Synergistic relaxing effect of the paracetamol and pyrilamine combination in isolated human myometrium

Mario I Ortiz; Mario I. Ortíz; Héctor Ponce‐Monter; Héctor A Ponce-Monter; José A. Mora-Rodríguez; Guillermo Barragán‐Ramírez; Guillermo Barragán-Ramírez; Bertha S. Barrón-Guerrero

doi:10.1016/j.ejogrb.2011.02.011

Synergistic relaxing effect of the paracetamol and pyrilamine combination in isolated human myometrium

Mario I Ortiz, Mario I. Ortíz, Héctor Ponce‐Monter, Héctor A Ponce-Monter, José A. Mora-Rodríguez, Guillermo Barragán‐Ramírez, Guillermo Barragán-Ramírez, Bertha S. Barrón-Guerrero

European journal of obstetrics, gynecology, and reproductive biology · 2011 · vol. 157(1) , pp. 22–26 · doi:10.1016/j.ejogrb.2011.02.011 · PMID:21439705 · W2064195006

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This study investigated the synergistic relaxing effect of paracetamol and pyrilamine on isolated human myometrium, finding a combined relaxation effect.

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Abstract

OBJECTIVE: To evaluate the interaction type of the human uterine relaxant effect of the paracetamol-pyrilamine combination (PPC) in vitro. STUDY DESIGN: Uterine strips were contracted with KCl (60 mM) and treated with vehicle or increasing concentrations of paracetamol (100-3200 μM), pyrilamine (3.2-100 μM) or the PPC. The relaxing effects of the drugs alone and in combination were measured. Isobolographic analysis was used to determine the pharmacologic interaction type. RESULTS: Paracetamol, pyrilamine and the PPC produced a significant relaxing effect on non-pregnant human uterine strips pre-contracted with KCl (60 mM). The EC30 values for paracetamol and pyrilamine on the uterine contraction were 2391.3±595.3 μM and 14.7±1.7 μM, respectively. The derived experimental EC30 for the PPC was 401.8±129.8 μM. This value was significantly lower (p<0.05) than the theoretical EC30 expected for a purely additive interaction, which was 1203.0±297.7 μM for the PPC. The interaction index (γ) was 0.33±0.14 for PPC, being statistically different from unity. CONCLUSION: Data suggest that low doses of the PPC can interact synergistically and therefore this drug association may represent a therapeutic advantage for the clinical treatment of dysmenorreic pain.

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MeSH descriptors

Acetaminophen Analgesics, Non-Narcotic Histamine H1 Antagonists Muscle Relaxation Myometrium Pyrilamine Acetaminophen Adult Analgesics, Non-Narcotic Data Interpretation, Statistical Drug Synergism Dysmenorrhea Dysmenorrhea Female Histamine H1 Antagonists Humans In Vitro Techniques Middle Aged Muscle Relaxation Myometrium

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Cites (4)

References (33)

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SciLite annotations

chemicals 9

paracetamol phenylethylamine paracetamol phenylethylamine paracetamol paracetamol phenylethylamine paracetamol phenylethylamine

organisms 3

human human human

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[1] Dysmenorrhea in adolescents and young adults: etiology and management 2006

[2] Dysmenorrhea in adolescents: diagnosis and treatment 2008

[3] A comparative study of ibuprofen and paracetamol in primary dysmenorrhea. 1974

[4] Prostaglandins, prostaglandin inhibitors and their roles in gynaecological disorders 1992