5-Hydroxytryptamine 1A receptor activation reduces cutaneous vasoconstriction and fever associated with the acute inflammatory response in rabbits

Department of Physiology, Centre for Neuroscience, Flinders Medical Centre, Flinders University, 5042 SA, Bedford Park, Australia.
Neuroscience (Impact Factor: 3.36). 02/2004; 123(1):1-4. DOI: 10.1016/j.neuroscience.2003.09.021
Source: PubMed


5-Hydroxytryptamine1A (5-HT1A) receptor activation reduces body temperature partially by dilating the thermoregulatory cutaneous vascular bed, thereby increasing heat transfer to the environment. Constriction of this vascular bed, with consequent reduction of heat transfer to the environment, contributes to fever associated with the acute inflammatory response. Thus activation of 5-HT1A receptors might inhibit thermoregulatory cutaneous vasoconstriction and reduce the fever associated with the acute inflammatory response. The present study tested this hypothesis in conscious unrestrained rabbits. The acute inflammatory reaction was induced with i.v. lipopolysaccharide (LPS, 0.5 μg/kg). Body temperature was measured with an i.p. telemetric probe, and ear pinna blood flow was measured with a chronically implanted Doppler ultrasonic probe. 5-HT1A receptors were activated with i.v. 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT).

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