Differential effect of bone marrow protein on brain ATPase of immunized control and malnourished rats

After sheep erythrocyte (SRBC) immunization in balanced-diet-fed (BDF) rats, the brain microsomal ATPase activity for the first 48 h was suppressed compared with preimmunization level, then stimulated at the peak of the immune response. In contrast, rats malnourished by deprivation of vitamin B complex and ascorbic acid and with significantly lower pre- and postimmunization enzyme activity than the BDF rats, had stimulated enzyme activity only on immunization, and their immune response was found to be suppressed. A bone marrow-derived bioimmunomodulator (BIM) revived the immunocompetence of the malnourished immunized animals, and brain ATPase activity in these animals after BIM injection followed a pattern similar to that of the immunized BDF rats. We suggest that, after SRBC immunization under the influence of BIM, suppression followed by stimulation of the brain microsomal ATPase might be related to immune response.