Concentrations Of Prostaglandin F2 Alpha Research Articles

The Effects of Saturated and Polyunsaturated Fatty Acids on Reproductive Performance and Reproductive Hormonal Changes in Dairy Cows at the Transition Period

Reproductive success is crucial in dairy farming as it heavily relies on the consumption of a complete mixed ration for the diet. The current study investigated the effects of adding saturated (SFA) and polyunsaturated fatty acids (PUFAs) to dairy cows' diets on reproductive performance and reproductive hormones during the transition period. A total of 30 Holstein dairy cows were randomly divided into three groups (10 animals in each group), based on parity and body condition score. The cows had an initial body weight of 567.5 ± 40.3 kg (mean ± SD), a body condition score of 3.5 ± 0.26 out of 5 (mean ± SD), and a parity of 1.7 ± 0.02 (mean ± SD). The control group received a balanced ration meeting all the nutrient requirements according to the National Research Council (NRC) guidelines. The SFA group received 1.4% of dry matter (DM) as palm oil (RumiFat®), while the omega group had 5% of DM as safflower (a source of n-6 fatty acids) added from 21 days before parturition to 21 days after, and 4% of DM as flaxseed (a source of n-3 fatty acids) added from 21 to 42 days after parturition. In the Omega group, estradiol concentration significantly increased on artificial insemination (AI) day (12.54 pg/mL). Additionally, serum prostaglandin F2-alpha concentration was significantly higher in the omega group (0.732 pg/mL on day 7 and 1.68 pg/mL on day 14) compared to other groups. The control group exhibited the highest progesterone concentrations at 14 and 21 days post-calving compared to the other groups, other groups. whereas the omega group highest concentration five days after AI. The omega group also showed a significantly higher mean number of follicles >10mm and larger ovulatory follicle diameter. Moreover, a higher percentage of pregnant cows at 120 days in milk, fewer open days, and lower service per conception were observed in the omega group compared to the other groups. In conclusion, supplementing dairy cows' diets with PUFAs during the transition period positively influenced ovarian function, hormone levels, and reproductive performance.

PGF<sub>2α</sub> induced estrus synchronization of native buffaloes in Bangladesh

Buffaloes have low fertility due to silent estrus, seasonal anestrous, delayed puberty and long calving interval. This study was aimed to investigate the effect of single and double doses of prostaglandin F2alpha (PGF2a) on synchronization of estrus in buffaloes. A total of 66 buffaloes were selected and subjected to estrus synchronization experiments: single dose PGF2a, and double dose PGF2a. In single dose PGF2a experiment, buffaloes were injected with either 500 or 875 µg of cloprostenol (PGF2a) and all buffaloes were examined to identify corpus luteum through rectal palpation before administration of PGF2a. In double dose experiment, buffaloes were injected with either 500 or 875 µg of cloprostenol (PGF2a) on Day 0 and Day 12 without identifying corpus luteum. The buffaloes were examined for estrus by collecting cervical mucus using universal artificial insemination gun from the mid cervix and timed artificial inseminations (TAI) were done after 72 hrs of last dose of PGF2α injection. The results showed that there were no significant differences in estrus rate (75±3.96% and 85±0.79%) single dose of PGF2α with 500 and 875 µg of cloprostenol, respectively. However, 875 µg of cloprostenol significantly (P<0.05) increased estrus rate in buffaloes than double doses with 500 and 875 µg of cloprostenol (60 ± 12.72% and 63 ± 2.22%). The conception rate in buffaloes were 45±6.91% and 55±6.91% in 500 µg and 875 µg of cloprostenol in single dose of PGF2a and 30±14.69% and 37±8.81% in 500 µg and 875 µg of cloprostenol in double dose of PGF2a. The calving rate in buffaloes were 10±5.20% and 15±0.79% in 500 µg and 875 µg of cloprostenol in single dose of PGF2a and 10±8.33 and 12±6.18% in 500 µg and 875 µg of cloprostenol in double dose of PGF2a. However, there were no significant differences in conception and calving rates in buffaloes neither between single and double doses PGF2a nor different concentrations of PGF2a. In conclusion, single dose of PGF2a with 875 µg of cloprostenol injection efficiently increased estrus synchronization rate in buffaloes.
 Bang. J. Anim. Sci. 2021. 50 (2): 80-85

Effect of natural pre-luteolytic prostaglandin F2α pulses on the bovine luteal transcriptome during spontaneous luteal regression†.

