The NPY effects on murine leukocyte adherence and chemotaxis change with age - Adherent cell implication

The two-way communication between the nervous and immune system is currentl y well-known, but the age-related changes in this communication have been s carcely studied. In the present work, we have investigated the in vitro eff ects of neuropeptide Y (NPY) at concentrations ranging from 10(-13) to 10(- 7) M on the adherence and chemotaxis capacities of spleen, axillary node, t hymus and peritoneum leukocytes from BALB/c mice. The NPY effect on these f unctions was examined on cells from animals of four different ages, i.e. yo ung (12+/-2 weeks old), adult (24+/-2 weeks old), mature (50+/-2 weeks old) and old (72+/-2 weeks old). In young animals, NPY stimulates the adherence of leukocytes from spleen, axillary nodes and thymus and inhibits it in ce lls from peritoneum. In adult animals NPY inhibits the adherence of leukocy tes from thymus. These effects disappear with ageing in all locations. Chem otaxis is stimulated by this neuropeptide at all ages in cells from axillar y nodes and peritoneum, but this effect is absent in old mice. NPY exerts a n inhibitory effect on the chemotaxis of leukocytes from thymus at all ages studied. These NPY effects on leukocytes seem to be carried out through ad herent cells. (C) 2000 Elsevier Science B.V. All rights reserved.