THE STIMULATION OF PROLACTIN SECRETION BY SULPIRIDE IN "ADOLESCENT GYNAECOMASTIA"

1977 ◽  
Vol 85 (4) ◽  
pp. 692-697
Author(s):  
R. D'Agata ◽  
S. Andó ◽  
S. Gulizia ◽  
L. Condorelli ◽  
C. Paci ◽  
...  
Keyword(s):  
Baseline Level ◽  
Prolactin Secretion ◽  
Serum Prolactin ◽  
Maximum Increase ◽  
The Mean ◽  
Pituitary Prolactin ◽  
Stimulation Of

ABSTRACT In order to evaluate the function of the hypothalamic-pituitary-prolactin axis in "adolescent gynaecomastia" (AG), sulpiride was administered to 7 normal boys and 7 boys with AG. The maximum increase in serum prolactin (PRL) above the mean baseline level (Δmax) was used as index of response. The sulpiride induced a greater PRL release in boys with gynaecomastia than in the controls. Our data indicate that boys with gynaecomastia may have a greater pituitary prolactin pool. The results also illustrate the usefulness of specific neurotrophic agents such as sulpiride as important tools for evaluating the function of the hypothalamic-pituitary-PRL axis.

Stimulation of prolactin secretion by oestradiol in the rat is associated with increased hypothalamic release of thyrotrophin-releasing hormone

1984 ◽  
Vol 103 (2) ◽  
pp. 257-261 ◽  
Author(s):  
S. Franks ◽  
H. D. Mason ◽  
K. I. J. Shennan ◽  
M. C. Sheppard
Keyword(s):  
Incubation Medium ◽  
Prolactin Secretion ◽  
Serum Prolactin ◽  
Thyrotrophin Releasing Hormone ◽  
Releasing Hormone ◽  
Threefold Increase ◽  
Rat Pituitary ◽  
Pituitary Glands ◽  
Pituitary Prolactin ◽  
Stimulation Of

ABSTRACT We have studied the effect of oestradiol (OE2) on secretion of prolactin and TSH by rat pituitary glands and correlated this with changes in hypothalamic content and release of thyrotrophin-releasing hormone (TRH). Ovariectomized Wistar rats received s.c. silicone elastomer implants of OE2 at a dose known to give pro-oestrous OE2 levels. After 1 week rats were decapitated, blood was collected for assay of prolactin and TSH, blocks of hypothalamus were dissected out and pituitary glands were removed and bisected. Medium bathing hemipituitary glands was collected for measurement of prolactin and TSH after a 30-min incubation. Immunoreactive TRH was measured in medium removed from hypothalami and in extracts of homogenized hypothalami. Serum prolactin was higher in OE2-treated than in control animals (59·3 ± 19·5 (s.e.m.) vs 9·4 ± 1·5 μg/l; P<0·05) and this was associated with a threefold increase in pituitary prolactin in the medium. By contrast, TSH concentrations in serum and pituitary incubation medium were not significantly different in the two groups. There was no difference between the groups in hypothalamic content of TRH but TRH release in the incubation medium was increased by OE2 (30·2 ± 6·5 vs 10·0 ± 1·3 pg/mg protein per 30 min; P<0·01). In summary, physiological levels of OE2 stimulated prolactin secretion without change in TSH and this was associated with a threefold increase in hypothalamic release of TRH. These findings suggest that the stimulating effect of OE2 on prolactin secretion may, in part, be mediated by hypothalamic TRH. J. Endocr. (1984) 103, 257–261

Potentiation of sulpiride-induced prolactin secretion by sodium deprivation in man

1980 ◽  
Vol 94 (1) ◽  
pp. 25-29 ◽  
Author(s):  
Masatomo Mori ◽  
Isao Kobayashi ◽  
Kihachi Ohshima ◽  
Sakae Maruta ◽  
Yohnosuke Shimomura ◽  
...  
Keyword(s):  
Control Diet ◽  
Normal Subjects ◽  
Sodium Content ◽  
Prolactin Secretion ◽  
Serum Prolactin ◽  
Aldosterone Secretion ◽  
Low Sodium Diet ◽  
Specific Radioimmunoassay ◽  
Prolactin Response ◽  
Pituitary Prolactin

