Patterns of oviducal motility in the cow during the oestrous cycle

Abstract

Microtransducers sensitive to changes in internal diameter were chronically implanted in the oviducts of 5 dairy cows. Motility patterns were recorded throughout 9 oestrous cycles. Cyclic variations in patterns of motility were observed and compared with circulating concentrations of plasma progesterone. Luteal-phase motility patterns were of low amplitude and frequency. The frequency and amplitude of motility increased 3-5 days before behavioural oestrus. This activity consisted primarily of longitudinal muscle contractions, with an interspacing of circular muscle activity occurring during oestrus. Patterns of activity after oestrus were similar to those before oestrus, with activity decreasing 3-5 days after oestrus. Transducers implanted bilaterally in 2 animals permitted observation of asynchronous patterns between right and left oviducts. Preliminary data suggested a higher level of activity in the oviduct ipsilateral to the active ovary. These variations may be due to a local effect, possibly mediated by the functional ovary or the ovum.

In vitro regulation of local secretion and contraction of the bovine oviduct: stimulation by luteinizing hormone, endothelin-1 and prostaglandins, and inhibition by oxytocin

“…In sheep OT is locally recirculated to the oviduct in a higher concentration than is supplied by peripheral blood (Schramm et al 1986) and in women local oviductal tissue levels of OT exceeded its plasma concentrations (Lundin et al 1989). OT increased the contractile activities in the cow oviduct isthmus (Ruckebusch & Bayard 1975, Bennett et al 1988, and oviduct musculature was most sensitive to physiological concentrations of OT at estrus in the ewe (Gilbert et al 1992). Furthermore, the ovine oviduct contains more OT receptors at the postovulatory phase than during the luteal phase (Ayad et al 1991).…”

“…Studies on spontaneous oviduct contraction in the cow revealed low amplitude and frequency motility patterns during the luteal phase (Bennett et al 1988), which gradually increased with the drop in serum progesterone (P 4 ) prior to estrus (Ruckebusch & Bayard 1975). Both amplitude and frequency reach a maximum during estrus, but rapidly diminish over the next 3 days (Ruckebusch & Bayard 1975, Bennett et al 1988).…”

“…Both amplitude and frequency reach a maximum during estrus, but rapidly diminish over the next 3 days (Ruckebusch & Bayard 1975, Bennett et al 1988). The acute withdrawal of endogenous estradiol-17 (E 2 ) has been shown to be a potent stimulus to rabbit oviductal smooth muscle and contributes to an increase in muscular activity at ovulation (Halbert & Conrad 1975).…”

Angiotensin II Secretion by the Bovine Oviduct is Stimulated by Luteinizing Hormone and Ovarian Steroids

“…Estrous cycle-dependent oviductal contractile patterns appear to be attributed to these timely movements of gametes and embryos. Studies of spontaneous oviductal contractile patterns in the cow have revealed that the amplitude and frequency of contractions are low during the luteal phase [1], and a gradual increase in contractile amplitude and frequency ouccrs concomitant with a rapid decrease in the progesterone (P4) level [2]. Both contractile amplitude and frequency reach their maximal values during estrus, and the values quickly diminish over the next 3 days [1,2].…”

“…Studies of spontaneous oviductal contractile patterns in the cow have revealed that the amplitude and frequency of contractions are low during the luteal phase [1], and a gradual increase in contractile amplitude and frequency ouccrs concomitant with a rapid decrease in the progesterone (P4) level [2]. Both contractile amplitude and frequency reach their maximal values during estrus, and the values quickly diminish over the next 3 days [1,2].Angiotensin (Ang) II, the major bioactive peptide of the reninangiotensin system, is involved in autocrine/paracrine regulation of the oviduct [3]. It is a vasoactive peptide that is converted from Ang I by angiotensin-converting enzyme-1 (ACE-1).…”