The pulsatile pattern of prostaglandin F2alpha (PGF) secretion during spontaneous luteolysis is well documented, with multiple pulses of exogenous PGF necessary to induce regression using physiologic concentrations of PGF. However, during spontaneous regression, the earliest pulses of PGF are small and not associated with detectable changes in circulating progesterone (P4), bringing into question what, if any, role these early, subluteolytic PGF pulses have during physiologic regression. To investigate the effect of small PGF pulses, luteal biopsies were collected throughout natural luteolysis in conjunction with bihourly blood samples to determine circulating P4 and PGF metabolite to retrospectively assign biopsies to early and later regression. Whole transcriptome analysis was conducted on CL biopsies. Early PGF pulses altered the luteal transcriptome, inducing differential expression of 210 genes (Q < 0.05) during early regression, compared with 4615 differentially expressed genes during later regression. In early regression, few of these differentially expressed genes were directly associated with luteolysis, rather there were changes in local steroid and glutathione metabolism. Most (94%) differentially expressed genes from early regression were also differentially expressed during later regression, with 98% of these continuing to be altered in the same direction compared with CL at a similar stage of the cycle that had not yet been exposed to PGF. Thus, early, subluteolytic PGF pulses impact the luteal transcriptome, though not by altering steroidogenesis or causing direct inhibition of cellular function. Rather, small pulses alter pathways resulting in the removal of cellular support systems, which may sensitize the CL to later pulses of PGF.

Changes in the expression of prostaglandin family members in bovine corpus luteum during the estrous cycle and pregnancy.

The aim of this study was to characterize certain prostaglandin family members in the bovine corpus luteum (CL) during the estrous cycle and pregnancy. The CL tissue was assigned to thestages 1-2, 3-4, 5-7, 8-12, 13-16 and >18 days (after regression) of the estrous cycle and1-2, 3-4, 6-7, and >8 monthsof pregnancy. In these samples, we investigated prostaglandin F2alpha (PTGF), prostaglandin E2 (PTGE), their receptors (PTGFR, PTGER2, and PTGER4), cyclooxygenase 2 (COX-2), PTGF synthase (PTGFS), and PTGE synthase (PTGES). The expression of messenger RNA (mRNA) was measured by reverse transcription quantitative polymerase chain reaction, hormones by enzyme immunoassay, and localization by immunohistochemistry. The mRNA expression of COX-2, PTGFS, and PTGES in CL during the early-luteal phase was high followed by a continuous and significant downregulation afterward, as well as during all phases of pregnancy. The concentration of PTGF in CL tissue was high during the early-luteal phase, decreased significantly in the mid-luteal phase, and increased again afterward. In contrast, the concentration of PTGE increased significantly during the late-luteal phase followed by a decrease during regression. The PTGE level increased again during late pregnancy. Immunohistochemically, the large granulose-luteal cells show strong staining for COX-2 and PTGES during the early-luteal stage followed by lower activity afterward. During pregnancy, most of the luteal cells were only weakly positive or negative. In conclusion, our results indicate that the examined prostaglandin family members are involved in the local mechanisms that regulate luteal function, specifically during CL formation, function, and regression and during pregnancy in the cow.

Plasma Clearance and Half-Life of Prostaglandin F2alpha: A Comparison Between Mares and Heifers1

Horses are about five times more sensitive to the luteolytic effect of prostaglandin F2alpha (PGF) than cattle, as indicated by a recommended clinical dose of 5 mg in horses and 25 mg in cattle. Novel evaluations of the PGF plasma disappearance curves were made in mares and in heifers, and the two species were compared. Mares and heifers (n = 5) of similar body weight were injected (Min 0) intravenously with PGF (5 mg per animal). Blood was sampled every 10 sec until Min 3, every 30 sec until Min 5, every 10 min until Min 60, and every 30 min until Min 240. The mean PGF concentration was greater (P < 0.05) in mares than in heifers at Min 1 through Min 60 and at Mins 180 and 240. The mean time to maximum PGF concentration was not different between mares (42.0 ± 8.6 sec) and heifers (35.0 ± 2.9 sec). The apparent plasma clearance, distribution half-life, elimination half-life, and maximum plasma PGF concentration were 3.3 ± 0.5 L h(-1) kg(-1), 94.2 ± 15.9 sec, 25.9 ± 5.0 min, and 249.1 ± 36.8 ng/ml, respectively, in mares and 15.4 ± 2.3 L h(-1) kg(-1), 29.2 ± 3.9 sec, 9.0 ± 0.9 min, and 51.4 ± 22.6 ng/ml, respectively, in heifers. Plasma clearance was about five times less (P < 0.0005), maximum plasma PGF concentration was five times greater (P < 0.002), and the distribution half-life and elimination half-life were about three times longer (P < 0.005) in mares than in heifers. The fivefold greater plasma clearance of PGF in heifers than in mares corresponds to the recommended fivefold greater clinical dose of PGF in cattle and supported the hypothesis that the metabolic clearance of PGF is slower in mares than heifers.

