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Biomedical subjects

M Ben-David

Publications and source records attributed to M Ben-David.

At least 37 records · Page 2Linked to original sources
PubMed1983

Transient hyperprolactinemia: a correctable cause of idiopathic female infertility.

Frequent measurements of prolactin throughout the menstrual cycle were obtained in 48 women with regular menses and longstanding idiopathic infertility. Forty-five of the 48 patients (94%) had a small but significant transitory preovulatory elevation in their serum prolactin levels (hPRL). These transitory elevations in hPRL to 27-70 ng/ml lasted only one to three days and coincided with the preovulatory estradiol peak. When this transient hyperprolactinemia was suppressed by treatment with an appropriate, titrated dose of bromergocriptine, 18 patients (40%) conceived within one to three months. Evidently, this transitory, relatively mild hyperprolactinemia was not sufficient to interfere with follicular maturation, ovulation, or corpus luteum function, but it may impair fertilization and/or implantation.

Adult↗
PubMed1983

Maternal and fetal serum prolactin levels in cases of premature rupture of membranes.

Serum prolactin levels were measured in maternal and fetal sera immediately post delivery in 20 cases of premature rupture of the membranes and in 20 controls. Fetal serum prolactin levels were 781 +/- 265 ng/ml in cases of PRM and 737 +/- 314 ng/ml in controls. Maternal serum prolactin levels were 504 +/- 264 ng/ml in cases of PRM and 731 +/- 361 ng/ml in controls. This difference is statistically significant (t = 1.81, p less than 0.05). A probable role of prolactin in maintaining fetal membrane integrity and the probable effect of the difference in maternal serum prolactin concentration in the two groups on the membranes' viscoelastic properties is discussed.

Elasticity↗
PubMed1982

Human ovarian receptors to human prolactin: implications in infertility.

In the human, hyperprolactinemia may interfere with fertility. To find out whether or not prolactin (PRL) can act directly on human ovarian tissues, in vitro studies involving specific binding of human PRL to various human ovarian elements were carried out. Human PRL was isolated from amniotic fluid, and its intact monomeric iodinated isohormone B was prepared. Labeled PRL was incubated with plasma membranes of either granulosa or whole follicular homogenates. Relatively high specific binding sites were obtained. Saturation studies and Scatchard analysis showed a single class of binding sites with high binding affinity (Kd = 1.8 x 10(8) M) and a concentration of 7.9 x 10(-15) moles/mg protein. These results clearly demonstrate the existence of specific receptors to isoprolactin B in ovarian elements with binding capacity and concentration at least equal to that found in other targets for PRL. It is reasonable to assume that hyperactivation of these receptors in states of hyperprolactinemia constitutes the cause for the disturbances in ovarian functions that lead to infertility.

Binding, Competitive↗
PubMed1982

Oxytocin-stressed and unstressed cardiotocograms for the prediction of fetal compromise.

The results of unstressed and oxytocin-stressed cardiotocograms recorded in 222 high-risk pregnancies within 48 h of delivery were compared with signs of fetal distress in labour and Apgar scores. Thirty-nine (18%) developed a late deceleration pattern in labour and 18 newborn (8%) had Apgar scores of less than 7 at 1 min. A direct comparison of the predictive value of unstressed and stressed cardiotocograms, using Fisher's exact test, showed a very significant difference in favour of the stressed cardiotocogram for the prediction of both fetal compromise and fetal well-being. The exclusion, or very selective use, of the oxytocin-stressed cardiotocogram and reliance on the unstressed cardiotocogram for the antepartum investigation of high-risk pregnancies sacrifices accuracy for convenience.

Adolescent↗
PubMed1981

Conservative management of suspected prolactin secreting pituitary adenoma during pregnancy.

Seventeen women with prolactin levels of 100 ng/ml and above suspected of harboring prolactin-secreting pituitary adenoma, from the basis of this study. Ten patients had radiological signs of an adenoma while in 7 the radiological criteria for such a diagnosis were not fulfilled. Ovulation and pregnancy were induced with bromocriptine in all 17 patients. They were carefully observed during pregnancy and following delivery. All gave birth to full-term babies after uneventful pregnancies, except for one patient who experienced intrauterine fetal death at 31 wk of gestation. It is our policy that women with suspected intrasellar prolactin-secreting pituitary adenoma be allowed to conceive and give birth without previous surgical intervention. The patient should be closely followed during pregnancy for clinical symptoms of enlargement of the tumor, including periodic visual field examinations. In cases of neurologic or ophthalmologic complications, surgery or bromocriptine administration without interruption of pregnancy is advocated, or if lung maturity is achieved, delivery should be induced.

