Central administration of immunomodulatory factors alters neural activity and adrenocortical secretion.
This study was designed to examine the effects of intracerebroventricular administration of a variety of immunomodulatory factors upon cortical EEG, preoptic area/anterior hypothalamic (POA/AH) multiunit activity (MUA), and corticosterone secretion in conscious, freely moving rats. The substances tested were alpha-interferon (alpha-INF), thymic humoral factor (THF), histamine, and interleukin-1 (IL-1). Saline administration did not alter POA/AH MUA up to 45 min after injection but increased the total time and duration of synchronized EEG periods. alpha-INF and THF were found to significantly reduce POA/AH MUA and increased the amount and duration of synchronized EEG while decreasing basal plasma corticosterone levels. Histamine and IL-1 did not alter POA/AH MUA discharge but decreased EEG synchronization and evoked an increase in plasma corticosterone levels. These results demonstrate that some secretions of the immune system are able to alter EEG discharge and neural activity in an area of the brain known to modulate both immune and neuroendocrine secretory activity. The results also appear to be related to adrenocortical secretory activity, which was altered by the substances tested.
Kidron
D
D
Department of Neurology, Hadassah University Hospital, Jerusalem, Israel.
Saphier
D
D
Ovadia
H
H
Weidenfeld
J
J
Abramsky
O
O
D000302:Adrenal Cortex / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000276:immunology* / Q000502:physiology; D003345:Corticosterone / Q000097:blood; D004569:Electroencephalography; D006632:Histamine / Q000494:pharmacology*; D007372:Interferons / Q000494:pharmacology*; D007375:Interleukin-1 / Q000494:pharmacology*; D008297:Male; D009490:Neurosecretory Systems / Q000187:drug effects*; D051381:Rats; D013935:Thymic Factor, Circulating / Q000494:pharmacology*; D013951:Thymus Hormones / Q000494:pharmacology*
D007375:Interleukin-1; D013951:Thymus Hormones; D006632:Histamine; D007372:Interferons; D013935:Thymic Factor, Circulating; D003345:Corticosterone