{"doi":"10.17615/1fec-yr59","title":"The relationship of allopregnanolone immunoreactivity and HPA-axis measures to experimental pain sensitivity: Evidence for ethnic differences☆","abstract":"In animal models, allopregnanolone (ALLO) negatively modulates the hypothalamic-pituitary-adrenal (HPA) axis and has been shown to exert analgesic effects. The purpose of this study was to assess the relationship between plasma ALLO immunoreactivity (ALLO-ir), HPA-axis measures, and pain sensitivity in humans. Forty-five African Americans (21 men, 24 women) and 39 non-Hispanic Whites (20 men, 19 women) were tested for pain sensitivity to tourniquet ischemia, thermal heat, and cold pressor tests. Plasma ALLO-ir, cortisol, and β-endorphin concentrations were taken following an extended rest period. Lower concentrations of ALLO-ir were associated with increased pain tolerance to all three pain tests and increased pain threshold to the thermal heat pain task in the non-Hispanic Whites only (rs = -.35 to -.49, ps < .05). Also, only in the non-Hispanic Whites was cortisol associated with thermal heat tolerance (r = +.39, p<.05) and threshold (r = +.50, p < .01) and cold pressor tolerance (r = +.32, p < .05), and was β-endorphin concentrations associated with cold pressor tolerance (r = +.33, p<.05). Mediational analyses revealed that higher cortisol levels mediated the relationship between lower ALLO-ir and increased thermal heat pain threshold in the non-Hispanic Whites only. These results suggest that lower ALLO-ir concentrations are associated with decreased pain sensitivity in humans, especially in non-Hispanic Whites, and that this relationship may be mediated by HPA-axis function.","journal":"UNC Libraries","year":2020,"id":144385,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9401,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2020-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":595433,"name":"Beth Mechlin","orcid":null,"position":1,"is_corresponding":false},{"id":130820,"name":"William Maixner","orcid":null,"position":2,"is_corresponding":false},{"id":592324,"name":"A. Leslie Morrow","orcid":"0000-0003-4441-956X","position":3,"is_corresponding":false},{"id":385938,"name":"Susan S. Girdler","orcid":"0000-0002-0190-0938","position":0,"is_corresponding":true}],"reference_count":0,"raw_metadata":null,"created_at":"2026-07-18T23:17:45.339291Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}