Adenoma↗
PubMed1981

Prolactin concentration in prostates with benign hypertrophy.

Twenty-two hypertrophied prostates removed in surgery were checked for prolactin concentration by the radioimmunoassay method. The mean concentration in the prostatic tissue was found to be 38.2 +/- 1.9 ng./Gm. while the mean basal serum level was 11.9 +/- 1.3 ng./ml. It is concluded that serum prolactin levels do not reflect prostatic prolactin concentration. The possibility that interrelationship in action exists between androgens and prolactin affecting each other's concentration, both influencing prostatic metabolism is discussed.

Aged↗
PubMed1981

Effect of bromocriptine treatment on male infertility associated with hyperprolactinemia.

Hyperprolactinemia associated with male infertility or impotence was found in ten patients. Mean prolactin level was 83 +/- 49 ng/ml (range 46-26- ng/ml). The etiological bases of the hyperprolactinemia were a microadenoma in one patient, liver disease in two, and idiopathic in seven patients. Bromocriptine treatment, 2.5-7.5 mg daily for 8-16 weeks lowered prolactin to normal levels in all patients. Three oligoasthenospermic subjects showed a marked increase in sperm motility; their wives conceived within 5-8 weeks of treatment after longstanding infertility. Two of these women gave birth to normal babies and one aborted in the first trimester of pregnancy. The mechanism by which hyperprolactinemia interferes with sperm production and the effect of bromocriptine on this mechanism is discussed.

Adult↗
PubMed1981

Prolactin resistance to bromocryptine treatment: a case report.

High doses of bromocryptine (Parlodel, Sandoz) were successfully used for induction of ovulation followed by pregnancy in a hyperprolactinemic patient relatively resistant to bromocryptine treatment. After treatment with gradually increasing doses of bromocryptine, serum prolactin level (SPL) decreased slightly but became resistant and even elevated with increased doses. Under a high dose of bromocryptine (37.5 mg/d), the patient ovulated and conceived, despite the fact that SPL was not sufficiently reduced. The results may suggest that if a patient is somehow "resistant" to bromocryptine (as far as SPL suppression is concerned), a high dose may still be useful. The possibility that bromocryptine may have other effects on the process of ovulation than suppression of circulating prolactin is also to be considered.

Adult↗
PubMed1980

Bromocriptine treatment of hyperprolactinemic infertility with ovulatory disturbances.

We studied 77 women with hyperprolactinemic infertility and possible ovulatory disturbances. Galactorrhea was present in 27. Ovulation was normal in 15, 21 were anovulatory and 41 had luteal phase deficiency. All patients received bromocriptine for three months, resulting in normal serum prolactin levels. After that time, if no pregnancy occurred, clomiphene (with or without human chorionic gonadotropin) or human menopausal gonadotropin and human chorionic gonadotropin were added to the treatment. The overall pregnancy rate was 65%. The incidence of hyperprolactinemia in infertile patients is higher than expected, and patients with luteal phase deficiency can benefit from treatment with bromocriptine and ovulatory agents.

Adult↗
PubMed1980

Serum prolactin levels in men during retropubic prostatectomy.

Thirty-one patients who underwent retropubic prostatectomy under epidural anesthesia for benign hypertrophy of the prostate were checked for serum prolactin levels before and during operation. A significant increase in serum prolactin levels was noted during operation after the removal of the prostate, as compared with levels just prior to its removal. This difference suggests high concentration of prolactin in the prostatic tissue, part of which was released into the bloodstream during the traumatic squeezing of the prostate.

Humans↗
PubMed1980

Hyperprolactinemia: a possible cause of sexual impotence in male patients undergoing chronic hemodialysis.

