• 한국가금학회지
• /
• 제23권3호
• /
• pp.113-119
• /
• 1996

A series of experiments were conducted to investigate the role of protein kinase C (PKC) as a second messenger in vasoactive intestinal peptide (VIP) mediated prolactin secretion. Primary pituitary cells (106 cells/treatment) were separated from laying hens and incubated in M-199 with 5% chicken serum and 5% fetal calf serum. The VIP(0.1 $\pi$M) treatment enhanced prolactin Secretion into media upto 9-fold during 48-h incubation. The phorbol 12-myristate 13-acetate (PMA), a PKG agonist, increased prolactin secretion upto 2-fold at 0.1 nM PMA (P<0.01), and the prolactin secretion was not significantly higher than this concentration. Staurosporine (ST; 1.0$\pi$M) a PKC antagonist, decreased by 70% of 0.1 $\pi$M VIP-stimulated prolactin secretion and by 48% of 10 ${\mu}$M PMA-stimulated prolactin secretion (P<0.01). However, pituitary cell prolactin content did not differ in any treatment (P>0.05). In conclusion, these results indicate that the PKC second messenger system is involved in VIP-stimulated prolactin release in chicken primary pituitary cell culture.

• 생약학회지
• /
• 제9권1호
• /
• pp.33-39
• /
• 1978

The present study is involved with the prolactin secretion from anterior pituitary gland by ginseng saponin since it was handled down by tradition that ginseng might influence the milk secretion when it was given to nursing mother. To investigate the effect of saponin on the prolactin production or release from the anterior pituitary gland, cell culture study and whole animal studies were carried out. For the cell culture study, enzymatically dispersed anterior pituitary cells of rat anterior pituitary gland in HEPES buffers containing trypsin were used. Ginseng saponin was added to the culture media and the amount of prolactin produced in the cell culture media was determined by radloimmunoassay(RIA) technique. Dose-dependent increases of prolactin with ginseng saponin were observed, whereas, no change was observed without ginseng treatment. For the whole animal study, normal and castrated rats which previously cannulated into the heart via the right juglar vein were used. The prolactin concentration in plasma were determined by using the technique of RIA. In normal rats, prolactin concentration in plasma were elevated dramatically after 1 hour of ginseng saponin administration, whereas, instantaneous increases were observed in castrated rats. For prolactin assay by RIA, NIAMDD Rat Prolactin Kit and NIAMDD Rat Prolactin RP-1 were used as standard. The results indicate that ginseng saponins increase the release of prolactin from the anterior pituitary gland and production of prolactin from the cell in rats.

• Applied Microscopy
• /
• 제23권1호
• /
• pp.25-34
• /
• 1993

Prolactin has been reported to be present in the tear film of humans and prolactin-like immunoreactivity has been detected by immunofluorescence in acinar cells of the lacrimal glands of humans and rats. The present study was aimed at clarifying the intracellular distribution of the prolactin-like immunoreactivity, using the electron microscope immunogold technique. The lacrimal gland acinar cells have two types of secretory granules: 1) Secretory granules containing flocculent materials irregularly shaped and are often coalesced. 2) Secretory granules are fairly round and contain homogenous materials of a moderate electron density. The density of the granular content varies even within a single cell. We found prolactin-like reactivity in secretory granules, some smaller cytosolic vesicles, Golgi cisternae and nuclei in acinar cells from intact glands of rat. Our present results are consistent with the conclusion that prolactin is present in lacrimal cells. The presence of prolactin reactivity in the nucleus suggests that prolactin may be a regulatory factor modulating gene expression.

