptors are very abundant in many tissues of Neverita reiniana.,β-EP may engage in receptor-mediated immunity, digestion, breath and excretion activities.To study the effects ofβ-EP on immunoregulation of Neverita reiniana, the content of nitric oxide ( NO) , hydrogen peroxide(H2O2) and four kinds of enzymes participating in the immune defence in the haemolymph of Neverita reiniana were assayed after 1, 5, 10μg/mlβ-EP were added into the haemolymph. The results are as follows. (1) The catalase (CAT) activities in the serum were enhanced with increasing concentration of theβ-EP and the levels of H2O2 in the serum was enhanced at the low concentration of theβ-EP and decreased at the high concentration of theβ-EP. (2)β-EP decreased plasma levels of NO significantly as its concentration rise. (3) The myeloperoxidase (MPO) activities in serum of Neverita reiniana were enhanced at the low concentration of theβ-EP and decreased at the high concentration of theβ-EP. (4)β-EP has no effect onα-Naphthy Acetate Esterase activities ,but restrain the ANAE activities at higher concentration. (5)β-EP restrict the ACP activation in serum of Neverita reiniana but the restriction reduct as the concentration ofβ-EP rise. Overall, the data strongly suggests an involvement ofβ-EP in the regulation and improvement of the immune processes of Neverita reiniana.