Activity-wheel running blunts suppression of splenic natural killer cell cytotoxicity after sympathectomy and footshock

• Published in: Physiology & behavior Vol. 71; no. 3-4; pp. 297 - 304
• Main Authors: Dishman, R.K, Hong, S, Soares, J, Edwards, G.L, Bunnell, B.N, Jaso-Friedmann, L, Evans, D.L
• Format: Journal Article
• Language: English
• Published: Cambridge Elsevier Inc 01.11.2000; New York, NY Elsevier
• Subjects: 6-Hydroxydopamine; Animals; autonomic; Biological and medical sciences; Body Weight; Cytotoxicity, Immunologic - physiology; Electroshock; Exercise; Foot; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Immune system; Immunobiology; Killer Cells, Natural - physiology; Modulation of the immune response (stimulation, suppression); Motor Activity - physiology; Nervous system; Norepinephrine; Norepinephrine - metabolism; Rats; Rats, Inbred F344; Spleen - physiology; Sympathectomy; Nervous system; Norepinephrine; Exercise; 6-Hydroxydopamine; Immune system; Electrical stimulus; Rodentia; Rattus norvegicus; Cytotoxicity; Immune sympathectomy; Sympathetic nervous system; Vertebrata; Animal activity; Mammalia; Spontaneous physical activity; Investigation method; Autonomic nervous system
• ISSN: 0031-9384; 1873-507X
• DOI: 10.1016/S0031-9384(00)00329-2

We used chemical sympathectomy by 6-hydroxydopamine (6-OHDA) to examine whether adaptation by the sympathetic nervous system (SNS) is a plausible explanation for our prior finding that activity-wheel running blunts the suppression of splenic natural killer cell cytotoxicity after footshock. Male Fischer rats were assigned to treatments using a group (activity wheel vs. sedentary)×treatment (6-OHDA vs. saline)×condition (footshock vs. no shock) design. After 5–6 weeks, rats were injected i.p. with saline or with 40, 80, and 80 mg/kg 6-OHDA on pre experimental days −5, −3, and −1. Half the rats received 6 min of random footshock during a 40-min period. Cytotoxicity was determined by standard 4-h 51Cr release assay. Sympathectomy reduced splenic [NE] by 72%. After 6-OHDA injection and footshock, percent lysis was 33% lower in sedentary rats compared with activity-wheel runners and home-cage controls, p=0.048. The results suggest that activity-wheel running leads to adaptations that offset an altered SNS modulation of splenic NK cell cytotoxicity in response to footshock.