Record Details

Neural regulation of immunity in teleosts

ScholarsArchive at Oregon State University

Field Value
Title Neural regulation of immunity in teleosts
Names Flory, Craig M. (creator)
Bayne, Christopher J. (advisor)
Date Issued 1988-06-03 (iso8601)
Note Graduation date: 1989
Abstract It has long been observed that stress can increase our
susceptibility to infectious diseases and cancers. Recent
experimental evidence suggests that this increased susceptibility is
due to suppression of immunity. A variety of neuroendocrine products
are released during periods of stress, and a large number of these
are now known to influence leukocyte function via a receptor
mediated process. Indeed, the capacity for neural and hormonal
regulation of immunity in mammals is now well established. Direct
neural control of immune reactivity is evidenced by the extensive
autonomic innervation of lymphoid tissues, the effects of
denervation on immunity, the presence of high affinity receptors for
autonomic neurotransmitters on leukocyte membranes, and the
multitude of leukocyte functions which can be altered by adrenergic
and cholinergic agents in vitro.
This thesis demonstrates that the immune systems of certain
teleosts are also susceptible to some degree of neural control. The
spleen of the coho salmon, Oncorhynchus kisutch, contains a rich
adrenergic innervation. Depletion of peripheral catecholamine stores
with 6-hydroxydopamine (6 -OHDA) resulted in an increased number of
antibody-secreting cells in the spleens of subsequently immunized
fish. 6 -OHDA treatment did not influence plasma cortisol levels, and
did not affect the antibody response if administered one week after,
rather than two days prior to, immunization.
Agonists of adrenergic and cholinergic receptors significantly
influenced the in vitro activity of leukocytes from the rainbow
trout, Salmo gairdneri. Agonists of beta-adrenergic receptors
suppressed the in vitro antibody-secreting cell response and
mitogen induced proliferation of leukocytes from the spleen, and the
chemiluminescent response of pronephric leukocytes. The suppression
induced by beta-receptor agonists could be blocked by beta-receptor
antagonists. Agonists of alpha-adrenergic and cholinergic receptors
enhanced both the in vitro antibody response and the
chemiluminescent response. These effects were also blocked by the
appropriate receptor antagonists. Alpha and cholinergic agonists had
no effect on the mitogenic response. The alpha agonist-induced
enhancement of the antibody response was found to be mediated by
alpha-2 adrenergic receptors on rainbow trout splenic leukocytes.
Genre Thesis/Dissertation
Topic Osteichthyes -- Immunology
Identifier http://hdl.handle.net/1957/41087

© Western Waters Digital Library - GWLA member projects - Designed by the J. Willard Marriott Library - Hosted by Oregon State University Libraries and Press