Abstract. Previous studies suggest that prolactin is not an important osmoregulatory hormone in man, while aldosterone is well known to be important in osmoregulation. The present investigation was undertaken to ascertain whether serum osmotic changes affect pituitary prolactin secretion following sulpiride administration. Five normal subjects were placed on a constant isocaloric diet with different sodium content. Serum prolactin and aldosterone level were measured by specific radioimmunoassay. The basal serum level of prolactin was unaffected by changes in sodium content of the diet, in contrast to the basal level of aldosterone. On the other hand, the maximum levels of serum prolactin in response to sulpiride (50 mg, im) were significantly higher on a low sodium diet (3 g of salt/day) than on a control diet (12– 15 g of salt/day). When the content of diet changed from low salt to high salt (25 g of salt/day), sulpiride-induced prolactin response decreased, though it was not significantly lower than that on a control diet. However, sulpiride administration could not stimulate aldosterone secretion under any of the various sodium contents of the diet. The present study provides evidence that lowering of serum osmolarity stimulates serum prolactin response to sulpiride administration in man and this response is not modulated by aldosterone secretion.

ONSET OF OESTROGEN-INDUCED PROLACTIN SECRETION AND DNA SYNTHESIS BY THE RAT PITUITARY GLAND

1977 ◽  
Vol 72 (1) ◽  
pp. 35-39 ◽  
Author(s):  
JOAN JACOBI ◽  
H. M. LLOYD ◽  
J. D. MEARES
Keyword(s):  
Dna Synthesis ◽  
Pituitary Gland ◽  
Prolactin Secretion ◽  
Male Rat ◽  
Serum Prolactin ◽  
Rat Pituitary ◽  
The Times ◽  
Pituitary Prolactin

SUMMARY The times of onset of oestrogen-induced prolactin secretion and DNA synthesis were studied in the pituitary gland of the male rat. At intervals from 3 to 96 h after injection of 10 mg diethylstilboestrol dipropionate, serum and pituitary prolactin concentrations were measured by radioimmunoassay and pituitary DNA synthesis by incorporation of [3H]thymidine in vitro. Serum prolactin was raised significantly from 6 h onwards and DNA synthesis was increased from 30 h onwards. Pituitary prolactin concentration began to increase at 30 h. Significant correlations were obtained between serum prolactin and DNA synthesis from 24 to 72 h but not during the period of prolactin secretion from 6 to 24 h.

Influence of lactotroph cell density on prolactin secretion in rats

1992 ◽  
Vol 134 (2) ◽  
pp. 241-NP ◽  
Author(s):  
H. A. Pasolli ◽  
A. I. Torres ◽  
A. Aoki
Keyword(s):  
Volume Density ◽  
Experimental Models ◽  
Prolactin Secretion ◽  
Morphological Data ◽  
Ovariectomized Rats ◽  
Molecular Forms ◽  
Serum Prolactin ◽  
Pituitary Glands ◽  
Prolactin Content ◽  
Stimulation Of

ABSTRACT The relationships between the stimulation of prolactin secretion and proliferation of lactotrophs was studied from a multidisciplinary standpoint in three experimental models. Administration of both oestrogen and sulpiride resulted in a significant increase in prolactin secretion and in the lactotroph population. A single injection of 10 μg oestradiol benzoate (OB) induced a twofold increase in the proliferation of lactotrophs (morphometrically as volume density), which increased further (2·5-fold) after three OB injections. Parallel changes were observed in the net counts made on lactotrophs sectioned through the nucleus to avoid possible distortions in volume density caused by hypertrophic cytoplasms. Comparable results were obtained with the mitotic index in the same groups of rats exposed to treatment with colchicine. The effect of sulpiride on proliferation of lactotrophs was also significant (1·7-fold) but less pronounced than in rats treated with oestrogens. The treatments with oestrogen and sulpiride did not stimulate lactotrophic activity in a similar way, as judged by the levels of serum prolactin and the storage patterns of small and big prolactin in pituitary glands. Serum prolactin (mean ± s.e.m.) in control ovariectomized rats was 4·0±0·9 μg/l and one and three injections of OB raised these levels to 14·4±5·0 and 28·8±4·6 μg/l respectively. The highest levels of serum prolactin were seen in sulpiride-treated rats (467·2±28·7 μg/l). Striking differences occurred in the pituitary contents of big prolactin, the control values increasing from 5·3±0·5 to 10·2±1·3 μg/mg after one OB injection and to 14· 7 ±0·7 μg/mg after three OB injections. In contrast, the concentration of big prolactin in sulpiride-treated rats was very low (1·85 ± 0·2 μg/mg), 2·8-times smaller than the controls. Other changes were also found in the small prolactin content in pituitary tissue with higher values in all the experimental models. These differences could only be detected after differential extraction of big and small molecular forms of prolactin. In ovariectomized rats, treatment with several doses of oestrogen enhanced the proliferation observed in the lactotroph population and increased the number of mitoses. In turn, morphological data could be closely related to the higher levels of prolactin in serum and pituitary glands. A sustained stimulation of lactotrophic secretion was always followed by proliferation of lactotrophs, the number of which fluctuated in parallel with the degree of stimulation. Journal of Endocrinology (1992) 134, 241–246