Relationship between infection, inflammation and premature parturition in mares with experimentally induced placentitis

Ascending placentitis results in premature birth and high foal mortality. By understanding how placentitis induces premature delivery, it may be possible to develop diagnostic markers and to delay premature delivery pharmacologically, thereby decreasing perinatal foal mortality. To identify relationships between bacterial infection, inflammation and premature parturition in mares with experimentally induced placentitis. Experiment 1: Concentrations of allantoic fluid prostaglandins (PGs) F2alpha and E2 were measured in 8 mares after intracervical inoculation with Streptococcus equi ssp. zooepidemicus (at Days 285-291 of gestation) until parturition and compared with controls (n = 4). Experiment 2: mRNA expression of interleukin (IL)-1beta, IL-6, tumour necrosis factor (TNF)-alpha and IL-8 in the chorioallantois from inoculated mares in Experiment 1 were compared with 7 mares that foaled normally. Bacterial inoculation resulted in 7 aborted fetuses and birth of one premature, viable foal. Infection was associated with inflammation of the chorioallantois in the region of the cervical star, isolation of bacteria and high concentrations of PGE2 and PGF2alpha in allantoic fluid obtained within 48 h of delivery (P = 0.04). Chorioallantois from all mares expressed mRNA for IL-8, TNF-alpha, IL-6 and IL-1beta. Experimentally infected mares expressed more mRNA for IL-6 (P = 0.003) and IL-8 (P = 0.009) in the cervical star region and more mRNA for IL-6 (P = 0.004) in tissues from placental horns than control mares. Bacterial placentitis may result in liberation of cytokines from the chorioallantois and prostaglandin formation leading to abortion or birth of a precociously mature foal.

Selective Increased Luteal Prostaglandin E2 Compared to F2 Alpha Biosynthesis and Signaling Are Critical for Luteal Protection and Resistance During Establishment of Pregnancy in Sheep.

