Catecholamine Levels in the Guinea Pig Ovary, Myometrium and Costo-uterine Muscle During the Estrous Cycle and in the Ovary Remaining After Unilateral Ovariectomy

Abstract
The levels of norepinephrine in the longitudinal layer of the myometrium, costo-uterine muscle and ovary of the guinea pig have been determined throughout the estrous cycle. Neither the concentration nor the total amount of amine in the ovary or costo-uterine muscle was found to fluctuate systematically during the 15 day cycle of the guinea pigs used. The concentration of norepinephrine was lower in the longitudinal layer of the myometrium when taken from animals in diestrus as compared to those in metestrus. Dopamine was present in ∼10% of the concentration of norepinephrine in the ovary and costo-uterine muscle and in slightly higher proportions in the myometrium.