DNA SYNTHESIS AND DEPLETION OF PROLACTIN IN THE PITUITARY GLAND OF THE MALE RAT

1978 ◽  
Vol 77 (1) ◽  
pp. 129-136 ◽  
Author(s):  
H. M. LLOYD ◽  
J. M. JACOBI ◽  
J. D. MEARES
Keyword(s):  
Growth Hormone ◽  
Dna Synthesis ◽  
Hormone Secretion ◽  
Growth Hormone Secretion ◽  
Prolactin Secretion ◽  
Male Rats ◽  
Male Rat ◽  
Serum Prolactin ◽  
Inhibitory Effects ◽  
Pituitary Prolactin

Haloperidol, bromocriptine and diethylstilboestrol dipropionate were given in various régimes to male rats to determine their effects on pituitary DNA synthesis, prolactin secretion and growth hormone secretion. Haloperidol increased serum prolactin but did not stimulate pituitary DNA synthesis or reduce pituitary prolactin concentrations. Haloperidol potentiated the effects of oestrogen on serum prolactin and on pituitary DNA synthesis; pituitary prolactin concentrations were greatly reduced, and growth hormone secretion was slightly inhibited. The inhibitory effects of bromocriptine in oestrogen-stimulated rats were demonstrated by smaller pituitary weights and decreased DNA synthesis; serum prolactin levels were lowered and pituitary prolactin concentrations were increased. Haloperidol, given to rats treated with oestrogen and bromocriptine, reversed the inhibitory effects of bromocriptine on DNA synthesis and serum prolactin; pituitary prolactin concentrations fell to well below normal. The results suggest that the haloperidol potentiation of oestrogeninduced pituitary DNA synthesis may depend upon stimulation of prolactin secretion together with reduction of intracellular prolactin levels.

SERUM CONCENTRATIONS OF PROLACTIN, LUTEINIZING HORMONE, GROWTH HORMONE, CORTICOSTERONE, PROGESTERONE, TESTOSTERONE AND OESTRADIOL IN RELATION TO BROODINESS IN DOMESTIC TURKEYS (MELEAGRIS GALLOPAVO)

1981 ◽  
Vol 89 (2) ◽  
pp. 187-195 ◽  
Author(s):  
S. HARVEY ◽  
E. BEDRAK ◽  
A. CHADWICK
Keyword(s):  
Laying Hens ◽  
Hormone Secretion ◽  
Meleagris Gallopavo ◽  
Prolactin Secretion ◽  
Egg Laying ◽  
Serum Prolactin ◽  
Ovulatory Cycle ◽  
Light Darkness ◽  
Nocturnal Increase ◽  
The Mean

Variations in concentrations of LH, GH, prolactin, corticosterone, oestradiol, testosterone and progesterone in serum were followed over a 24 h period (14 h light: 10 h darkness) in laying and broody turkeys and in turkeys suspected of becoming broody (pre-broody hens). In laying hens marked variations in LH and gonadal steroid levels were observed in relation to the ovulatory cycle of the bird. These patterns of hormone secretion were not seen in either group of broody birds. Levels of GH in serum were very variable and showed no correlation with the egg-laying or light: darkness cycle and the concentrations did not differ between the respective physiological states. A nocturnal increase in the concentration of corticosterone in serum was observed in all three groups of turkeys and the concentration was occasionally higher in the pre-broody and broody birds than in the laying hens. The serum prolactin concentration in each group was also very variable and showed no obvious relationship with the ovulatory or photoperiodic cycle. The mean circulating prolactin concentration throughout the 24 h period did not differ significantly between the groups. These results suggest that broodiness in the domestic turkey is not initiated or maintained by enhanced prolactin secretion.

