title: Failure of the oxytocin-induced increase in secretion of urinary kallikrein in young spontaneously hypertensive rats.
abstract: Urinary kallikrein excretion during oxytocin (OT) infusion were studied in anesthetized (sodium pentobarbital, 50 mg/kg, i.p.) young (4-weeks-old) spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). OT-infusion (30 nmol/kg/30 min) to WKY significantly increased urinary excretion of the active kallikrein from the basal levels (25.4 +/- 5.6 10(-2) x AU/15 min, n = 5) to 37.3 +/- 5.0 10(-2) x AU/15 min (P < 0.05, n = 5) and 50.7 +/- 17.1 10(-2) x AU/15 min (P < 0.05, n = 5) 15 and 30 min after the start of OT-infusion, respectively. In SHR, OT-infusion did not increase the urinary excretion of active kallikrein, but did decrease the urine volume and sodium excretion. The concentration of the active kallikrein in the kidney of WKY was not changed by OT-infusion, but that of SHR was slightly increased. The OT-infusion resulted in significantly higher concentrations of the active kallikrein in SHR kidney than in WKY kidney. These results suggest that less excretion of urinary kallikrein in SHR during OT-infusion may be attributable to a lower response in the secretion of kallikrein from the kidney.
authors.affiliation: Department of Pharmacology, Kitasato University School of Medicine, Kanagawa, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Majima
authors.forename: K
authors.initials: K
authors.lastname: Adachi
authors.forename: T
authors.initials: T
authors.lastname: Ohno
authors.forename: M
authors.initials: M
authors.lastname: Ogino
authors.forename: M
authors.initials: M
authors.lastname: Saito
authors.forename: K
authors.initials: K
authors.lastname: Kizuki
authors.forename: O
authors.initials: O
authors.lastname: Katsumata
authors.forename: S
authors.initials: S
authors.lastname: Yamashina
authors.forename: M
authors.initials: M
authors.lastname: Katori
mesh_terms: D000818:Animals; D015153:Blotting, Western; D001920:Bradykinin / Q000031:analogs & derivatives / Q000494:pharmacology; D065168:Bradykinin Receptor Antagonists; D007610:Kallikreins / Q000652:urine*; D007668:Kidney / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D010121:Oxytocin / Q000494:pharmacology*; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY
chemical_list: D065168:Bradykinin Receptor Antagonists; D010121:Oxytocin; C065679:icatibant; D007610:Kallikreins; D001920:Bradykinin