In ruminants, pulsatile secretion of prostaglandin F2 alpha (PGF2a) by the endometrium is locally transported to corpus luteum (CL) and stimulates intraluteal PGF2a biosynthesis and induces luteal regression/luteolysis. Interestinlgy, luteolytic PGF2a fails to accomplish regression of CL of early pregnancy. This increased resistance of the CL to PGF2a may suggest existence of luteal protective mechanisms. Early physiological studies proposed prostaglandin (E2) PGE2 as luteal protective mediator because PGE2 counteracted the effects of PGF2a and protected the CL from regression. However, the molecular and cellular aspects of resistance of the CL to luteolytic PGF2a are largely unknown. The objective of this study is to determine biosynthesis, transport, and signaling of PGF2a and PGE2 in CL during the estrous cycle and early pregnancy in sheep. Suffolk cross-bred ewes were ovariohysterectomized on days 12, 14 and 16 of the estrous cycle (ECY) or pregnancy (PNY), the CLs were collected, and temporal expression of PGF2a and PGE2 biosynthetic, transport and signaling proteins were determiend by western blot. Blood samples were collected from the ovarian artery and ovarian vein and transport of PGF2a, PGFM, PGE2, and PGEM were determiend by ELISA. Results indicated that: (i) COX-2 protein was abundantly expressed on days 12-16 of ECY and PNY and not affected by the ECY or PNY status, and COX-1 protein was expressed at very low level; (ii) PGES-1 protein was abundantly expressed on days 12-14 of ECY and PNY, and then decreased (4 fold) on day 16 of the ECY compared to that of PNY, expression of PGES-2 protein was not modulated by ECY and PNY, and expression of PGES-3 protein was decreased (5 fold) on days 12-16 of ECY compared to that of PNY; (iii) expression of PGFS-AKR1C1 protein was not modulated by ECY and PNY, and PGFS-AKR1C3 protein was expressed at steady sate level on day 10-16 of ECY but decreased (several fold) on days 12-16 of PNY; (iv) expression of FP, EP1 and EP3 proteins were not modulated by ECY and PNY, but interestingly, expression of EP2 and EP4 proteins were decreased (4 fold) on day 16 of ECY compared to that of PNY; (v) PGT protein was abundantly expressed on days 12-16 of ECY and PNY and its expression was decreased on day 16 of ECY compared to that of PNY; and (vi) PGDH protein expression was increased on days 14-16 of PNY compared to that of ECY. (vi) Ovarian venous plasma concentrations of PGF2a, PGFM, PGE2 and PGEM were 1500-2000 pg/ml, 400-500 pg/ml, 1000-1250 pg/ml, and 2-5 pg/ml on days 14-16 of the estrous cycle, respectively, and 400-500 pg/ml, 2000-2500 pg/ml, 3000-3500 pg/ml, and 3-5 pg/ml on days 14-16 of pregnancy, respectively. These results together suggest that the luteal PG biosynthetic and signaling machinery is selectively directed towards PGF2a at the time of luteolysis, by contrast; towards PGE2 at the time of establishment of pregnancy. In addition, CL of pregnancy has innate capacity to catabolize PGF2 to inactive PGFM but not PGE2 to PGEM and favors intraluteal PGE2 production. Thus, increased intraluteal PGE2 production and action are the critical mechanisms that resist/protect CL of early pregnancy to luteolytic PGF2a. Selective inhibition of PGES-1 or EP2 and EP4 along with PGF2a could be the potential future therapeutic strategy to improve reproductive efficiency in ruminants. Supported by USDA award 2008-35203-19101 to JAA. (poster)

Progesterone responses to intravenous and intrauterine infusions of prostaglandin F2α in mares

The hypotheses were tested that prostaglandin F2alpha (PGF) travels from the uterus to the ovaries via a systemic route in mares, as opposed to a local route in ruminants, and that one pulse of PGF produces only partial luteolysis. Intravenous (i.v.) and intrauterine (i.u.) infusions of PGF were performed 8 days after ovulation at a constant rate for 2 h. Plasma concentrations of PGF were assessed by assay of 13,14-dihydro-15-keto-PGF2alpha (PGFM). Total doses administered were as follows: 0, 0.05, 0.1, 0.5 and 1.0 mg, i.v., PGF and 0 and 0.5 mg, i.u., PGF (n=4 mares per group). In addition, PGFM concentrations were determined for natural pulses from samples collected each hour during luteolysis (n=5). Progesterone was similarly reduced by 4 days after treatment in the 0.5 mg i.v., 0.5 mg i.u. and 0.0 mg i.u. groups. The area under the PGFM curve in the 0.1 mg i.v. group was similar to the area for natural PGFM pulses. Progesterone decreased to a similar concentration by 12 h in the 0.1, 0.5 and 1.0 mg i.v. groups, but thereafter was greater (P<0.05) in the 0.1 mg i.v. group. Progesterone concentrations reached <2 ng mL(-1) 6 days after treatment in the 0.05 and 0.1 mg i.v. groups and 2 days after treatment in the 0.5 and 1.0 mg i.v. groups. The results support the hypotheses of a systemic uteroluteal route for PGF transfer and that one pulse produces only partial luteolysis in mares.

Necessity of Sequential Pulses of Prostaglandin F2alpha for Complete Physiologic Luteolysis in Cattle1