INHIBITION OF PITUITARY PROLACTIN SECRETION BY HUMAN PLACENTAL LACTOGEN IN RATS

1976 ◽  
Vol 71 (1) ◽  
pp. 115-120 ◽  
Author(s):  
HIROSHI NAGASAWA ◽  
REIKO YANAI ◽  
KOREHITO YAMANOUCHI
Keyword(s):  
Prolactin Secretion ◽  
Female Rats ◽  
Placental Lactogen ◽  
Ovariectomized Rats ◽  
Serum Prolactin ◽  
Corpora Lutea ◽  
Human Placental Lactogen ◽  
Vaginal Smears ◽  
Pituitary Prolactin

SUMMARY Intact female rats given twice daily injections of 1 mg human placental lactogen (HPL) showed continued dioestrous vaginal smears and their ovarian corpora lutea were found to be hypertrophied and functional. The serum prolactin level was significantly lower in these rats than in the controls at dioestrus as well as at pro-oestrus. Twice-daily injections of 0·5 or 2 mg HPL to ovariectomized rats decreased serum and pituitary levels of prolactin and increased hypothalamic activity of prolactin inhibiting hormone, although the effect was less at the lower dose. Human placental lactogen had no direct effect on pituitary prolactin secretion in vitro. These findings have demonstrated that HPL, like prolactin itself, inhibits prolactin secretion by acting indirectly on the pituitary through the hypothalamus.

CHROMATOGRAPHY OF THE 17-KETOGENIC STEROIDS IN THE DIAGNOSIS AND CONTROL OF CONGENITAL ADRENAL HYPERPLASIA

1960 ◽  
Vol XXXIII (II) ◽  
pp. 230-250 ◽  
Author(s):  
Eileen E. Hill
Keyword(s):  
Congenital Adrenal Hyperplasia ◽  
List Type ◽  
Adrenal Hyperplasia ◽  
Normal Children ◽  
Paediatric Practice ◽  
The Mean ◽  
Cortisone Therapy ◽  
And Control ◽  
Clinical Problems ◽  
Stimulation Of

ABSTRACT A method for the fractionation of the urinary 17-ketogenic steroids with no oxygen grouping at C11 and those oxygenated at C11, is applied to the clinical problems of congenital adrenal hyperplasia. In normal children the mean ratio of the non-oxygenated to oxygenated steroids is 0.24. In childrern with congenital adrenal hyperplasia the ratio is 2.3. The reason for this difference in ratio is discussed. The changes in ratio found under stimulation of the adrenal gland with exogenous or endogenous corticotrophin and the suppression with cortisone therapy are studied. This test can be applied to isolated samples of urine, a major advantage in paediatric practice, and can be carried out in routine laboratories. It is found to be reliable in the diagnosis and sensitive in the control of congenital adrenal hyperplasia.

Deep brain stimulation of the posterior limb of the internal capsule in the treatment of central poststroke neuropathic pain of the lower limb: case series with long-term follow-up and literature review

2020 ◽  
Vol 133 (3) ◽  
pp. 830-838 ◽  
Author(s):  
Andrea Franzini ◽  
Giuseppe Messina ◽  
Vincenzo Levi ◽  
Antonio D’Ammando ◽  
Roberto Cordella ◽  
...  
Keyword(s):  
Neuropathic Pain ◽  
Lower Limb ◽  
Internal Capsule ◽  
Posterior Limb ◽  
Vas Score ◽  
The Mean ◽  
Deep Brain ◽  
Stimulation Of

OBJECTIVECentral poststroke neuropathic pain is a debilitating syndrome that is often resistant to medical therapies. Surgical measures include motor cortex stimulation and deep brain stimulation (DBS), which have been used to relieve pain. The aim of this study was to retrospectively assess the safety and long-term efficacy of DBS of the posterior limb of the internal capsule for relieving central poststroke neuropathic pain and associated spasticity affecting the lower limb.METHODSClinical and surgical data were retrospectively collected and analyzed in all patients who had undergone DBS of the posterior limb of the internal capsule to address central poststroke neuropathic pain refractory to conservative measures. In addition, long-term pain intensity and level of satisfaction gained from stimulation were assessed. Pain was evaluated using the visual analog scale (VAS). Information on gait improvement was obtained from medical records, neurological examination, and interview.RESULTSFour patients have undergone the procedure since 2001. No mortality or morbidity related to the surgery was recorded. In three patients, stimulation of the posterior limb of the internal capsule resulted in long-term pain relief; in a fourth patient, the procedure failed to produce any long-lasting positive effect. Two patients obtained a reduction in spasticity and improved motor capability. Before surgery, the mean VAS score was 9 (range 8–10). In the immediate postoperative period and within 1 week after the DBS system had been turned on, the mean VAS score was significantly lower at a mean of 3 (range 0–6). After a mean follow-up of 5.88 years, the mean VAS score was still reduced at 5.5 (range 3–8). The mean percentage of long-term pain reduction was 38.13%.CONCLUSIONSThis series suggests that stimulation of the posterior limb of the internal capsule is safe and effective in treating patients with chronic neuropathic pain affecting the lower limb. The procedure may be a more targeted treatment method than motor cortex stimulation or other neuromodulation techniques in the subset of patients whose pain and spasticity are referred to the lower limbs.

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