title: Effects of timing acupuncture on nuclear volume of neurosecretory cells in rat supraoptic nucleus.
abstract: To see whether the effects of acupuncture on the nuclear volume of neurosecretory cells in the rat supraoptic nucleus (SON) are circadian stage-dependent, 48 male Wistar rats were divided into eight equal groups and standardized in LD12:12 at 21.5 degrees C with food and water ad libitum. At each of four time points [0, 6, 12, and 18 hours after lights on (HALO)], one group (A) was treated by electric acupuncture at a place equivalent to the human "Yongquan" point; another group (C) was left untreated as a control without acupuncture. The nuclear volumes of neurosecretory cells were calculated after the nuclei were measured with a micrometer under a microscope. Circadian variation in nuclear volume was observed for both A and C groups and showed macroscopically two peaks, one at 18 HALO and another at 6 HALO, and a nadir at the time of lights on (0 HALO). The effects of acupuncture appear to differ at various time points. A circadian change in the ratio of the data from the A and C groups at each time point was observed only in the left SON and peaked at 0 HALO. An asymmetry between the left and right SONs characterized their changes and responses to acupuncture. An analysis of variance established a time effect (P less than 0.001) and an interaction between laterality and treatment (P less than 0.037). The results documenting a circadian change of nuclear volume of the SON neurosecretory cells and a laterality-dependent response to acupuncture point to cephalic mechanisms of "Ziwu Liuzhu" chronotherapy by acupuncture and moxibustion.
mesh_terms: D015670:Acupuncture Therapy; D000818:Animals; D002467:Cell Nucleus / Q000648:ultrastructure; D002940:Circadian Rhythm; D008297:Male; D009490:Neurosecretory Systems / Q000648:ultrastructure*; D051381:Rats; D011919:Rats, Inbred Strains; D013495:Supraoptic Nucleus / Q000648:ultrastructure*