FMRFamide- and neurotensin-immunoreactive elements in the intestine of some polyclad and triclad flatworms (Turbellaria).

By means of immunohistochemistry with antisera to tetrapeptide FMRFamide and regulatory peptides neurotensin and calcitonin intestines of marine turbellarians Notoplana atomata, N. humilis (Polycladida) and Procerodes littoralis (Tricladida) were investigated. In all flatworms polymorphous cells and processes reacting with antibodies to FMRFamide and neurotensin but not with calcitonin were revealed.

A revision of current data and views on membrane hydrolysis and transport in the mammalian small intestine based on a comparison of techniques of chronic and acute experiments: experimental re-investigation and critical review.

Literature data and the results of our investigations using both generally accepted and original perfusion techniques of the isolated loop of the rat small intestine in in vivo experiments are reviewed. Significant differences in the functioning of the small intestine under conditions of acute and chronic experiments are revealed. It has been established that in chronic experiments as compared to acute ones: (a) the absorption of glucose, galactose, fructose and glycine is 2-5 times higher; (b) Kt as well as Jmax values of the transport of these nutrients differ considerably; (c) Na+-independent mechanism of glucose and glycine transport predominates; (d) higher rates of membrane hydrolysis and more effective interactions between enzyme and transport systems of the enterocyte brush border membranes are observed; (e) functional characteristics of the small intestine affected by various experimental factors are more stable.