| dc.description.abstract | A fever, or increased body temperature, is a symptom of inflammation, which is a complex
29 defence reaction of the organism to pathogenic infections. After pathogens enter the body,
30 immune cells secrete a number of agents, the functions of which stimulate the body to develop a
31 proper immune and fever response. In mammals is known that PGE2 is the principal mediator of
32 fever. The extent to which PGE2 and other pro-inflammatory cytokines such as TNF, IL6, or IL1-
33 could be involved in the induction of fever behaviour on fish remains to be clarified. In addition,
34 the transient receptor potential vanilloid 1 and 4 (TRPV1 and TRPV4) are believed to act as
35 monitors and regulators of thermoregulation during febrile process. As they are involved in the
36 inflammation, TRPV1 and TRPV4 would be relevant in integrating the defence response and also
37 participating in the temperature sensing. Behavioural fever testing and expression levels of both
38 TRPV1 and TRPV4 mRNA after viral challenge revealed a juxtaposed regulation of TRPV
39 channels. Notably, TRPV1 activation resulted in a significant elevation in the expression of pro40
inflammatory cytokines (IL1β, IL6, TNFα and PGE2) in the Pre Optic Area (POA) and cytokine
41 release in plasma. Together, these data indicate that the reduction of TRPV4 expression during
42 behavioural fever trigger the movement to warm places. Our data also suggest an effect of TRPV
43 channels in the regulation of behavioural fever through activation of nervous system PGTR3
44 receptors in presence of PGE2 induced by plasmatic cytokines. These results highlight for first
45 time in ectotherms the key role of pro-inflammatory cytokines and TRPV channels in the
46 behavioural fever, likely through a complex integration of prostaglandin induction, cytokine
47 recognition and temperature sensing.
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50 Keywords
51 Ectotherm, behavioural fever, cytokine, TRP channels, virus | |
