{'fraction_non_alphanumeric': 0.03247631935047361, 'fraction_numerical': 0.006765899864682003, 'mean_word_length': 4.987854251012146, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
[Effect of intracerebral injection of substance P on serotonin contents of several brain regions and its relation with pain threshold, electroacupuncture analgesia in rats].

The purpose of this study is to observe the effect of intracerebroventricular (icv) and intra-PAG injection of substance P (SP) on serotonin (5-HT) contents of hypothalamus, hippocampus, striatum and its relation with the change of pain threshold, electroacupuncture (EA) analgesia. The results were as follows: (1) After icv injection of SP, the pain threshold and the 5-HT contents of hypothalamus, hippocampus were significantly increased. After depletion of the 5-HT contents in brain by pCPA, the inhibitor of 5-HT synthesis, the effect of SP on elevating pain threshold and the 5-HT contents of hypothalamus, hippocampus were markedly attenuated, bud did not prevent the analgesic effect of SP (2) The pain threshold and the 5-HT contents of hypothalamus, hippocampus were dose-dependently increased by intra-PAG injection of SP. (3) The intra-PAG injection of SP introduced simultaneously with high or low frequency EA did not affect the change of 5-HT contents of three brain regions, but caused a more marked elevation of pain threshold. These results suggest that the serotoninergic system may be activated by PAG for the mediation of SP induced analgesia. There is a synergic action of analgesia between the effects produced by intra-PAG injection of SP and those by high or low frequency EA.