Strain-specific enhancement of splenic T cell mitogenesis and macrophage phagocytosis following peripheral axotomy.
The inbred mouse strains C57BL/6 and DBA/2 were subjected to the selective depletion of peripheral nervous system norepinephrine (NE) by the administration of the neurotoxin 6-hydroxydopamine (6-OH-DA). Measurement of mitogen-induced lymphocyte proliferation following peripheral axotomy with 6-OH-DA revealed that significant enhancement (up to 200% of control values) of T, but not B, cell proliferative responses occurred in DBA/2, while no effect was observed in C57BL/6. Enhancement (up to 196% of control values) of luminol-enhanced chemiluminescence resulting from the phagocytosis of opsonized zymosan was also observed following 6-OH-DA treatment in DBA/2, but not C57BL/6. This strain-specific enhancement of immune responses occurred even though the administration of 6-OH-DA resulted in a similar depletion of splenic NE content (greater than 97% reduction of control values) in both strains as determined by high-pressure liquid chromatography-electrochemical detection. Blockage of the neurotoxic effects of 6-OH-DA was achieved by the use of the catecholamine uptake blocker desipramine-HCl. Administration of desipramine prior to 6-OH-DA blocked the reduction of splenic NE content and abrogated the enhancement of mitogen-induced T cell proliferation. The enhancement of phagocytosis by 6-OH-DA was not, however, altered by the prior administration of desipramine.
Lyte
M
M
Department of Biological Sciences, Mankato State University, MN 56002.
Ernst
S
S
Driemeyer
J
J
Baissa
B
B
D000818:Animals; D006892:Hydroxydopamines / Q000494:pharmacology; D008213:Lymphocyte Activation; D008264:Macrophages / Q000276:immunology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009638:Norepinephrine / Q000502:physiology; D016627:Oxidopamine; D010587:Phagocytosis; D013045:Species Specificity; D013564:Sympathetic Nervous System / Q000502:physiology*; D013601:T-Lymphocytes / Q000276:immunology*
D006892:Hydroxydopamines; D016627:Oxidopamine; D009638:Norepinephrine