ABSTRACT
Objective:To investigate the effects of the β-casomorphin-7 on in vitro and in vivo mice splenic lymphocyte and macrophage nitric oxide production.Methods:Splenocytes proliferation assay and nitrite determination were employed for the studies of effects of β-casomorphin-7 on mice splenic lymphocyte and macrophage following in vitro stimulation of β-casomorphin-7 and in vivo intrapetitoneal administration and drinking β-casomorphin-7 solution administration.Results:In vitro study, β-casomorphin-7 showed a stimulation as well as a suppression of lymphocyte proliferation and significantly(P＜0.01) suppressed the production of nitric oxide. In vivo study, β-casomorphin-7 actions on lymphocytes and macrophages were accordant in intraperitoneal administration and drinking β-casomorphin-7 solution administration. β-casomorphin-7 significantly(P＜0.01) increased in splenic lymphocyte proliferative response and suppressed nitric oxide production in peritoneal macrophages.Conclusion:The present study indicates that the β-casomorphin-7 has the immunomodulatory effects and β-casomorphin-7 may be permeable into peripheral blood intact in mice of 2-3 weeks of age.
ABSTRACT
Objective: The aim of the present study was to evaluate the stability of native bovine ? casomorphin 7 in duodenum of adult rats, and the local effect on expression of cholecystokinin in intestinal mucosa. Method: (1) According to the variety of infused ? casomorphin 7 concentrations between absorptive and un-absorptive groups in vivo, its characteristic absorption in duodenum was observed. (2) To characterize the stability of the ? casomorphin 7, rat intestinal mucosa homogenate was digested and the enzyme activities were determined in vitro. (3) The effect on cholecystokinin mRNA expression of ? casomorphin 7 after luminal administration was analyzed by RT-PCR. Results:? casomorphin 7 was unable to be absorbed by intestinal epithelia and quickly degraded in the intestinal tract. It contributed to elevate cholecystokinin mRNA expression in intestinal mucosa and this effect was partly blocked by naloxone. This peptide also significantly inhibited the somatostatin mRNA expression. Conclusion: The present data demonstrated that the local effect on expression of cholecystokinin of ? casomorphin 7 might be related to opioid system and directly or indirectly affected by somatostatin.