Uterine Catheters Research Articles

An anaesthetic technique for implanting fetal and uterine catheters in pregnant pony mares : P.M. Taylor a, M. Silver and A. Fowden, Physiological Laboratory, University of Cambridge, U.K. and aAnimal Health Trust, Newmarket, U.K.

An anaesthetic technique for implanting fetal and uterine catheters in pregnant pony mares : P.M. Taylor a, M. Silver and A. Fowden, Physiological Laboratory, University of Cambridge, U.K. and aAnimal Health Trust, Newmarket, U.K.

Reproductive anatomy, manipulation of ovarian activity and non-surgical embryo recovery in suni (Neotragus moschatus zuluensis)

Marked disparity in the uterine horn dimensions and relative degrees of caruncle development in suni suggested that exclusive or predominant dextral implantation occurs in association with bilateral ovulatory activity. Daily urinary measurements of pregnanediol-3 alpha-glucuronide revealed an oestrous cycle of approximately 21 days in length. Ovarian activity was controlled for synchronization of oestrus by using progestagen-impregnated intravaginal sponges and multiple ovulations were induced by using exogenous gonadotrophin therapy. An effective transcervical uterine catheterization technique was developed for the non-surgical collection of embryos. The efficiency of embryo recovery performed 5 days after sponge removal was 50.0%.

Detection of a progesterone-dependent secretory protein synthesized by cat endometrium.

Uterine flushings and culture media from endometrial explants incubated in the presence of radiolabeled amino acids were analyzed using one-(1-D) and two-dimensional (2-D) gel electrophoresis to identify proteins synthesized by the endometrium and subsequently released into the uterine lumen. 1-D and 2-D analyses of uterine flushings and culture media of endometrial explants obtained from 7- to 11-day pregnant cats (pre-implantation) showed a Mr 30,000 protein that appeared on 2-D gels as a family of macromolecules with isoelectric points between 6.5 and 7.0. This family of macromolecules was also present in the culture media of implantation-site tissue obtained from 12- to 16-day pregnant cats and of nonimplantation-site endometrium obtained form 12- to 28-day pregnant cats. The Mr 30,000 protein was absent in uterine flushings and culture media from estrous and 3- to 5-day-pregnant cats. In ovariectomized, steroid-treated animals, the Mr 30,000 protein was only detected in flushings and media from those animals treated with progesterone, regardless of the presence or absence of estradiol-priming and/or simultaneous estradiol treatment. In daily flushings obtained from ovariectomized, steroid-treated cats equipped with an indwelling uterine catheter, the Mr 30,000 protein was absent during the 14 days of estradiol treatment and was first detected 3-4 days after the onset of estradiol plus progesterone treatment. This protein was not detected in serum from estrous, 9-day pregnant, ovariectomized, and ovariectomized, steroid-treated animals. This study shows that 1) a progesterone-dependent protein, with an approximate molecular weight of 30,000 and an isoelectric point of 6.5-7.0, first appears within the uterine lumen soon after the arrival of the blastocyst and continues to be present during implantation; 2) the synthesis and release of the Mr 30,000 protein is dependent on progesterone regardless of the presence or absence of estradiol; and 3) the onset of secretion of the Mr 30,000 protein requires 3-4 days of continuous progesterone treatment in the estradiol-primed cat.

Prolongation of the luteal phase by prostaglandin E 2 during the estrous cycle in the cow. A preliminary report

An experiment was conducted to determine the effects of prostaglandin E 2 (PGE 2) on ovarian progesterone secretion during the estrous cycle in the cow. Intraluminal uterine catheters were implanted in three beef cows (2 treated, 1 control), and 1.3 mg of PGE 2 were infused into the uterus every 4 hours from days 9 through 21 post-estrus. Blood samples were collected from the jugular vein at 2-hour intervals from days 9 to 21 and twice daily from day 22 to 28 post-estrus. Progesterone was measured by applying a specific, direct plasma radioimmunoassay in all samples without extraction. Intrauterine infusion with PGE 2 resulted in maintenance of luteal-phase progesterone secretion until day 21 post-estrus, 4 days after luteal regression occurred in the vehicle-treated cow. In this study, we demonstrated that PGE 2 can prolong the presence of luteal phase plasma progesterone concentrations by possibly stimulating in vivo steroidogenesis by the corpus luteum during the estrous cycle in the cow.

Induction and inhibition of uterine vasodilation by catechol estrogen in oophorectomized, nonpregnant ewes.

