[The effects of nucleus central lateralis on the unit discharges in posterior group of thalamic nuclei evoked by splanchnic afferents in cats].
The effects of the nucleus central lateralis (CL) on the unit discharges evoked by the splanchnic afferents in the posterior group of thalamic nuclei (PO) were studied with extracellular microelectrode techniques. In 35 cate, 96 units (98%) producing evoked discharges in PO with the latency range of 30-150ms were observed. The evoked discharges of 69 units in PO were depressed by stimulating CL with a short train of electric pulse through a bipolar electrode, but the other 27 units were uninfluenced. The inhibition of CL can be classified into 3 forms: the instant inhibition, the delayed inhibition and the continued inhibition. The injection of picrotoxin (1%, 40 microliters) into lateral ventricles of the brain could invert the inhibitory effects of PO cells caused by stimulating CL. The results suggest that there may be direct nervous pathway from CL to PO and some of these neurons may function with GABA as neurotransmitter. The CL may execute the instant inhibition through the nervous pathway. It is concluded that CL has inhibitory effect on visceral pain and GABA is involved in the inhibitory process.
Zhu
Q
Q
Department of physiology, Shenyang medical College, Liaoning.
Teng
G
G
D000818:Animals; D004558:Electric Stimulation; D005071:Evoked Potentials; D005260:Female; D008297:Male; D009475:Neurons, Afferent / Q000502:physiology; D013153:Splanchnic Nerves / Q000502:physiology*; D013787:Thalamic Nuclei / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000502:physiology
D005680:gamma-Aminobutyric Acid