Sex difference in peripheral arterial response to cold exposure.
ABSTRACT In Japan, there is a symptom commonly referred to as "Hie-sho", which is a feeling of coldness or chill in a particular part of the body, and it can sometimes be unendurable. This phenomenon is known to occur more frequently in women. The present study used synchrotron radiation micro-angiography (SRMA) to examine the hypothesis that this feeling is derived from a sex difference in the vascular response to coldness.
The hind limb of male (Group M) and female (Group F) Wistar rats was exposed to cold and the tissue temperature was recorded. SRMA with a spatial resolution of 26 microm was used to measure arterial diameter. The reduction in temperature brought on by cold exposure was significantly larger in Group F than in Group M (p<0.05). SRMA showed that the arteries were dilated by cold exposure in both groups; however, the percentage dilatation in response was statistically small in Group F (69+/-40%) compared with Group M (118+/-73%) (p<0.05).
Arteries in the limbs of female rats did not expand as much as those of the males in response to cold exposure, which may explain why women feel the cold more than men.
- SourceAvailable from: circres.ahajournals.orgCirculation Research 06/2004; 94(10):1273-5. · 11.86 Impact Factor
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ABSTRACT: Women are far more likely than men to suffer from Raynaud's disease. The purpose of this study was to determine whether there are gender differences in local or central control of cutaneous blood flow that could account for the increased incidence of Raynaud's disease in women. To assess cutaneous blood flow, hand blood flow (HBF), finger blood flow (FBF), or skin perfusion (SP) was measured by fluid plethysmography, mercury strain-gauge plethysmography, or laser Doppler spectroscopy, respectively, in 47 volunteers. Basal HBF in men exceeded that of women (12.1 +/- 2.0 versus 6.2 +/- 1.5 ml/100 ml/min). Likewise, FBF in men surpassed that of women (19.5 +/- 4.1 versus 7.7 +/- 1.8 ml/100 ml/min). Similarly, SP in men was greater than that of women (270 +/- 42 versus 81 +/- 16 perfusion units). However, after total body warming (to induce a thermal sympatholysis), HBF in women exceeded that of men, suggesting that the lower basal HBF in women was due to increased sympathetic outflow to the extremities. Mental stress and deep inspiration reduced HBF and SP in men. Paradoxically, both of these maneuvers increased HBF and SP in women. To determine whether these paradoxical responses in women were due to the women's elevated basal sympathetic tone, these experiments were repeated after total body cooling in men to increase sympathetic tone and after total body warming in women to reduce sympathetic tone. Total body cooling reduced HBF and SP in men. Under these conditions, mental stress and deep inspiration induced vasodilation. In women, total body warming for 10 minutes increased HBF.(ABSTRACT TRUNCATED AT 250 WORDS)Circulation 12/1990; 82(5):1607-15. · 15.20 Impact Factor
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ABSTRACT: The use of a laser Doppler flowmeter to detect microcirculatory impairment and abnormalities in sympathetic neural control of blood flow in the hands and feet was evaluated. Measurements were carried out in 15 insulin dependent diabetic patients with retinopathy, 14 uncomplicated diabetics and 15 normal subjects. Three tests were assessed (1) the hyperaemic response of the skin microcirculation to local heating at 44 degrees C; (2) the reactive hyperaemic response of the skin microcirculation to 2 min arterial occlusion; and (3) the peripheral vasoconstrictor reflexes to cold challenge and inspiratory gasp. Tests (1) and (2) were applied to the dorsum of the hand and foot and test (3) to the pulp of the fingertip and toe. All tests were carried out with the subjects peripherally vasodilated by indirect heating. At the hand no differences were found between the groups for any of the measures. The hyperaemic response to local heating at the dorsum of the foot showed that the maximum flow in complicated diabetics was significantly lower than that in uncomplicated patients (P less than 0.01) and in normal subjects (P less than 0.002). A new measure, the time for flow to increase to 3 times basal flow, was longer in the complicated group compared with the uncomplicated (P less than 0.02) and the normal groups (P less than 0.001). This test also showed that the response in the uncomplicated group was slower than in the normal group (P less than 0.01). The post-occlusive hyperaemic response did not differ between groups. Measurement of vasoconstrictor reflexes showed that the complicated group had a poorer response to cold challenge at the big toe than the uncomplicated group (P less than 0.02) and the complicated group generally tended to have poorer responses than the other two groups. In conclusion, we have found that the hyperaemic response to local heating can detect microvascular impairment in diabetes before other complications become apparent and that the vasoconstriction test may be able to identify individuals with peripheral sympathetic neuropathy.Clinical Physiology 04/1992; 12(2):195-208.