Biology Reference
In-Depth Information
3.
Physiologists and pathologists created the concept of
body integrity
, which proposed con-
tinuous interactions amongst the various tissues, organs, and systems in a coordinated and
regulated manner under both normal physiological and pathological conditions. All this
made some scientists realize that the brain must be important for the development of body
defenses; because of this recognition, relevant investigations were initiated.
2.5 Modern Immunophysiology
2.5.1 The Role of the Hypothalamus
Studies on the role of the autonomic nervous system in antibody production, which
was described as early as 1928 by Gamaleya
[17]
, led to controversial results. The
reasons for this may be at least threefold:
1.
Different authors used different, incompatible, and often inadequate methods to examine
the effects of the autonomic nervous system on immune function.
2.
The timing of antigen administration versus the influences exerted on different components
of the sympathetic nervous system was not taken into consideration.
3.
Various antigens—that is, soluble, corpuscular, toxic, nontoxic, etc.—were used, which
variously influenced the outcomes and results and thus complicated the analysis of these
experiments.
The focus of scientific investigation shifted from analysis of the effects of excision of
cervical sympathetic ganglia on immune function to studies of the effects of lesion-
ing of hypothalamic structures
[18,19]
. The experiments carried out at Speranskiy's
laboratory
[20]
provided evidence for the involvement of the hypothalamic area in
trophic processes in body tissues.
Studies of hypothalamic influences on immunological reactions using experimen-
tal lesions or excitation of the hypothalamus started with the examination of anti-
body levels and of anaphylactic shock. Fillip and Szentivanyi
[21]
were able to show
thereby that massive lesions of the hypothalamus result in inhibition of the immune
response. These findings stimulated studies of the role of hormones in the regula-
tion of immunity
[22-25]
. The earliest systematic studies along this line were done
by Fillip and co-authors
[26,27]
, who showed that massive bilateral lesioning of
the
tuber cinereum
in guinea pigs inhibited the development of anaphylactic shock.
It should be stressed that 5% of postoperative experimental animals died of severe
impairments of the vegetative and endocrine functions
[28]
. Other hypothalamic
structures have been found to be involved in regulation of NK cell activity, T-helper
and T-suppressor cell ratio
[29]
, and macrophage activity
[30]
.
The discovery of specific structures, the lesioning of which drastically reduced
immune responses
[19,31]
, initiated a new stage in study of the mechanisms of
neuroimmune interactions. The role of hormones in regulation of immunity was
examined using the model of local lesioning of the posterior hypothalamic field
[32]
. Many studies addressed the role of different structures of the brain, including