The luteolytic effects of exogenous prostaglandin F2alpha (PGF) that did and did not simulate natural 13,14-dihydro-15-keto-PGF (PGFM) pulses were studied during mid-diestrus in 42 Holstein heifers. Plasma concentrations of PGF were assessed by assay of PGFM. In experiment 1, a single intrauterine injection of 4.0 mg of PGF into the uterine horn ipsilateral to the corpus luteum resulted in a precipitous progesterone decline, whereas sequential injections of 0.25 or 1.0 mg every 12 h resulted in a stepwise decrease (P < 0.05) following each injection. A progesterone increase occurred during the first 5 min before the luteolytic decrease but only for the 4.0-mg dose. From the results of experiment 2, a 2-h intrauterine infusion of a total of 0.5 mg of PGF was judged to best simulate a natural PGFM pulse. In experiment 3, simulation of sequential pulses at 12-h intervals resulted in a continuous precipitous decrease in progesterone to <1 ng/ml by the beginning of the fourth simulated pulse. In contrast, a single simulated pulse resulted in a 6-h progesterone decrease to a constant concentration for 3 days after treatment, followed by a return to control concentrations. The mean +/- SEM interval between the pretreatment and posttreatment ovulations was shorter (P < 0.05) in the group with sequential simulated pulses (14 +/- 1 day) than in the group with a single pulse (21 +/- 1 day). Results indicated that excessive PGF doses may stimulate nonphysiologic progesterone responses and supported the hypothesis that sequential PGF pulses are required to stimulate natural luteolysis in cattle.

Prostaglandin F2alpha concentrations in stallion semen and the effect of 24 hours of cold storage on exogenous prostaglandin F2alpha concentrations

Prostaglandin F2alpha concentrations in stallion semen and the effect of 24 hours of cold storage on exogenous prostaglandin F2alpha concentrations

Prostaglandin F2α produced by inducible cyclooxygenase may contribute to the resolution of inflammation

Cyclooxygenase-2 may play a role in resolution of carrageenan-induced pleurisy in rats by generating anti-inflammatory prostanoids. Here, we show exudate prostaglandin F2alpha concentrations rise during resolution of this model. These were reduced by the selective cyclooxygenase-2 inhibitor NS-398, which exacerbated inflammation. Concomitant treatment with NS-398 and the synthetic FP receptor agonist fluprostenol reversed this exacerbation. This suggests prostaglandin F2alpha produced by cyclooxygenase-2 contributes to resolution of this inflammatory reaction.

Mature atlantic salmon (Salmo salar L.) male parr are attracted to ovulated female urine but not to ovarian fluid.

The behavioral responses to urine and ovarian fluids from conspecific and heterospecific ovulated females were studied in mature Atlantic salmon (Salmo salar) male parr in a two-choice fluviarium. The males reacted differently to the stimulants. They spent more time in water scented by urine from salmon or brown trout (Salmo trutta L.) females compared to the time in water with ovarian fluids from salmon females. Furthermore, the males were attracted to salmon female urine (different from an indifferent reaction). Males exposed to urine of either species had higher plasma concentrations of testosterone (T) compared to unexposed controls. Measurement of the concentrations of prostaglandin F2alpha (PGF2alpha) and its major metabolite 15-ketodihydroprostaglandin F2alpha (15-ketodihydro-PGF2alpha) showed that the concentrations of the substances were higher in ovarian fluids of both species compared to those in urine. PGF2alpha showed a greater difference between ovarian fluid and urine than its major metabolite. The results suggest that urine of both species, in contrast to ovarian fluid, contain substances that attract mature Atlantic salmon male parr and that the active substances are neither PGF2alpha nor 15-keto-PGF2alpha.

Sustained activity of luteal cytosolic phospholipase A2 during luteolysis in pseudopregnant rats: its possible implication in tissue involution.

We investigated the expression and activity of cytosolic phospholipase A2 (cPLA2) in the corpus luteum during spontaneous and induced luteolysis in pseudopregnant rats. In both models, luteal PLA2 activity rose in association with functional regression and persisted during the following structural regression. Tissue concentration of prostaglandin F2alpha with a luteolytic potency showed a similar fluctuation. The enzyme activity was almost completely suppressed by a cPLA2-specific inhibitor. Expression of cPLA2, analyzed by immunohistochemistry, became enhanced during luteolysis with preferential localization to phagocytotic and fibrotic replacement sites. Taken together with our previous finding, the data indicate a persistent elevation in luteal cPLA2 expression and activity that may affect tissue involution in vivo.

Circadian variations of prostaglandins in the rabbit aqueous humor.

