Effect Of Bromocriptine Administration Research Articles

Effect of bromocriptine administration on the heart rate, prolactin, growth hormone, and adrenocorticotropin responses to a two-minute exercise bout in geldings

Effect of bromocriptine administration on the heart rate, prolactin, growth hormone, and adrenocorticotropin responses to a two-minute exercise bout in geldings

Effect of Bromocriptine administration on semen physical characteristics and related hormones in Iraqi male goats

The present study was carried out at the farm of College of Veterinary Medicine –University of Baghdad, during the period from 30 / 9 / 2007 to 1 / 5 / 2008. The aim of thisstudy was to investigate the influences of Bromocriptine treatment on the semencharacteristics and related hormones ( Prolactin, LH, Testosterone and Cortisol ). To get thesegoals, this study designed depending on 14 mature bucks divided into two groups. Bucks ofthe group ( B ) received orally 5 mg of bromocriptine ( Parlodel )® per animal per day forfive consecutive days and gain a second treatment with interval of 14 days in the sameschedule of administration. Control group ( C ) injected with distil water only. Data collectedand statistically analyzed and the results were tabulated:Treatment of group B bucks with Bromocriptine resulting in significant (P<0.05 ) increasesof semen volume. Also the viability of sperms represented by mass and progressive motilitieswere increased significantly than those of control bucks’ semen. Percentage of life spermswas higher significantly than that of control bucks semen. Whereas, abnormalities of spermwas significantly lower than control. Concentration of sperm was elevated significantlycompared with control bucks’ sperm concentration. Bromocriptine treatment causedsignificant decline in prolactin hormone concentration. This lowering was accompanied withsignificant increase in testosterone hormone. While, cortisol hormone and LH not affected bybromocriptine treatment.From these results, it may be concluded that; bromocriptine treatment improves bothlibido and semen characteristics and have a special role in shortening sexual arresting periodof bucks

Effect of Bromocriptine Administration during Mid-pregnancy on the Ovary Function in the Pig

Plasma concentrations of prolactin, luteinizing hormone (LH), progesterone, estradiol-17 beta and androgens testosterone with dihydrotestosterone were determined in pregnant gilts (n = 6) administered bromocriptine (BR) from 37-42 days of pregnancy. Blood samples were daily taken at 2h-intervals from day 34 to 45 of pregnancy. BR treatment reduced (p less than 0.001) prolactin secretion from 14.8 +/- 0.9 ng/ml to 8.6 +/- 1.1 and 5.5 +/- 0.7 during the initial 1-3 and 4-6 days of treatment, respectively. Following cessation of BR treatment prolactin returned to the pre-treatment concentrations (14.5 +/- 1.0). BR did not alter LH during the first 3 days of treatment but decreased LH on days 4-6 (1.5 +/- 0.1 vs 2.1 +/- 0.2, p less than 0.05). Bromocriptine evoked a 20% increase (p less than 0.05) in estradiol-17 beta during days 1-3 following onset of treatment, however it suppressed androgen concentrations from 10.7 +/- 1.2 to 5.6 +/- 0.4 pg/ml in the same period. Suppression of prolactin from day 37-42 with a concurrent decrease of LH from day 40-42 of gestation did not affect maintenance of pregnancy and surprisingly was associated with a temporary elevation of progesterone. We conclude that prolactin has no luteotrophic properties during midpregnancy in gilts.

Effect of Bromocriptine Administration on Maintenance of Late Pregnancy in the Pig

Plasma concentrations of prolactin, luteinizing hormone (LH) and progesterone were determined in pregnant gilts (n = 6) administered bromocriptine from 67-72 days of pregnancy. Blood samples were taken daily at 2 h intervals from 60 to 80 days of pregnancy. Bromocriptine treatment reduced prolactin from 9.7 +/- 1.4 before to 1.9 +/- 0.6 ng/ml during the treatment (p less than or equal to 0.05) and then returned to the pre-treatment concentrations (10.5 +/- 2.0) following cessation of bromocriptine. Bromocriptine increased LH from 1.4 +/- 0.2 before treatment to 2.9 +/- 0.5 ng/ml (p less than or equal to 0.01) during administration and maintained elevated (3.0 +/- 0.7) in the post-treatment period (p less than or equal to 0.05). Administration of bromocriptine did not alter progesterone concentration in plasma (7.5 +/- 1.2; 7.2 +/- 1.6 and 6.6 +/- 1.6 ng/ml in pretreatment, treatment and post-treatment periods, respectively). This study shows that decrease of prolactin level by bromocriptine treatment does not cause depletion of progesterone secretion in late pregnant pigs.

