Influence of food intake on cold-induced vasodilatation of finger.

Abstract

When the finger is immersed in ice water, a sharp fall of the skin temperature is followed by its gradual rise due to the cold-induced vasodilatation (CIVD). The present study was attempted to examine whether the CIVD is affected by a small increase in internal heat load due to the dietary thermogenesis. A 10-min immersion of the left middle finger in ice water was performed at room temperature of 25-26 °C on 12 female subjects 60 min before, and 30 and 90 min after ingestion of a meal containing 700 kcal. Skin temperature of the finger and Oz consumption were continuously measured before, during, and after the immersion. A CIVD index was measured using the data of the rising phase of skin temperature during the immersion. The CIVD index, a newly developed parameter in the present study, could reflect both the rapidity and the magnitude of CIVD response during the immersion. Compared with pre-prandial values, the Oz consumption and the CIVD index significantly increased by 15 and 69%, respectively, at 30 min and by 15 and 50% at 90 min of the post-prandial period. Esophageal temperature was studied on another 5 subjects (1 male and 4 females) and it rose by 0.27°C during the 90-min post-prandial period. The results, in support of the involvement of the central nervous system control in CIVD, suggest that the central process is so sensitive as to operate in a 15% increase in heat load into the body.

Effect of body temperature on cold induced vasodilation

“…The present data suggest substantial loss of body heat during CIVD demonstrating its cooling capacity, which conWrms previous Wndings (Cannon and Keatinge 1960). The notion that CIVD is a heat-loss mechanism is supported in several investigations (Daanen 2003;Daanen and Ducharme 1999;Daanen et al 1997;Takano and Kotani 1989) that reported increased CIVD prevalence rates at higher levels of T b . In addition, it is generally agreed that there is a central component in CIVD given that Fig.…”

“…With the exception of CIVD 10, all CIVD events were preceded by an increase in T b . The T b threshold for the control condition was at 36.3°C (CIVD 1-3) while the equivalent was at 36.6°C when heating manipulations occurred (i.e., warming and prewarming conditions, CIVD 4-10) normothermic and/or centrally warm humans demonstrate accelerated CIVD responses (Daanen et al 1997;Takano and Kotani 1989), while those that are centrally cold reveal CIVDs of delayed onset and lesser magnitude (Daanen et al 1997;Elsner et al 1960;Keatinge 1957;Werner 1977). However, previous investigations did not arrive to the conclusions of the present study, probably because they did not assess the link between CIVD and T b in real-time but only through repeated-measures designs incorporating conditions of hyper-, hypo-, and normo-thermia.…”

“…Added to cutaneous vasoconstriction, we propose that this increased heat production may occasionally cause T b to rise (overshoot) transiently above ideal, which causes CIVD to occur in order to dissipate the excess heat. The notion that CIVD pertains paradoxically to heat dissipation is supported in several human (Daanen 2003;Daanen and Ducharme 1999;Daanen et al 1997;Takano and Kotani 1989) and animal (Grant and Bland 1931) investigations that reported higher occurrence of the phenomenon at increased T b . Yet these experiments did not assess the link between CIVD and T b in real-time, but only through repeated-measures designs incorporating conditions of hyper-, hypo-, and normo-thermia.…”

Influence of thermal balance on cold-induced vasodilation

“…Although our finding was based on finger temperature and not on actual blood flow data, it is supported by observations of a central component to CIVD (8,34,37,41,42,46). Furthermore, thermal balance has been shown to influence CIVD in a way that whole body cooling results in delayed CIVD onset (14,17,30,46), whereas increased thermogenesis (44) or body heat content (14) result in accelerated CIVD response.…”

“…Ergo, according to the deductive reasoning rule of transposition (7), since the presence of CIVD implies excess heat in a cold environment, it can be inferred that CIVD will not occur in circumstances in which excess heat is not present in a cold environment. Additional support for this notion is provided by previous investigations in different mammalian models, suggesting a correspondence between oscillations in peripheral temperature/blood flow during cold exposures and body (8,11,13,14,17,24,30,34,37,41,42,44,46) or ambient temperature (33,45). It is also generally agreed that there is a central component in CIVD, given that normothermic and/or centrally warm homoeotherms demonstrate accelerated CIVD responses (14,44), while those that are centrally cold reveal CIVDs of delayed onset and lesser magnitude (14,17,30,46).…”