Forty-eight young adult New Zealand albino rabbits were entrained to a daily 12-hr light and 12-hr dark cycle. Under a constant dark environment, rabbits were sacrificed at 4-hr intervals, beginning at 2 hr before the accustomed lights-on period. Eight rabbits were used for each of the 6 time points within 24 hr. Aqueous humor and vitreous humor samples were collected. Samples from one eye of each rabbit were assayed for prostaglandins D2, E2, and F2alpha by enzyme immunoassay. Total protein concentrations in the samples were also determined. Concentrations of prostaglandins D2 and F2alpha in the aqueous humor were found to vary in a consistent pattern. The prostaglandin F2alpha concentration increased in the early subjective light period, remained high in this period, and decreased in the subjective dark period. The prostaglandin D2 concentration was elevated only in the early subjective light period. No significant change of aqueous humor prostaglandin E2 level was found. Total protein concentration in the aqueous humor varied in a similar pattern as the aqueous humor prostaglandin F2alpha, indicating a close association between the permeability of protein across the blood-aqueous barrier and the endogenous prostaglandin F2alpha level. In the vitreous humor, concentrations of all three prostaglandin subtypes remained unchanged, as did the total protein concentration. However, vitreous humor concentrations of prostaglandin D2 and F2alpha were significantly higher than their concentrations in the aqueous humor.

Improved Blood Substitute

The authors have previously documented that appropriate chemical and pharmacologic modification of the hemoglobin molecule are required to attenuate certain pathophysiologic reactions of the reticuloendothelium. The current study further investigates the molecular responses of human coronary artery endothelial cells to a high concentration (0.4 mmol) of 1) unmodified bovine hemoglobin; and 2) an improved blood substitute that comprises hemoglobin cross-linked intramolecularly with o-adenosine triphosphate and intermolecularly with o-adenosine, and conjugated with reduced glutathione. In this study, the scavenging effect of hemoglobins toward nitric oxide (NO) was evaluated by the measurement of nitrite (NO2-) and nitrate (NO3-) formation. The pro-oxidant effect of hemoglobin on endothelial cells was examined by the measurement of intracellular reduced glutathione, and by monitoring the formation of lipid hydroperoxides and 8-iso prostaglandin F2alpha, a novel potent vasoconstrictor, which is produced by a noncyclooxygenase mechanism involving free radical catalyzed peroxidation of arachidonic acid. The inflammatory reactions of endothelial cells were evaluated by the expression of the adhesion molecule, intracellular adhesion molecule-1, and the activation of nuclear transcription factor, nuclear factor kappaB. In additional, endothelial cell responses were investigated by analysis of intracellular ionized calcium concentrations. Results indicate that unmodified hemoglobin in a concentration of 0.4 mmol/L can aggravate endothelial cell oxidative and inflammatory responses. This hemoglobin produced a significant (p < 0.01) depletion of reduced glutathione, acceleration of lipid peroxidation, and a greater influx of Ca2+. The formation of 8-iso prostaglandin F2alpha increased compared with the control cells (p < 0.01). Unmodified hemoglobin was found to be a potent scavenger of NO, great activator of nuclear factor kappaB, and a stimulator of intracellular adhesion molecule-1 expression. Contrarily, the improved blood substitute did not appear to induce oxidative stress nor to increase the intracellular Ca2+. The concentration of 8-iso prostaglandin F2alpha was similar to that in the control cells, whereas the formation of NO2-/NO3- was much lower (p < 0.05) than in the unmodified hemoglobin group. The effect of an improved blood substitute can be linked with the anti-inflammatory and cytoprotective properties of adenosine, which is used as a cross-linker and surface modifier, and the type of the chemical modification procedure that lowers hemoglobin pro-oxidant potential.

Intrauterine irrigation with prostaglandin F2‐α for management of severe postpartum hemorrhage

Severe postpartum hemorrhage is a significant contributor to maternal morbidity and mortality. The use of prostaglandin F2-alpha to control severe postpartum hemorrhage may avert surgery for the control of bleeding. After ruling out the possibility of genital tract injuries, 18 patients with severe postpartum hemorrhage caused by uterine atony were enrolled in the study. None of the patients responded to treatment with oxytocin, methylergonovine, or uterine massage. A Foley catheter was introduced into the uterine cavity and the balloon was inflated with 5 ml sterile saline solution. The catheter was connected to an infusion line of 500 ml saline solution containing 20 mg prostaglandin F2-alpha. The solution was infused at a rate of 3-4 ml/minute for the first 10 min, and then reduced to 1 ml/minute for a period of 12 24 hours. In 17 patients (94.4%) bleeding ceased within several minutes of initiation of intrauterine prostaglandin F2-alpha infusion, the uterus was firmly contracted and uterine bleeding did not recur. In one patient with placenta increta bleeding continued and hysterectomy was performed. None of the patients had any side effects. Intrauterine irrigation with low concentrations of prostaglandin F2-alpha is a simple, rapid and effective treatment for severe postpartum hemorrhage and facilitates constant and continuous hemostasis. Moreover, the minute dosage used eludes potentially complicating side effects.