The biological activity of the catechol estrogens remains in question. The effect of these substances on uterine blood flow, another measure of estrogenicity, has not been evaluated. In this investigation we studied the effect of catechol estrogens on uterine blood flow in six chronically instrumented, oophorectomized, nonpregnant ewes. Electromagnetic flow probes were implanted around the main uterine arteries and catheters were placed in distal branches of the uterine arteries to provide direct access to the uterine circulation. Dose-response curves were constructed that described the magnitude of estrogen- induced uterine vasodilation after the local, intraarterial infusion of 17β-estradiol (E2), estrone (E1), 2-hydroxyestradiol (2-OHE2), and 2-hydroxyestrone (2-OHE1). Significant increases in uterine blood flow were observed after the infusion of each estrogen. The order of potency was E2 > E1 > 2-OHE2 > 2- OHE1; the doses of 2-OHE2 and 2-OHE1 necessary to obtain a response comparable to that seen wit...

Unsuccessful attempts to collect ova by surgical fixation of uterine catheters in superovulated cows.

Attempts were made to collect ova from superovulated cows by surgically fixing indwelling silastic balloon catheters in the uterine lumen. No ova were collected from the four catheterised cows and it was shown that ovarian activity was depressed. In this group, only 16 ovulations occurred compared with six control cows in which a total of 121 ovulations were recorded and 84 ova were collected. Also the ovaries of the catheterised cows had six large cysts, whereas no cysts were recorded in the control cows. The catheters flushed perfectly and bacteriological cultures of the flushing and uteri showed that no infections had occurred. The cows tolerated the catheters extremely well. There was no depression in appetite nor was any abnormal behaviour recorded. However, the severe depression of ovulation and the formation of ovarian cystic follicles prevents the technique from having any practical application as a means of collecting ova.

Dosimetry of cathetron applicators in intracavitary therapy.

Theoretical computations have been done to obtain dose distributions in the paracervical and sagittal planes for various loadings of Cathetron applicators. Uterine catheters of various sizes and shapes and various loadings of ovoid catheters have been considered for the dosimetry. Experimental measurements have been made to verify the computed dose distributions. The computed dose distributions have also been compared with those of a conventional Manchester loading. Although the ratio of dose contribution to point A from vaginal sources to that from the uterine sources is found to be significantly different for Cathetron therapy from the conventional Manchester system, the isodose distributions in the paracervical plane are in good agreement. However, the differences in the isodose distributions in the sagittal plane indicates a higher dose to the rectal region for Cathetron therapy, which can be reduced by the use of rectal retractors.

Some physiological changes in pregnant sheep and goats before, during and after surgical insertion of uterine catheters

Corticosteroid concentrations in maternal plasma from pregnant sheep and goats increased during the preoperative starvation period, anaesthesia and surgery, and reached maximum values when the animals regained consciousness. During the operation the vaginal temperature fell 2-3 degrees C. Postoperatively, corticosteroid levels took two to four days, while glucose concentrations took five to seven days in sheep and 10-12 days in goats to return to prestarvation levels. Feed intakes returned to prestarvation levles three to four days after operation in sheep and five to seven days after operation in goats.

Water vacuum suction curettage (WVSC) for late first trimester abortions

Water vacuum suction curettage (WVSC) has been shown to be an effective method for elective abortions to 10 weeks' gestation. Application of this modality of suction for late first trimester gestations (10 to 12 weeks), however, remains conjectural, thus providing the basis for the present study. Sixty patients from 10 to 12 weeks' gestation underwent WVSC following cervical dilatation and the use of standard uterine catheters. The results confirm the extended use of this method of suction curettage for late first trimester abortions, thereby giving an extra dimension of safety to its use.

Effects of a progestin on parturition and the post-partum period in pigs

Delay of parturition was intended in 30 sows fed daily 30 mg (14) or 50 mg (16) of chlormadinone acetate (CAP) from Day 108 until parturition. Thirty untreated sows served as controls. Neither doese delayed parturition, since all sows farrowed on Day 114 or 115, but caused significant dose-related increase in dystocias and the frequency of stillbirths. Experiments in two sows with open intraluminal uterine catheters, for the recording of myometrium activities and related intraluminal pressure during parturition, revealed that after 6 days of premedication with 30 mg CAP, typical uterine pressure waves were absent. The amplitude of remaining atypical pressure waves was reduced by about 50 %, but their duration was increased. In CAP-treated animals, post-partum metritis and agalactia were markedly reduced.

Transcervical uterine catheterization in rhesus monkeys

A technique for inserting catheters and other materials into the uterine cavity of rhesus monkeys, per vaginam, with minimal trauma, has been described. Some applications of the technique are given.