[The study of effect of pain in the change of respiration by stimulating "renzhong" acupoint].
It had been reported that the stimulation of the "Renzhong" starts respiratory activity in rabbits whose respiration has been suspended. This action was caused by stimulating Renzhong. Those signals transmit to the nucleus of trigeminal spinal, and go to influence the nucleus of respiration. Those signals include of pain and other sense. This study investigated whether this stimulation of "Renzhong" is caused by pain or another stimulus. Phrenic nerve discharges and respiratory rates of 7 anesthetized rabbits, each weighing 1.5 to 2.0 kg were recorded. Stimulation of the "Renzhong" by electrical impulses (10 ms pulse, 20 Hz, 0.4-4 mA, duration 3-5 seconds).


RESULTS
1. Stimulating the "Renzhong", resulted in an 83 +/- 16% increase in the amplitude of phrenic nerve discharges, and a 31 +/- 6% decrease in respiratory rate. 2. morphine was then injected into the rabbits (5 mg/kg). After 8 minutes, the amplitude of phrenic nerve discharges had decreased by 22 +/- 9% and the respiratory rate had decreased by 16 +/- 6%. 3. At this acupoint, stimulation of the "Renzhong" resulted in a 43 +/- 8% increase of the amplitude of phrenic nerve discharges and a 20 +/- 6% decrease in respiratory rate. These results suggest that in the effect of the stimulation of "Renzhong" on the respiration pain sensation is one factor among the rest.
Zhang
M
M
Department of physiology, Shandong Medical University, Jinan.
Zhang
H
H
Liu
L
L
D015669:Acupuncture Points; D015670:Acupuncture Therapy; D000818:Animals; D005260:Female; D008297:Male; D009020:Morphine / Q000494:pharmacology; D009619:Nociceptors / Q000502:physiology*; D010146:Pain; D010791:Phrenic Nerve / Q000502:physiology; D011817:Rabbits; D012119:Respiration; D012677:Sensation
D009020:Morphine