Abstract
Present study was undertaken to investigate responses of ovarian blood flow (OBF) to electro-acupuncture (EA) stimulation at different frequencies (2 and 80 Hz) and intensities (1.5, 3 and 6 mA) in anaesthetised rats. OBF was measured on the surface of the left ovary using laser Doppler flowmetry. Acupuncture needles with a diameter of 0.3 mm were inserted bilaterally into the abdominal and the hindlimb muscles and connected to an electrical stimulator. Both low (2 Hz)- and high (80 Hz) -frequency EA at 1.5 mA and high-frequency EA at 3 mA had no effect on OBF. Low-frequency EA at 3 and 6 mA elicited significant increases in OBF. In contrast, high-frequency EA with an intensity of 6 mA evoked significant decreases in OBF, followed by decreases in MAP. After severance of the ovarian sympathetic nerves, the increases in the OBF responses to low-frequency EA at 3 and 6 mA were totally abolished, and the responses at 6 mA showed a tendency to decrease, probably because of concomitant decreases in MAP. The decreased OBF and MAP responses to high-frequency EA at 6 mA remained after the ovarian sympathectomy, and the difference in the responses before and after ovarian sympathectomy was not significant. The present study showed that low-frequency EA stimulation increases OBF as a reflex response via the ovarian sympathetic nerves, whereas high-frequency EA stimulation decreases OBF as a passive response following systemic circulatory changes. [Jpn J Physiol 54 Suppl:S200 (2004)]