• 핵의학기술
• /
• 제27권2호
• /
• pp.133-136
• /
• 2023

Purpose: Prolactin in the blood is separated into three types, and over 90% of prolactin presents as a double monomer (23 KDa). Rarely, it can exist in the size of big prolactin (150 KDa), which is called macroprolactin and is known as an autoantibody complex. When macroprolactin accounts for more than 60% of prolactin in the blood, it is called macroprolactinemia. The presence of such macroprolactin was first reported in a patient with hyperprolactinemia but without typical symptoms. Macroprolactinemia is emerging as an important cause of idiopathic hyperprolactinemia. The polyethylene glycol (PEG) precipitation method using the property of precipitating large-molecular-weight proteins is simple and recently has been widely used as a screening test. The results are in good agreement with the results of gel chromatography. The purpose of this study was to confirm the measurement method and reference value verification of monomeric prolactin in blood prolactin using the PEG precipitation method. Materials and Methods: For 40 examinees who visited the Gangnam Center of Seoul National University Hospital in 2021, the prolactin level was verified using radioimmunoassay (RIA). For macroprolactinemia PEG precipitation method, 25% PEG (molecular weight 6000kDa) solution and serum were mixed in equal amounts in a test tube, then left at room temperature for 20 minutes and centrifuged at 4℃ for 30 minutes (1500g). The prolactin level was measured in the supernatant. Results : After confirming that more than 90% of the 40 tested samples within the reference range <25 ng/mL, the same value as the reference value for prolactin was applied. Since the concentration of monomeric prolactin in serum from which macroprolactin has been removed from blood is diluted 1:1 with PEG, our laboratory is currently reporting the result by multiplying the result by a dilution factor of 2. Conclusion: Radioimmunoassay using PEG precipitation method using the property of precipitating large molecular weight proteins is simple and effective for quantitative measurement of monomeric prolactin in blood prolactin.

• Animal cells and systems
• /
• 제3권2호
• /
• pp.103-113
• /
• 1999

Many in-depth reviews related to regulations of prolactin secretion are available. We will, therefore, focus on controversial aspects using personal opinion in this review. The neuroendocrine control of prolactin secretion from the anterior pituitary gland involves multiple factors including prolactin-release inhibiting factor (PIF) and prolactin releasing factor (PRF). The PIF exerts a tonic inhibitory control in the physiological conditions. The PIF should be able to effectively inhibit prolactin release or a lifetime, but the inhibitory action of dopamine cannot be sustained for a long period of time. Perifusion of a high concentration of dopamine (l ,000 nM) could not sustain inhibitory action on prolactin release but when a small amount of ascorbic acid (0.1 mM) is added in a low concentration of dopamine (3 nM) solution, prolactin release was inhibited for a long period. Ascorbate is essential for dopamine action to inhibit prolactin release. We have, therefore, concluded that the PIF is dopamine plus ascorbate. The major transduction system for dopamine to inhibit prolactin release is the adenylyl cyclase system. Dopamine decreases cyclic AMP concentration by inhibiting adenylyl cyclase, and cyclic AMP stimulates prolactin release. However, the inhibitory mechanism of dopamine on prolactin release is much more complex than simple inhibition of CAMP production. The dopamine not only inhibits cyclic AMP synthesis but also inhibits prolactin release by acting on a link(s) after the CAMP event in a chain reaction for inhibiting prolactin release. Low concentrations of dopamine stimulate prolactin release. Lactotropes are made of several different subtypes of cells and several different dopamine receptors are found in pituitary. The inhibitory and stimulatory actions induced by dopamine can be generated by different subtype of receptors. The GH$_4$ZR$_7$ cells express only the short isoform (D$_{2s}$) of the dopamine receptor, as a result of transfecting the D$_{2s}$ receptors into GH$_4$C$_1$ cells which do not express any dopamine receptors. When dopamine stimulates or inhibits prolactin release in GH$_4$ZR$_7$ cells, it is clear that the dopamine should act on dopamine D$_{2s}$ receptors since there is no other dopamine receptor in the GH$_4$ZR$_7$. Dopamine is able to stimulate prolactin release in a relatively low concentration while it inhibits in a high concentration in GH$_4$ZR$_7$. These observations indicate that the dopamine D$_2$ receptor can activate stimulatory and/or inhibitory transduction system depending upon dopamine concentrations.

• Archives of Pharmacal Research
• /
• 제3권2호
• /
• pp.85-86
• /
• 1980

Dopaminergic influences on prolactin release from lactotrophs have been studied using the rat anterior pituitary cell culture. The prolactin inhibiting activity of hypothalamic extracts was examined in relation to dopamine. Dopamine inhibited prolactin secretion from the rat anterior pituitary cell culture in a dose dependent fashion. The median effective dose was $2{\times}10^{-7}$ / M and the maximal inhibition (70-90 % of the control value) was shown by 10$^{-5}$ / M dopamine. Further increase in dopamine concentration did not result in any further inhibition of prolactin secretion.nhibition of prolactin secretion.

