COPING WITH STRESS - PARALLELISM BETWEEN EFFECTS OF SEPTAL-LESIONS ON GROWTH-HORMONE AND CORTICOSTERONE LEVELS

  • 1 January 1976
    • journal article
    • research article
    • Vol. 11  (5) , 583-597
Abstract
To characterize the effects of a septal lesion on plasma growth hormone [GH] levels, blood samples were taken from normal and sham-operated rats and rats with a bilaterial septal lesion under conditions of rest and following stressful stimulation. Nonlesioned control rats evidenced a significant base line diurnal rhythm in plasma GH levels which was unaffected by a septal lesion. In response to stress, plasma GH levels evidenced a significant drop. Minimum levels were reached 15 min after stimulation and remained depressed during 1 h of observation after stimulation. Rats with a septal lesion evidenced the same pattern of GH response to stressful stimulation as nonlesioned rats, but the magnitude of response was potentiated in septal rats. These data were compared to the previously published corticosterone data from the same animals. A septal lesion has similar effects on both GH and corticosterone levels in that a septal lesion did not affect the resting 24 h rhythm of either of these hormones but potentiated the response of both corticosterone and GH to stress even though the direction of response is opposite. The results suggested the septum was an element in some central coping mechanism which was involved when an organism reacts to environmental demands. The same central coping mechanism was apparently involved in both the behavioral and hormonal responses to stress.