PubMed Health⌕ Search

Biomedical subjects

S Pitoulis

Publications and source records attributed to S Pitoulis.

12 recordsLinked to original sources
PubMed1988

Chronic antidepressant treatment increases the apomorphine-induced elevation of plasma corticosterone in rats.

Plasma corticosterone concentrations in response to subcutaneous administration of apomorphine (25 and 200 micrograms kg-1) have been assessed in rats treated acutely (2 days) or repeatedly (15 days) with saline, clomipramine, electroshock and clomipramine + electroshock. Chronic, but not acute, antidepressant treatment decreased the corticosterone level which remained unchanged in control and in rats acutely treated with apomorphine. Chronic antidepressant treatment significantly increased the corticosterone response to apomorphine. Neuroendocrine evidence is provided for an increased responsiveness of dopamine receptors which are thought to mediate the apomorphine effect on corticosterone secretion following chronic antidepressant treatment.

Animals↗
PubMed1986

Therapeutic efficacy of a somatostatin analogue (SMS 201-995) in active acromegaly.

Twelve patients with active acromegaly, six of whom had not responded to previous combined surgery, radiotherapy, and bromocriptine administration, were treated with an octapeptide long-acting somatostatin analogue, SMS 201-995, given subcutaneously for up to 1 year. Growth hormone (GH) levels decreased by 50% to 90% after a single 25-micrograms SMS 201-995 injection in all patients, including two who were resistant to bromocriptine therapy. After GH values reached a nadir, they returned to preinjection values over a 12-hour period and no rebound was seen. Assessment of the GH-lowering effect of the drug at weekly intervals for the first 6 weeks and monthly thereafter disclosed no tachyphylaxis. Gradual increase of the dose from 50 to 150 micrograms daily led to a significant increase in clinical improvement. Shrinkage of the size of the pituitary tumor was documented in three of nine evaluated cases. Abdominal cramps of a transient nature not associated with diarrhea were noted in two patients but there were no other side effects. Hematological and biochemical blood and urine tests, including serum thyroxine and cortisol levels, did not reveal any abnormality during chronic treatment. This study demonstrates the safety and efficacy of SMS 201-995 in the short-term treatment of acromegaly.

Acromegaly↗
PubMed1981

Results of three-times-per-week long-term administration of a luteinizing hormone-releasing hormone (LHRH) analog, D-Ser-(TBU)6-LHRH-(EA)10 in primary amenorrhea.

The effectiveness of a luteinizing hormone (LH)-releasing hormone (LHRH) analog, D-Ser-(TBU)6-LHRH-(EA)10 (Hoe 766), applied intranasally in a 3 days-per-week regimen, was assessed in four patients with hypogonadotropic or normogonadotropic primary amenorrhea by measuring LH, follicle-stimulating hormone (FSH), and estradiol (E2) levels before and 4 hours after its application and by observing the clinical effects of these hormones on the genital tract. The LH response increased progressively over the first 21 days (nine applications) in three of the four patients; it was subsequently reduced but never abolished throughout the study, which was terminated with the 25th application on the 59th day. Basal values of E2 increased until the 12th to 14th day (fifth or sixth application) and then showed a definite decline despite the continuing increase in LH response. FSH release attained a maximum by the second to fourth application and its magnitude of response remained remarkably stable thereafter. The clinical response did not correspond to the serum levels of E2. It is postulated that the development of LH unresponsiveness is due to desensitization of the receptors by the analog. The poor response of the genital tissues to the normal levels of E2 and the subsequent decrease in E2 levels, which occurred despite increasing LH responsiveness, are attributed to an inhibitory action of the analog on E2 biosynthesis in the ovary and on E2 receptors in the genital organs.

Adult↗
PubMed1981

Induction of ovulation and pregnancy in a pituitary dwarf.

Females with pituitary dwarfism of the multiple pituitary hormone deficiency form have ovarian failure due to hypogonadotropism which would be expected to respond favorably to human gonadotropin treatment. This is a description of a pituitary dwarf in whom pregnancy was achieved with gonadotropin therapy; its progress was followed regularly by hormone assays.

Adult↗
PubMed1981

Prolactin and placental hormone levels during pregnancy in prolactinomas.

Prolactin (PRL) and the placental hormones, estradiol (E2), estriol (E3), progesterone (PG), chorionic gonadotropin (HCG), and placental lactogen (HPL) were serially measured throughout pregnancy and early postpartum in three patients with prolactinomas in whom pregnancy was achieved by one of the three modalities of treatment: bromocriptine administration (patient I), irradiation of the pituitary (patient II), and human gonadotropin administration after excision of the adenoma (patient III). It was found that PRL in patient I reached the high pretreatment levels in the 2nd month of pregnancy and increased to further abnormal concentrations in the last 2 months, but fell at the onset of labor 1 week after an episode of severe headache. The PRL changes in this patient were attributed successively to tumor expansion and apoplexy. In patient II PRL decreased after irradiation, but was not normalized. During pregnancy it remained moderately increased presenting minor fluctuations. The third patient with postoperative GH and TSH pituitary insufficiency had low pretreatment PRL levels which remained practically unchanged throughout pregnancy. The two last patients gave birth to identical twins. The placental hormones were found normal in all three patients but E2 and PG were relatively increased during the last weeks of pregnancy in the twin pregnancies. Amniotic fluid and umbilical cord PRL and E2 concentrations were normal. The patients presented agalactia and suckling did not induce a PRL increase. We conclude that a) serial PRL measurements during pregnancy reflect the changes occurring in the prolactinomas and are essential in monitoring the patients bearing these tumors; b) maternal hyperprolactinemia or failure of PRL to increase during pregnancy do not influence either the secretion of placental hormones or PRL concentration in amniotic fluid and the newborn; and c) hyperprolactinemia during pregnancy is of maternal pituitary origin.

Adenoma↗
PubMed1980

Pituitary-gonadal function in three relatives presenting with Kallmann's syndrome.

The assumption that abnormalities exist in both the pituitary and gonads was tested in 3 familial cases of Kallmann's syndrome, 2 brothers, aged 16 and 17 years, and their cousin, aged 26 years. Serial serum and urinary LH and FSH titers were measured after subcutaneous administration of 100 micrograms LRH and in the 2 brothers after a second test using 400 micrograms LRH. Serum testosterone and estradiol were estimated before and 60 and 90 min after LRH and also before and on the 3rd and 4th day after daily administration of 5,000 IU of hCG for 3 days. Prolactin was also measured in blood samples of all LRH tests and found normal in 2 cases and increased in 1. Tomograms of the pituitary fossa were normal in this patient. With all procedures used, a distinct stimulatory effect on the pituitary and the testes failed to appear in the patients of the present study.

Adolescent↗
PubMed1979

Prolactin levels during labor.

To test the hypothesis that prolactin (PRL) plays a role in the hormonal events of labor, serum PRL levels in 15 normal secundigravidas were measured on 2 occasions 10-15 days before delivery, at the onset of labor, at cervical dilatation of 5 and 10 cm, at the time of delivery, and on the first, second, and fifth days postpartum. The mean level of PRL was 163 ng/ml +/- 26 ng/ml at the onset of cervical dilatation; it typically decreased with the progress of labor, reaching a value of 140 ng/ml +/- 21 ng/ml at the time of delivery. The differences during the various stages of labor, however, were not found to be statistically significant. Postpartum values were significantly lower (P less than 0.01) on the fifth day after parturition. It is therefore unlikely that PRL is involved in or influenced by the hormonal interplay that occurs during labor.

Delivery, Obstetric↗