Effects of bromocriptine administration during the follicular phase of the oestrous cycle on prolactin and gonadotrophin secretion and follicular dynamics in merino monovular ewes

Two experiments using Spanish Merino ewes were conducted to investigate whether the secretion of prolactin during the follicular phase of the sheep oestrous cycle was involved in the patterns of growth and regression of follicle populations. In both experiments, oestrus was synchronized with two cloprostenol injections which were administered 10 days apart. Concurrent with the second injection (time 0), ewes (n = 6 per group) received one of the following treatments every 12 h from time 0 to 72 h: group 1: vehicle injection (control); group 2: 0.6 mg bromocriptine (0.03 mg per kg per day); and group 3: 1.2 mg bromocriptine (0.06 mg per kg per day). In Expt 1, blood samples were collected every 3 h from 0 to 72 h, and also every 20 min from 38 to 54 h to measure prolactin, LH and FSH concentrations. In Expt 2, transrectal ultrasonography was carried out every 12 h from time 0 until oestrus, and blood samples were collected every 4 h to measure prolactin, LH and FSH concentrations. Ovulation rates were determined by laparoscopy on day 4 after oestrus. Bromocriptine markedly decreased prolactin secretion, but did not affect FSH concentrations, the mean time of the LH preovulatory surge or LH concentrations in the preovulatory surge. Both doses of bromocriptine caused a similar decrease in LH pulse frequency before the preovulatory surge. The highest bromocriptine dose led to a reduction (P < 0.01) in the number of 2-3 mm follicles detected in the ovaries at each time point. However, bromocriptine did not modify the total number or the number of newly detected 4-5 mm follicles at each time point, the number of follicles > 5 mm or the ovulation rate. In conclusion, the effects of bromocriptine on gonadotrophin and prolactin secretion and on the follicular dynamics during the follicular phase of the sheep oestrous cycle indicate that prolactin may influence the viability of gonadotrophin-responsive follicles shortly after luteolysis.

Effects of bromocriptine administration during the follicular phase of the oestrous cycle on prolactin and gonadotrophin secretion and follicular dynamics in merino monovular ewes

Two experiments using Spanish Merino ewes were conducted to investigate whether the secretion of prolactin during the follicular phase of the sheep oestrous cycle was involved in the patterns of growth and regression of follicle populations. In both experiments, oestrus was synchronized with two cloprostenol injections which were administered 10 days apart. Concurrent with the second injection (time 0), ewes (n = 6 per group) received one of the following treatments every 12 h from time 0 to 72 h: group 1: vehicle injection (control); group 2: 0.6 mg bromocriptine (0.03 mg per kg per day); and group 3: 1.2 mg bromocriptine (0.06 mg per kg per day). In Expt 1, blood samples were collected every 3 h from 0 to 72 h, and also every 20 min from 38 to 54 h to measure prolactin, LH and FSH concentrations. In Expt 2, transrectal ultrasonography was carried out every 12 h from time 0 until oestrus, and blood samples were collected every 4 h to measure prolactin, LH and FSH concentrations. Ovulation rates were determined by laparoscopy on day 4 after oestrus. Bromocriptine markedly decreased prolactin secretion, but did not affect FSH concentrations, the mean time of the LH preovulatory surge or LH concentrations in the preovulatory surge. Both doses of bromocriptine caused a similar decrease in LH pulse frequency before the preovulatory surge. The highest bromocriptine dose led to a reduction (P &lt; 0.01) in the number of 2-3 mm follicles detected in the ovaries at each time point. However, bromocriptine did not modify the total number or the number of newly detected 4-5 mm follicles at each time point, the number of follicles &gt; 5 mm or the ovulation rate. In conclusion, the effects of bromocriptine on gonadotrophin and prolactin secretion and on the follicular dynamics during the follicular phase of the sheep oestrous cycle indicate that prolactin may influence the viability of gonadotrophin-responsive follicles shortly after luteolysis.

