H. Anisman et al., INFLUENCE OF PSYCHOGENIC AND NEUROGENIC STRESSORS ON ENDOCRINE AND IMMUNE ACTIVITY - DIFFERENTIAL-EFFECTS IN FAST AND SLOW SEIZING RAT STRAINS, Brain, behavior, and immunity, 11(1), 1997, pp. 63-74
Variations of plasma ACTH and corticosterone, as well as splenic macro
phage activity and mitogen-induced cell proliferation, were determined
in rats following 15 min of either the neurogenic stressor of restrai
nt or by a purely psychogenic stressor consisting of exposure to a fer
ret. The effects of these stressors were assessed in two strains of ra
ts that were selectively bred for either Fast or Slow kindling epilept
ogenesis triggered in response to amygdala stimulation. The stressors
differentially influenced behavioral responses, endocrine activity, an
d immune functioning, and these effects varied with the strain of rat.
In response to restraint the Fast rats exhibited protracted strugglin
g, while the Slow rats tended to be immobile. In contrast, upon ferret
exposure the Fast rats showed greater immobility than the Slow rats.
The stressors also induced marked elevations of plasma ACTH and cortic
osterone. Whereas the ACTH and corticosterone increases were more pron
ounced in response to the ferret in the Slow rats, restraint resulted
in a markedly greater rise of plasma ACTH in the Fast strain. prolifer
ation of splenic lymphocytes in response to Con A and LPS were elevate
d in Fast seizing rats, while macrophage activity, as determined by ox
ygen burst following addition of PMA and luminol to splenic mononuclea
r cells, was greater in the Slow seizing strain. While neither stresso
r influenced cell proliferation in either the Fast or Slow rats, macro
phage activity was greatly suppressed by ferret exposure only in the S
low rats. Taken together, it appears that while stressors influence be
havior and immune and endocrine functioning, these effects may vary as
a function of the interaction of the strain of rat and the specific t
ype of stressor employed. (C) 1997 Academic Press.