Impaired acetylcholine-induced vascular relaxation in low birth weight infants: Implications for adult hypertension?

Low birth weight is associated with an increased risk of adult hypertension . To elucidate whether this association reflects altered vascular physiolog y already at birth, we studied acetylcholine-induced vasodilation. Forty ne wborn infants and their mothers were studied 3 d after delivery. Vasodilati on in skin was induced by local application of acetylcholine and local heat ing to 44 degrees C. Perfusion changes were measured with the laser Doppler technique. In response to acetylcholine, the mean skin perfusion increased by 240% in low birth weight infants compared with 650% in normal birth wei ght controls (p < 0.001). In contrast, mothers of low birth weight infants showed a mean increase in perfusion of 1100% after acetylcholine administra tion compared with 680% in mothers of control infants (p < 0.05). The perfu sion increase at 44 degrees C local skin temperature did not differ between the two groups of infants or between their mothers. Blood pressure was nor mal in all subjects. We conclude that low birth weight infants show signs o f endothelial dysfunction at birth. Such findings may help us understand th e link between low birth weight and adult hypertension.