[Effect of acupuncture serum on intracellular Ca2+ concentration in cultured neurons].

Objective: To study the humoral factor of acupuncture in improving functional activities of the organism.
Methods: Neurons of the cerebral cortex from the new born rats were taken to be cultured in a strictly controlled medium. Seven to ten days later, fluorescein-molecular probe Fluo-3AM was used for staining intracellular Ca(2+). Ca(2+) concentration and its changes after application of acupuncture serum were measured by using a laser confocal microscope. Normal serum and acupuncture serum were derived from the normal control rats and the rats undergoing electro-acupuncture of "Baihui (GV 20)", "Zusanli (ST 36)", "Quchi (LI 11)" and "Sanyinjiao (SP 6)" for 2 weeks.
Results: After application of normal serum, the intracellular Ca(2+) concentration increased strikingly immediately at the beginning, and gradually got stable afterwards. When acupuncture serum was added to the culture fluid, Ca(2+) concentration lowered significantly.
Conclusion: These results suggest that bioactive substances in serum collected from rats undergoing acupuncture can affect the intracellular Ca(2+) concentration of the cerebral neurons, and the humoral factor may participate in the effect of acupuncture in regulating functional activities of the organism.