The effect of adrenaline, noradrenaline and isoprenaline on the guinea-pig uterus.
The actions of adrenaline, noradrenaline and isoprenaline were compared on the isolated guinea-pig uterus. In uteri from immature animals (200 to 350 g) adrenaline caused relaxation which changed to a biphasic effect and finally to a contraction in the course of an experiment (6 to 8 hr). Noradrenaline always caused contraction and isoprenaline relaxation. In uteri from oestrogen-treated animals adrenaline and noradrenaline caused contraction and isoprenaline caused relaxation. Isoprenaline potentiated the contraction produced by adrenaline and reversed the adrenaline relaxation to a contraction. The change of the pharmacological action of adrenaline was not related to the Na(+) and K(+) content of the uterus, which remained constant throughout an experiment involving repeated application of the amines. Nor could it be related to a change in the glycogenolytic effect of adrenaline estimated by determinations of total glycogen of the muscle which, however, may not reflect a momentary change in rate of breakdown.
D000588:Amines; D000818:Animals; D002395:Catecholamines / Q000494:pharmacology*; D004837:Epinephrine; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D007545:Isoproterenol; D009638:Norepinephrine; D012964:Sodium; D014599:Uterus / Q000494:pharmacology*
D000588:Amines; D002395:Catecholamines; D012964:Sodium; D007545:Isoproterenol; D009638:Norepinephrine; D004837:Epinephrine
CATECHOLAMINES/pharmacology; UTERUS/pharmacology