Hormone and prostaglandin F2 alpha regulation of messenger ribonucleic acid encoding steroidogenic acute regulatory protein in human corpora lutea.

Steroidogenic acute regulatory (StAR) protein mediates the rapid increase in steroid hormone biosynthesis in response to tropic hormones by facilitating transport of cholesterol into the inner mitochondrial membrane. Although our laboratory has recently reported on the hormonal regulation of StAR mRNA in the rat ovary, the same regulation in the human corpus luteum requires analysis. To this end, a human StAR complementary DNA (cDNA) probe of 858 bp was generated using reverse transcriptase-PCR and RNA from human corpora lutea. The StAR sequence was confirmed by dideoxy chain-termination sequence analysis. Northern blot analysis using the StAR cDNA probe on human corpora lutea mRNA showed that the probe hybridized to a major 1.6-kb transcript and a minor 4.4-kb transcript. Examination of corpora lutea of different luteal phases revealed that the basal expression of the 1.6-kb transcript was significantly more abundant in the early (days 15-19) luteal phase than in the middle (days 20-23) or late (days 24-28) phases. To examine the hormonal regulation of StAR mRNA, corpora lutea were treated in vitro with increasing concentrations of human chorionic gonadotropin (hCG) or prostaglandin F2 alpha (PGF2 alpha). Following hCG stimulation, both 1.6- and 4.4-kb StAR transcripts were increased. A statistically significant increase of 2.2- and 1.8-fold in the 1.6-kb transcript was seen with hCG concentrations of 50 and 100 mIU/mL, respectively. This increase was coupled with a significant elevation in media progesterone levels. In contrast, PGF2 alpha treatment significantly decreased both StAR messenger ribonucleic acid (mRNA) expression and media progesterone levels at concentrations of 500 and 5000 ng/mL. This investigation demonstrated that StAR mRNA is regulated by tropic hormones and prostaglandins in the human corpus luteum. The parallel change in StAR mRNA in conjunction with a change in progesterone levels further supports StAR's putative role in the regulation of steroidogenesis.

Steady-State Luteinizing Hormone Receptor Messenger Ribonucleic Acid Levels and Endothelial Cell Composition in Bovine Normal- and Short-Lived Corpora Lutea

The short-lived corpus luteum (CL) contributes to reproductive inefficiency during the postpartum period in beef cows. The cause for the early demise of the short-lived CL is not fully understood but is believed to involve a premature release of prostaglandin F2 alpha. The objectives of this study were to evaluate norgestomet-hCG-induced normal-lived CL and hCG-induced short-lived CL in postpartum cows with respect to serum progesterone (P4) and 13,14-dihydro-15-keto, prostaglandin F2 alpha (PGFM) concentrations and luteal LH receptor (LH-R) concentrations, LH-R mRNA levels, and vascularity. Although serum P4 profiles from the time of hCG administration (Day 0) until luteectomy (Day 6, 7, or 8) were similar between CL life span groups, PGFM concentrations were elevated (p < 0.05) on Day 8 in cows expected to have short-lived CL compared to normal-lived CL. The LH-R concentrations were similar between normal- and short-lived CL on all days measured. Irrespective of luteal life span and day of luteectomy, all CL possessed a 4.4-kb LH-R transcript. Actin-normalized LH-R mRNA levels were similar between normal- and short-lived CL on Days 6 and 7; however, Day 8 short-lived CL contained less (p < 0.05) LH-R mRNA than Day 8 normal-lived CL. Although the area of luteal tissue occupied by capillaries in normal- and short-lived CL was similar on Days 6 and 7, the area occupied by capillaries in short-lived CL was lower (p < 0.05) than that for normal-lived CL on Day 8. Collectively, these results indicate that there is a decrease in steady-state LH-R mRNA and a reduction in luteal vascularity in CL expected to be short-lived. These changes occur concomitantly with a rise in serum PGFM, but prior to a decline in serum P4.

