Motor activity of the human Fallopian tube in vitro in relation to plasma concentration of oestradiol and progesterone, and the influence of noradrenaline

Abstract

The contractile pattern of the human Fallopian tube was studied in preparations from the ampullary and isthmic regions mounted in an organ bath for measurement of longitudinal and circular smooth muscle activity. The material was obtained during the follicular, ovulatory, and luteal phases of the cycle as defined primarily from plasma oestrogen and progesterone values. The frequency of the spontaneous contractions increased progressively during the follicular phase to become maximal around ovulation. There was no consistent difference between isthmus and ampulla; the circular musculature had a higher frequency than the longitudinal during the ovulatory phase. Noradrenaline (3 x 10(-6) M) in general potentiated the difference in frequency seen between the ovulatory phase on the one hand and the follicular and luteal phases on the other. Contractile activity, assessed by planimetric integration of the curve on the pen-recorder trace, increased markedly during the ovulatory phase in all types of smooth muscle preparations. Exogenous noradrenaline inhibited spontaneous motor activity in preparations from pregnant or post-menopausal women or from women taking combined-type oral contraceptives. This effect was most marked in the circular muscle. Thus the different regions of the human Fallopian tube in vitro show various patterns of spontaneous motor activity in relation to the plasma steroid concentrations furing the menstrual cycle. Responses to exogenous noradrenaline also varied, indicating that the effects of endogenous noradrenaline released from sympathetic nerves may vary similarly.

The Octopamine Receptor OAMB Mediates Ovulation via Ca2+/Calmodulin-Dependent Protein Kinase II in the Drosophila Oviduct Epithelium

“…Moreover, norepinephrine levels in the human fallopian tube vary in a region- and estrous cycle-dependent manner being the highest in the isthmus and the fimbriated end at the time of ovulation [37]. When assayed in vitro , adrenergic receptor agonists not only modulate oviduct muscle activities [38], [39] but they also stimulate fluid secretion possibly via Ca 2+ -dependent mechanisms [33], [40]. Oviduct fluid in mammals is critical for egg transport, maturation and fertilization; however, the cellular process regulating its secretion is largely unknown.…”

Quantitative pharmacological characterization of β‐receptors and two types of α‐receptors mediating sympathomimetic smooth muscle response in the human Fallopian tube at various cyclic stages

“…T h e sympathomimetic response is changed during the menstrual cycle, conceivably reflecting a n altered balance between aand p-adrenoceptor function . Owman et al 1976. Helm et at.…”

“…1 9 8 1~) . Also the sympathomimetic response of the tubal smooth muscle changes markedly with the levels of estradiol and progesterone , Owman et al 1976, Lindblom et al 1980, Helm et al 1981d). This does not seem to be a simple relationship to the plasma levels of the two steroids, but rather to their tissue/plasma ratio as a reflection of steroid receptor activity (Batra et al 1980, Helm et al 19814.…”

The Critical Roles of Progesterone Receptor (PGR) in Ovulation, Oocyte Developmental Competence and Oviductal Transport in Mammalian Reproduction

“…These changes are coordinated by ovarian steroids, with E2 resulting in muscular contraction and high levels of P4 or progestagens promoting relaxation (Wanggren et al. 2006, 2008; Helm et al. 1982).…”