A study with diagnostic standard of occult hyperprolactinemia (OHP) and the effect of bromocriptine administration

It is well known that the transient excessive increase of serum prolactin level is harmful for the mechanism of ovulation or the steroidogenesis of the ovaries. The pathogenesis of latent or occult hyperprolactinemia (OHP) has been investigated recently. The present study was conducted to determine the diagnostic standard of OHP, and to elucidate the efficacy of bromocriptine administration for the treatment of OHP and other ovulatory disturbances. 110 cases of hypothalamic anovulations were selected from 385 cases of infertile patients by the LH-RH and TRH loading tests. Bromocriptine (5mg/day) was administered to all of the subjects for more than three months, and the efficacy of the bromocriptine administration was investigated. Follicular development was observed by transvaginal ultrasonography (mature follicular diameters > or = 20mm), and also luteal function was estimated by the duration of the luteal phase in the BBT charts (high phase > or = 12 days), the mid-luteal serum estradiol (> or = 200pg/ml) and progesterone (> or = 10ng/ml) levels. The subjects were divided into two groups: group A, bromocriptine effective patients (63 cases) and group B, bromocriptine non effective patients (47 cases). The results of the LH-RH and TRH loading tests were compared between these two groups. Serum prolactin levels at 30 min. after TRH loading (PRL30) in group B (61.5 +/- 28.3 vs. 38.0 +/- 19.3ng/ml, p < 0.01). At the cut-off points of 50, 60 and 70ng/ml over in the values of the PRL, the efficacies of the bromocriptine administration were 77.4, 78.9 and 88.5%, respectively. From these facts, it was thought suitable that the diagnostic standard of OHP was PRL30 > or = 70ng/ml, and values of PRL30 from 50 to 70ng/ml were borderline cases of OHP. The efficacy of the bromocriptine administration in the cases without OHP (n = 57) was also investigated. Serum LH levels at 30 min. after LH-RH loading (LH30) were compared between the cases of the bromocriptine effective (n = 22) and non effective (n = 35). As a result, the LH30 of the former was significantly higher than that of the latter (96.5 +/- 64.2 vs. 45.1 +/- 31.5mIU/ml, p < 0.005). In conclusion, the diagnostic standard of OHP was determined as PRL30 > or = 70ng/ml (borderline: 50 > 70ng/ml), and bromocriptine administration was effective not only in cases of OHP, but also in cases of hyperreactivities of LH (so-called endocrinological PCOD).

Comprehensive Approach to Clinical Background and Effect of Bromocriptine Administration in the Patients of Endocrinological PCO

