Hypothalamic Corticotropin-releasing factor (CRF) directly activates the hypothalamic pituitary adrenal axis (HPA axis) during the surgical trauma induced stress response. Electroacupuncture (EA) has been demonstrated...Hypothalamic Corticotropin-releasing factor (CRF) directly activates the hypothalamic pituitary adrenal axis (HPA axis) during the surgical trauma induced stress response. Electroacupuncture (EA) has been demonstrated to have stress relieving effects in breast surgery, colorectal surgery, prostatectomy and craniotomy. This study was aimed to investigate the hypothesis that EA could regulate hypothalamic CRF in surgical trauma rats. In experiment one, Sprague-Dawley (SD) male rats were divided into intact, model (10% partial hepatectomy), sham EA and EA group. Rats from the Sham EA and EA group were stimulated at ST36-Zusanli and SP6-Sanyiniiao acupoints twice, 24 hours before the surgery and immediately after the surgery. Expressions of hypothalamic CRF and CRFR, GABA receptors, glutamate decarboxylase (GAD), serum adrenocorticotropic hormone (ACTH) and Corticosterone (CORT) were observed at 2, 4, 8 and 24 h after the surgery by radioimmunoassay (RIA), western blot, real-time PCR and immunohistochemistry. In the experiment two, SD male rats were divided into the intact, model, model + vehicle, model + L-838,417 EA and EA + L838,417 group. It was found that hypothalamus CRF, serum ACTH and CORT levels were increased in model group compared with the intact group, and those in the EA group decreased in comparison with the model group. Compared with the model group, hypothalamus-aminobutyric acid (GABA) receptor Aα3 mRNA and protein expressions of the EA group raised strikingly. In conclusion, EA alleviated surgical stress response by improving the GABA synthesis in hypothalamus, thus enhancing GABA receptors’ inhibitory regulation of the HPA axis dysfunction in rats with acute surgical trauma.展开更多
The effects of γ-aminobutyric acid (GABA) and its antagonists bicuculline and 2-hydroxysaclofen on neuronal firings in the nucleus of basal optic root (nBOR) in pigeons were studied by using extracellular recording a...The effects of γ-aminobutyric acid (GABA) and its antagonists bicuculline and 2-hydroxysaclofen on neuronal firings in the nucleus of basal optic root (nBOR) in pigeons were studied by using extracellular recording and microiontophoretic techniques. The results suggest that GABA may be an inhibitory neurotransmitter or modulator within nBOR, functioning by means of main mediation of GABAA receptors and of minor mediation of GABAB receptors. Furthermore, GABA and its GABAA receptors are involved in the modulation of directional selectivity in part of nBOR neurons.展开更多
Intracellular recordings were made from amacrine cells in the isolated, superfused carp retina, and the effects of γ-aminobutyric acid (GABA) on sustained and transient ON signals of these cells were studied. Exogeno...Intracellular recordings were made from amacrine cells in the isolated, superfused carp retina, and the effects of γ-aminobutyric acid (GABA) on sustained and transient ON signals of these cells were studied. Exogenous GABA application partially suppressed the sustained response of ON amacrine cells, which could be completely reversed by picrotoxin (PTX), a chloride channel blocker, and by bicuculline (BCC), a specific GABA_A receptor antagonist. On the other hand, suppression by GABA of the ON response which was predominantly driven by rod signals in a certain portion of transient ON-OFF amacrine cells was completely blocked by PTX, but not by BCC, indicating that GABA_C receptors may be involved in the effect. These results suggest that GABA_A and GABA_C receptors may be respectively involved in mediating the transmission of sustained and transient signals in the carp inner retina.展开更多
文摘Hypothalamic Corticotropin-releasing factor (CRF) directly activates the hypothalamic pituitary adrenal axis (HPA axis) during the surgical trauma induced stress response. Electroacupuncture (EA) has been demonstrated to have stress relieving effects in breast surgery, colorectal surgery, prostatectomy and craniotomy. This study was aimed to investigate the hypothesis that EA could regulate hypothalamic CRF in surgical trauma rats. In experiment one, Sprague-Dawley (SD) male rats were divided into intact, model (10% partial hepatectomy), sham EA and EA group. Rats from the Sham EA and EA group were stimulated at ST36-Zusanli and SP6-Sanyiniiao acupoints twice, 24 hours before the surgery and immediately after the surgery. Expressions of hypothalamic CRF and CRFR, GABA receptors, glutamate decarboxylase (GAD), serum adrenocorticotropic hormone (ACTH) and Corticosterone (CORT) were observed at 2, 4, 8 and 24 h after the surgery by radioimmunoassay (RIA), western blot, real-time PCR and immunohistochemistry. In the experiment two, SD male rats were divided into the intact, model, model + vehicle, model + L-838,417 EA and EA + L838,417 group. It was found that hypothalamus CRF, serum ACTH and CORT levels were increased in model group compared with the intact group, and those in the EA group decreased in comparison with the model group. Compared with the model group, hypothalamus-aminobutyric acid (GABA) receptor Aα3 mRNA and protein expressions of the EA group raised strikingly. In conclusion, EA alleviated surgical stress response by improving the GABA synthesis in hypothalamus, thus enhancing GABA receptors’ inhibitory regulation of the HPA axis dysfunction in rats with acute surgical trauma.
基金Project supported by the National Natural Science Foundation of China and Amherst College.
文摘The effects of γ-aminobutyric acid (GABA) and its antagonists bicuculline and 2-hydroxysaclofen on neuronal firings in the nucleus of basal optic root (nBOR) in pigeons were studied by using extracellular recording and microiontophoretic techniques. The results suggest that GABA may be an inhibitory neurotransmitter or modulator within nBOR, functioning by means of main mediation of GABAA receptors and of minor mediation of GABAB receptors. Furthermore, GABA and its GABAA receptors are involved in the modulation of directional selectivity in part of nBOR neurons.
基金Project supported by the State Commission of Science and Technology of China (Climbing Project)the National Natural Science Foundation of China (Grant Nos. 39670253 and 39770256)the National Research Center of Life Science of China (Shanghai)
文摘Intracellular recordings were made from amacrine cells in the isolated, superfused carp retina, and the effects of γ-aminobutyric acid (GABA) on sustained and transient ON signals of these cells were studied. Exogenous GABA application partially suppressed the sustained response of ON amacrine cells, which could be completely reversed by picrotoxin (PTX), a chloride channel blocker, and by bicuculline (BCC), a specific GABA_A receptor antagonist. On the other hand, suppression by GABA of the ON response which was predominantly driven by rod signals in a certain portion of transient ON-OFF amacrine cells was completely blocked by PTX, but not by BCC, indicating that GABA_C receptors may be involved in the effect. These results suggest that GABA_A and GABA_C receptors may be respectively involved in mediating the transmission of sustained and transient signals in the carp inner retina.
