STM Article Repository

Enhanced stimulation of bladder and prostatic α1-adrenoreceptors (α1-ADR) triggers lower urinary tract symptoms. Phenylephrine (PHE) induces α1-ADR-mediated smooth muscle contractions In vitro and urodynamic dysfunction in rats. Extracts from saw palmetto and Roystonea regia fruits antagonize α1-ADR responses. Effects of Acrocomia crispa (AC), an endemic Cuban palm, are unexplored. This study investigates the effects of D-005, a lipid extract of AC fruits, on PHE-induced contractions in vas deferens and PHE-induced contractions urodynamic dysfunction in rats. In vitro study: Preparations of rat vas deferens were incubated with Tyrode´s solution (control), tamsulosin 0.1 mg/mL or D-005 (125-500 mg/mL). Contractions were induced with PHE (1 x10-6 - 3x10-4 mol/L) or KCl (50 mmol/L). In vivo study: Rats were randomized into a negative vehicle control and seven PHE (5 mg/kg)-injected groups: positive control, D-005 (5, 25, 50, 200, 400 mg/kg) and tamsulosin (0.4 mg/kg). Volume voided per micturition (VM) and urinary total volumes (UTV) were measured. Tamsulosin inhibited PHE-induced contractions and did not change KCl-induced contractions. D-005 (250 and 500 μg/mL, not 125 mg/mL) inhibited significantly and markedly contractions to all PHE concentrations and modestly KCl-induced contractions. PHE lowered significantly VM and UTV in positive controls versus the negative control group. Tamsulosin increased VM (78%) and UTV (78%) versus the positive control group. D-005 (25 - 800 mg/kg, not 5 mg/kg) increased significantly and dose dependently VM versus the positive control. All doses increased significantly UTV. In conclusion, D-005 inhibited PHE-induced contractions in vas deferens of rats and ameliorated PHE-induced urodynamic dysfunction in rats, thus antagonizing α1-ADR-mediated responses.