title: Changes in Purines Concentration in the Cerebrospinal Fluid of Pregnant Women Experiencing Pain During Active Labor.
abstract: Labor pain has been reported as a severe pain and can be considered as a model of acute visceral pain. It is well known that extracellular purines have an important role in pain signaling in the central nervous system. This study analyzes the relationship between extracellular purines and pain perception during active labor. A prospective observational study was performed. Cerebrospinal fluid (CSF) levels of the purines and their metabolites were compared between women at term pregnancy with labor pain (n = 49) and without labor pain (Caesarian section; n = 47). Control groups (healthy men and women without chronic or acute pain-n = 40 and 32, respectively) were also investigated. The CSF levels of adenosine were significantly lower in the labor pain group (P = 0.026) and negatively correlated with pain intensity measured by a visual analogue scale (r = -0.48, P = 0.0005). Interestingly, CSF levels of uric acid were significantly higher in healthy men as compared to women. Additionally, pregnant women showed increased CSF levels of ADP, GDP, adenosine and guanosine and reduced CSF levels of AMP, GTP, and uric acid as compared to non-pregnant women (P < 0.05). These findings suggest that purines, in special the nucleoside adenosine, are associated with pregnancy and labor pain.
authors.affiliation: Department of Biochemistry, Institute of Health Sciences (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil. aschmidt@ufrgs.br.|Department of Anesthesia and Perioperative Medicine, Hospital de Clínicas de Porto Alegre (HCPA), Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil. aschmidt@ufrgs.br.|Division of Anesthesia, Department of Surgery, Federal University of Health Sciences of Porto Alegre (UFCSPA), Porto Alegre, RS, Brazil. aschmidt@ufrgs.br.
authors.forename: André P
authors.initials: AP
authors.lastname: Schmidt
authors.affiliation: Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil.
authors.forename: Ana E
authors.initials: AE
authors.lastname: Böhmer
authors.affiliation: Department of Biochemistry, Institute of Health Sciences (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil.
authors.forename: Gisele
authors.initials: G
authors.lastname: Hansel
authors.affiliation: Department of Biochemistry and Molecular Biology, Federal University of Santa Maria (UFSM), Santa Maria, RS, Brazil.
authors.forename: Félix A
authors.initials: FA
authors.lastname: Soares
authors.affiliation: Programa de Pós-graduação em Saúde e Comportamento, Centro de Ciências da Vida e da Saúde e Hospital Universitário São Francisco de Paula, Universidade Católica de Pelotas, Pelotas, RS, Brazil.
authors.forename: Jean P
authors.initials: JP
authors.lastname: Oses
authors.affiliation: Department of Biochemistry, Institute of Health Sciences (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil.
authors.forename: Alex T
authors.initials: AT
authors.lastname: Giordani
authors.affiliation: Department of Anesthesia and Surgical Intensive Care, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP), São Paulo, SP, Brazil.
authors.forename: Irimar P
authors.initials: IP
authors.lastname: Posso
authors.affiliation: Department of Anesthesia and Surgical Intensive Care, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP), São Paulo, SP, Brazil.
authors.forename: José Otávio C
authors.initials: JO
authors.lastname: Auler
authors.affiliation: Division of Anesthesia, Department of Surgery, Federal University of Health Sciences of Porto Alegre (UFCSPA), Porto Alegre, RS, Brazil.
authors.forename: Florentino F
authors.initials: FF
authors.lastname: Mendes
authors.affiliation: Department of Anesthesia and Perioperative Medicine, Hospital de Clínicas de Porto Alegre (HCPA), Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
authors.forename: Elaine A
authors.initials: EA
authors.lastname: Félix
authors.affiliation: Department of Biochemistry, Institute of Health Sciences (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil.
authors.forename: Luís V
authors.initials: LV
authors.lastname: Portela
authors.affiliation: Department of Biochemistry, Institute of Health Sciences (ICBS), Federal University of Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil.
authors.forename: Diogo O
authors.initials: DO
authors.lastname: Souza
mesh_terms: D000241:Adenosine / Q000134:cerebrospinal fluid; D000244:Adenosine Diphosphate / Q000134:cerebrospinal fluid; D000328:Adult; D002585:Cesarean Section; D005260:Female; D006151:Guanosine / Q000134:cerebrospinal fluid; D006153:Guanosine Diphosphate / Q000134:cerebrospinal fluid; D006801:Humans; D048949:Labor Pain / Q000134:cerebrospinal fluid*; D007743:Labor, Obstetric / Q000134:cerebrospinal fluid*; D008297:Male; D010147:Pain Measurement; D058748:Pain Perception; D011247:Pregnancy; D011446:Prospective Studies; D011687:Purines / Q000134:cerebrospinal fluid*
chemical_list: D011687:Purines; D006151:Guanosine; D006153:Guanosine Diphosphate; D000244:Adenosine Diphosphate; D000241:Adenosine
keywords: Acute pain; Adenosine; Cerebrospinal fluid; Labor pain; Purines; Visceral pain