Present study was performed to elucidate the clinical features and the treatment of so-called endocrinological polycystic ovarian disease (PCO). 36 cases out of 189 infertile patients who had various ovulatory disturbances were subjected during past four years. They were selected by the definitions as follows; 1) serum LH levels greater than or equal to 30 mIU/ml and serum FSH levels less than or equal to 15 mIU/ml, 2) hyper-response of LH secretion by LH-RH (100 micrograms) loading test; maximum values greater than or equal to 250 mIU/ml. Serum androstenedione (ASD), dehydroepiandrosterone-sulfate (DHA-S), estrone (E1), estradiol (E2), progesterone (P, in the mid-luteal phase) and testosterone (T) levels were examined by RIA method for the purpose of the evaluation of the endocrinological background of the PCO in Japanese women. The same examinations were also done in 8 volunteer women who had normal ovulatory menstrual cycles for the control study. In 6 cases of the PCO patients who showed biphasic BBT charts, the endometrial biopsy was done in the mid-luteal phase at the same time of the blood sampling. And the correlation between various serum hormone levels and the endometrial morphology in the PCO patients was also discussed. Then bromocriptine (5 mg/day) was administered in these patients for more than 30 days and the effect of the treatment was investigated. Serum ASD levels in the PCO patients were significantly higher than those in the control (2.52 +/- 1.30 vs. 1.43 +/- 1.21 ng/ml, M +/- S.D., p less than 0.05), while serum E2 and P levels in the patients were significantly lower than those in the control (E2: 118.6 +/- 39.5 vs. 192.5 +/- 53.9 pg/ml, p less than 0.005. P: 7.26 +/- 5.08 vs. 124.4 +/- 4.6 ng/ml, p less than 0.005, respectively). There were no significant differences in serum levels of the other hormones. By the administration of bromocriptine, serum ASD levels decreased (1.62 +/- 1.34 ng/ml, p less than 0.05), and E2 (177.9 +/- 48.6 pg/ml, p less than 0.025) and P (11.8 +/- 4.3 ng/ml, p less than 0.005) levels increased significantly into the levels of control. Serum LH levels of the patients were also suppressed by the treatment of bromocriptine (42.5 +/- 13.7 vs. 27.4 +/- 12.0 mIU/ml, p less than 0.005), however there was no change in serum FSH levels.(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of bromocriptine administration on gastric acid and gastrin secretion in man.

The effects of acute oral administration of the dopaminergic drug, bromocriptin (5 mg), on basal and submaximal (1 and 3 microgram per kg bw given sc) and maximal (6 mug per kg bw) pentagastrin-stimulated gastric acid secretion and on basal and meal-induced gastrin release have been evaluated in healthy volunteers. Although basal and maximal pentagastrin-stimulated acid output did not change, the response to submaximal pentagastrin doses was significantly increased. Basal and stimulated serum gastrin concentrations were not modified, nor was fasting serum gastrin during chronic bromocriptine treatment (10 mg per day for 90 days) in acromegalic patients. As dopamine infusion is known to reduce basal and pentagastrin-induced gastric acid secretion, the presently reported effect of bromocriptine is not dependent on dopamine receptor stimulation. It is suggested that it might be due to alpha-adrenergic and/or serotoninergic antagonism, both actions being properties of bromocriptine. Alternatively, since bromocriptine, at variance with iv infused dopamine, crosses the blood-brain barrier, the effect of this drug on gastric function might depend on interference by centrally mediated actions on those directly exerted at the gastric level.

Treatment of Amenorrhoea, Galactorrhoea and Hypogonadism with Bromocriptine*

The effect of bromocriptine administration was studied in 34 patients, whose presenting symptoms included amenorrhoea, galactorrhoea, infertility, dyspareunia, delayed puberty, and impotence. Two patients were found to have raised plasma prolactin values during investigation for acromegaly. With the exception of three individuals all patients had hyperprolactinaemia. Pituitary fossa enlargement or asymmetry was reported in 16 patients and one patient had primary hypothyroidism. Virtually all patients complained of side effects when first starting bromocriptine but only two patients were unable to tolerate prolonged therapy with doses which ranged from 5--40 mg daily. A single oral dose of 2.5 mg resulted in a greater than 50% reduction in plasma prolactin within five hours in 22 of 26 patients. Over the course of one month, five patients with significant pituitary fossa enlargement appeared to show less rapid suppression of plasma prolactin than five patients without fossa enlargement. At two months this trend was still evident but eventually all patients showed acceptable control of plasma prolactin, with the exception of one patient who required pituitary surgery. Galactorrhoea ceased in 13 of 15 patients, menstrual periods resumed in ten of 13 patients, two patients becoming pregnant first. Potency returned and puberty proceeded in two hypogonadal males. Six of the nine patients requesting treatment for infertility became pregnant. It is concluded that bromocriptine provides effective treatment for galactorrhoea, amenorrhoea or gonadal disorders when there is associated hyperprolactinaemia.