Hyperprolactinemia is known to cause impotence in patients with normal renal function and elevated serum prolactin levels (SPLs) have also been reported in uremia. This study was undertaken to examine a possible role of elevated SPLs in the impotence of male patients undergoing chronic hemodialysis (CHD). SPLs in 16 male patients undergoing CHD were evaluated using a homologous double-antibody radioimmunoassay with prolactin isohormones isolated from human amniotic fluid. Patients were divided in 2 groups: 6 patients were sexually impotent and 10 sexually potent. Patients with emotional disturbances or marital conflicts known to cause impotence were excluded from the study. The SPLs of the impotent patients were found to be significantly elevated in comparison to the levels of the potent patients (136.7 +/- 28.2 vs. 37.3 +/- 2.7 ng/ml, p less than 0.001). Furthermore, in 2 patients who were successfully treated with bromocriptine to suppress hyperprolactinemia, recovery of sexual potency was noted. Thus, sexual impotence in male CHD patients seems to be associated with marked hyperprolactinemia. It is suggested that elevated SPLs may be an important cause of impotence among CHD patients.

Adult↗
PubMed1979

PRL and ACTH secretion following acute heat exposure, in intact and in hypothalamic deafferentated male rats.

Adult male rats, intact or bearing complete, anterior or posterior hypothalamic deafferentiations (CHD, AHD AND PHD, respectively) were acutely exposed to environmental temperature of 36 degrees C, and serum PRL and ACTH concentrations were determined by RIA. In intact animals, heat exposure resulted in elevated serum PRL and ACTH levels. None of the deafferentations affected basal serum PRL concentrations, whereas those of ACTH were elevated in both CHD and AHD, but not in PHD groups, as compared to intact controls. The PRL heat response was completely absent in CHD, attenuated in AHD, and delayed in PHD animals, and the ACTH heat response was absent in all three groups. These results demonstrate (1) that acute exposure to elevated environmental temperature stimulates secretion of PRL and of ACTH; (2) that this stimulation is carried out by diverse neural pathways; and, (3) that hypothalamic modulation of the secretion of PRL and ACTH is effected by independent mechanisms.

Adrenocorticotropic Hormone↗
PubMed1979

Twenty-four-hour rhythm of prolactin depressive patients.

Twenty-four-hour rhythms of serum prolactin (PRL) levels were studied in seven depressive patients. Blood was collected through an indwelling catheter and the PRL level was determined by homologous double antibody radioimmunoassay. Findings showed a different pattern of secretion of prolactin among depressives as compared to the normal 24-hour rhythm of the hormone. A statistically significant elevation of PRL levels during the evening, several hours before sleep, was found. Morning PRL levels were slightly higher and the average increase of PRL level from one determination to the consecutive one was higher among the depressives. It is assumed that there may be a connection between the diurnal rhythmicity of mood, characteristic of vital depression, and the different 24-hour rhythmicity of PRL level.

Adjustment Disorders↗
PubMed1979

Male hyperprolactinemia:effects on fertility.

Male hyperprolactinemia was detected in 4% (7 of 171) of infertile men. In seven patients with excessive serum prolactin concentrations, the clinical manifestations were infertility, hypogonadism, impotence, and galactorrhea and the etiologic factors were pituitary adenoma, hypothalamic dysfunction, drug use, and idiopathic. The testes and prostate were small or normal and the semen analysis revealed low semen volume, normal or low sperm count, and normal or impaired sperm motility. The testicular biopsy showed normally preserved seminiferous tubules with normal or decreased spermatogenesis and damaged or fibrotic seminiferous tubules among normal ones. Patients with hyperprolactinemia were investigated by sellar polytomography, visual field examinations, and hormone assays. Treatment with bromocriptine (Parlodel) gave satisfactory results in all patients. The use of bromocriptine with human menopausal gonadotropin and human chorionic gonadotropin was beneficial in treating hypogonadotropic hypogonadism with hyperprolactinemia.

Adult↗
PubMed1979

Evidence of lack of passage of human prolactin through human placental membranes.

Human prolactin (hPRL) derived from either amniotic fluid (AF) or pituitary was tested for its passage capability through amniotic and chorionic membranes placed in an in vitro perfusion chamber. The passage of both 'cold' and labelled prolactin were investigated using intact monomeric iodinated hPRL isolated from amniotic fluid which also served as a tracer in a homologous double antibody radioimmunoassay used for prolactin determinations. Throughout 4 h incubation period at 37 degrees C, there was no passage of 'cold' hPRL from either of the sources across either direction. Also, in contrast to free iodine ions, there was no passage of intact labelled prolactin in either direction. Decomposition of labelled prolactin occurred only in the chorionic side, and only decomposed labelled prolactin molecules passed into the amniotic side. These became detectable 1 h after commencement of incubation. These results may explain the long half-life and the high concentration of hPRL in amniotic fluid, and also suggest that the source of AF hPRL is not maternal.

Amnion↗