TY - JOUR
T1 - Carotid-Sinus Baroreflex Modulation of Core and Skin Temperatures in Rats
T2 - An Open-Loop Approach
AU - Zhang, Dongmei
AU - Ando, Motonori
AU - Yamasaki, Fumiyasu
AU - Sato, Takayuki
PY - 2003/12
Y1 - 2003/12
N2 - The neural mechanisms of the thermoregulatory control of core and skin temperatures in response to heat and cold stresses have been well clarified. However, it has been unclear whether baroreceptor reflexes are involved in the control of core and skin temperatures. To investigate how the arterial baroreceptor reflex modulates the body temperatures, we examined the effect of pressure changes of carotid sinus baroreceptors on core and skin temperatures in halothane-anesthetized rats. To open the baroreflex loop and control arterial baroreceptor pressure (BRP), we cut vagal and aortic depressor nerves and isolated carotid sinuses. We sequentially altered BRP in 20-mmHg increments from 60 to 180 mmHg and then in 20-mmHg decrements from 180 to 60 mmHg while measuring systemic arterial pressure (SAP), heart rate (HR), and core blood temperature (Tcore) at the aortic arch and skin temperature (T skin) at the tail. In response to the incremental change in BRP by 120 mmHg, SAP, HR, and Tcore fell by 90.3±51 mmHg, 60.3±10.5 beats min-1, and 0.18± 0.01°C, respectively. Tskin rose by 0.84±0.10°C. The maximum rate of change per unit BRP change was -2.1±0.2 for SAP, -1.5±0.4 beats min-1 mmHg-1 for HR, -0.003±0.001°C mmHg-1 for Tcore, and 0.011±0.002°C mmHg -1 for Tskin. After the administration of hexamethonium or bretylium, these baroreflexogenic responses were completely abolished. We concluded that Tcore and Tskin are modulated by the arterial baroreceptor reflex.
AB - The neural mechanisms of the thermoregulatory control of core and skin temperatures in response to heat and cold stresses have been well clarified. However, it has been unclear whether baroreceptor reflexes are involved in the control of core and skin temperatures. To investigate how the arterial baroreceptor reflex modulates the body temperatures, we examined the effect of pressure changes of carotid sinus baroreceptors on core and skin temperatures in halothane-anesthetized rats. To open the baroreflex loop and control arterial baroreceptor pressure (BRP), we cut vagal and aortic depressor nerves and isolated carotid sinuses. We sequentially altered BRP in 20-mmHg increments from 60 to 180 mmHg and then in 20-mmHg decrements from 180 to 60 mmHg while measuring systemic arterial pressure (SAP), heart rate (HR), and core blood temperature (Tcore) at the aortic arch and skin temperature (T skin) at the tail. In response to the incremental change in BRP by 120 mmHg, SAP, HR, and Tcore fell by 90.3±51 mmHg, 60.3±10.5 beats min-1, and 0.18± 0.01°C, respectively. Tskin rose by 0.84±0.10°C. The maximum rate of change per unit BRP change was -2.1±0.2 for SAP, -1.5±0.4 beats min-1 mmHg-1 for HR, -0.003±0.001°C mmHg-1 for Tcore, and 0.011±0.002°C mmHg -1 for Tskin. After the administration of hexamethonium or bretylium, these baroreflexogenic responses were completely abolished. We concluded that Tcore and Tskin are modulated by the arterial baroreceptor reflex.
KW - Baroreflex
KW - Open loop
KW - Temperature
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U2 - 10.2170/jjphysiol.53.461
DO - 10.2170/jjphysiol.53.461
M3 - Article
C2 - 15038844
AN - SCOPUS:1642503852
VL - 53
SP - 461
EP - 466
JO - Journal of Physiological Sciences
JF - Journal of Physiological Sciences
SN - 1880-6546
IS - 6
ER -