title: The effect of labetalol on urinary prostacyclin secretion during surgery.
abstract: The effects of labetalol on the secretion of prostacyclin and plasma-renin activity (PRA) were evaluated, relative to a control group in 24 patients undergoing hip osteotomy. They were randomly assigned to two groups (G-I and G-II) with 12 patients each. Patients allocated to both groups received standard anaesthesia (thiopentone, pancuronium, fentanyl and nitrous oxide). Patients belonging to Group II were given labetalol at a dose of 0.8 mg kg-1. The stable metabolite of PGI2, 6-keto-PGF1 alpha was quantified from urine samples by radioimmunoassay (RIA). Cortisol, PRA and aldosterone were determined from blood samples. A significant increase in 6-keto-PGF1 alpha elimination was observed in G-I. Labetalol administration partially but significantly inhibited this increase. We believe that prostacyclin is involved not through the beta 1 but through the alpha 1 receptors in the secretion of renin.
mesh_terms: D015121:6-Ketoprostaglandin F1 alpha / Q000652:urine; D000328:Adult; D011464:Epoprostenol / Q000652:urine*; D005283:Fentanyl; D006621:Hip Joint / Q000601:surgery; D006801:Humans; D007432:Intraoperative Period; D007741:Labetalol; D008875:Middle Aged; D009609:Nitrous Oxide; D010027:Osteotomy; D010197:Pancuronium; D012084:Renin-Angiotensin System / Q000187:drug effects; D013874:Thiopental
chemical_list: D015121:6-Ketoprostaglandin F1 alpha; D011464:Epoprostenol; D010197:Pancuronium; D013874:Thiopental; D009609:Nitrous Oxide; D007741:Labetalol; D005283:Fentanyl