Concentrations of prolactin and prostaglandins during and after cardiopulmonary resuscitation: Crit Care Med 1995; 23/8: 1347–1355

OBJECTIVES To assess differences in plasma prolactin and prostaglandin concentrations in resuscitated and nonresuscitated patients during cardiopulmonary resuscitation (CPR), and to compare changes of prostaglandin and prolactin concentrations with hemodynamic variables in the immediate postresuscitation phase. DESIGN Prospective, descriptive study. SETTING Emergency medical service at a university hospital. PATIENTS Twenty-nine patients ranging in age from 39 to 87 yrs with out-of-hospital cardiac arrest. INTERVENTIONS Venous blood samples were taken during CPR and at 5, 15, 30, and 60 mins after restoration of spontaneous circulation in order to measure plasma concentrations of prolactin, prostaglandin F2 alpha, 15-keto-13,14-dihydro-prostaglandin F2 alpha, 6-keto-prostaglandin F1 alpha, and thromboxane B2 by immunoassay. Heart rate and blood pressure were measured at 5, 15, 30, and 60 mins after restoration of spontaneous circulation. MEASUREMENTS AND MAIN RESULTS In 15 patients, restoration of spontaneous circulation was achieved; in the remaining 14 patients, successful resuscitation was not possible. During CPR, the mean plasma prolactin, prostaglandin F2 alpha, 15-keto-13,14-dihydro-prostaglandin F2 alpha, 6-keto-prostaglandin F1 alpha, and thromboxane B2 concentrations were 95.9 +/- 13.6 micrograms/L, 357 +/- 61 ng/L, 228 +/- 28 ng/L, 277 +/- 66 ng/L, and 375 +/- 78 ng/L, respectively, in resuscitated patients, and 23.9 +/- 5.6 micrograms/L (p = .0001), 192 +/- 22 ng/L (p = .005), 202 +/- 31 ng/L (p = .528), 221 +/- 40 ng/L (p = .713), and 344 +/- 77 ng/L (p = .780), respectively, in nonresuscitated patients. At 60 mins after restoration of spontaneous circulation, the mean plasma prolactin, prostaglandin F2 alpha, 15-keto-13,14-dihydro-prostaglandin F2 alpha, 6-keto-prostaglandin F1 alpha, and thromboxane B2 concentrations were 50.1 +/- 9.5 micrograms/L, 306 +/- 42 ng/L, 503 +/- 87 ng/L, 278 +/- 55 ng/L, and 355 +/- 30 ng/L, respectively. Mean values of systolic arterial blood pressure were 114 +/- 12 mm Hg at 30 mins and 123 +/- 18 mm Hg at 60 mins. No significant correlations were found between hemodynamic values and plasma concentrations of prolactin or prostaglandins. CONCLUSIONS Prolactin and prostaglandin concentrations were increased during cardiac arrest and CPR. Successful initial resuscitation was associated with increased prolactin and prostaglandin F2 alpha concentrations during CPR. Decreased concentrations in non-resuscitated patients may have been a result of exhaustion of the neuroendocrine and eicosanoid systems, or may be due to differences in bioavailability at the site of blood sampling based upon differences in hemodynamics.

Uterine circulatory dysfunction induced by whole-body vibration and its endocrine pathogenesis in the pregnant rat.

Effects of whole-body vibration on normal pregnancy were studied in the rat. Uterine blood flow and five endocrine functions corticosterone (CS), estradiol (E2), progesterone (P), prostaglandin E2 (PGE2) and prostaglandin F2 alpha (PGF2 alpha) concentration were measured in rats exposed to whole-body vibration with an acceleration of 10 m.s-2 at a frequency of 8 Hz. While no change in uterine blood flow was observed in control rats, uterine blood flow was significantly decreased 75 and 90 min after exposure to vibration. The uterine blood flow at 15 and 30 min was increased by pretreatment with intraperitoneal injections of angiotensin II (AII). In contrast, in AII pretreated rats exposed to the vibration, uterine blood flow was significantly reduced 90 min after exposure. The CS concentration was increased by vibration independently of the pretreatment with AII. Neither E2 nor PGF2 alpha concentration were changed by the vibration with or without AII administration. The P and PGE2 concentrations were both decreased by vibration in the absence of AII, while the decrease in PGE2 induced by the vibration was also found in AII-treated rats. The present results indicated that the pregnant rats subjected to whole-body vibration responded with changes in uterine and ovarian function. The observed decrease in uterine blood flow may have been the result of reduced PGE2 concentration resulting from an indirect effect of vibration.