• 정신신체의학
• /
• 제4권2호
• /
• pp.207-214
• /
• 1996

본 연구의 목적은 시험스트레스 및 vitamin B 복합제가 혈장 ACTH, cortisol 및 prolactin치에 미치는 영향을 알아보고자 하는 데 있다. 본 연구는 의과대학 2학년 학생들 중 시험 4주전, 시험 2주전 및 시험기간 세차례를 모두 완료한 21명을 대상으로 하였다. 상기 혈장 hormone치는 방사성 면역분석법에 의해 측정되었다. 그리고 스트레스지각 및 정신병리는 global assessment of recent stress(GARS)척도와 SCL-90R척도를 사용하여 평가되었다. 혈장 ACTH치는 시험 4주전에 비해 시험 2주전과 시험기간 중에 각각 유의하게 더 높게 나타났다. 그러나 세기간 중 혈장 cortisol과 prolactin치는 각각 유의한 차이를 보이지 않았다. 한편 vitamin B투여 유무 간에는 혈장 ACTH, cortisol 및 prolactin치는 각각 유의한 차이를 보이지 않았다. 또한 시험 2주전에 경제적 문제와 관련된 스트레스지각 점수는 혈장 ACTH 및 prolactin치와 유의한 양상관성을 보였다. 시험 2주전에 적대감척도 점수는 혈장 ACTH치와 유의한 양상관성을, 편집증척도 점수는 혈장 ACTH치와 양상관성의 경향을, 시험기간 중 불안척도 점수는 혈장 cortisol치와 양상관성의 경향을 보였다. 시간경과는 물론 vitamin투여 유무에 따른 혈장 ACTH, cortisol 및 prolactin치의 변화량에 있어서도 유의한 차이를 보이지 않았다. 결론적으로 시험스트레스에 대해서 cortisol이나 prolactin보다는 ACTH가 더 예민한 반응을 나타내고, 주관적 스트레스지각이나 시험전 적대감 및 편집증, 그리고 시험기간 중 불안과 같은 정신병리가 상기 hormone과 관련될 가능성이 높다. 그러나 vitamin B복합제는 스트레스에 의한 상기 hormone의 변화에 영향을 미치지 않음을 시사한다.

• 생물정신의학
• /
• 제7권1호
• /
• pp.74-79
• /
• 2000

본 연구의 목적은 치료 용량의 비정형적 항정신병 약물(risperidone, olanzapine)의 성 호르몬(prolactin과 testosterone)에 대한 효과를 알아보기 위해 총 91명의 정신분열병 환자들의 혈청에서 prolactin과 testosterone의 농도를 측정하였다(haloperidol 28명, 4~20mg/day ; risperidone 31명, 2~6mg/day ; olanzapine 32명, 5~20mg/day). 그 결과 남자 환자에서 olanzapine 복용자의 혈청 prolactin 농도가 risperidone이나 haloperidol 복용자의 혈청 농도보다 낮았으나 risperidone 복용자와 haloperidol 복용자의 혈청 prolactin 농도는 상호 유의한 차이가 없었다. 여자 환자에서는 olanzapine 복용자의 혈청 prolactin 농도가 risperidone이나 haloperidol 복용자의 혈청 농도보다 낮았으며 risperidone 복용자의 prolactin 농도는 haloperidol 복용자보다 낮았다. 또한 남자, 여자 환자 모두에서 haloperidol, risperidone, olanzapine을 각각 복용한 사람들의 혈청 testosterone 농도는 유의한 차이가 없었다. 위의 결과로 저자는 치료 용량에서 risperidone은 혈청 prolactin 농도를 haloperidol 만큼이나 증가시키지만 olanzapine의 경우 혈청 prolactin 농도에는 영향을 끼치지 않으며 비정형적 항정신병 약물은 testosteron의 농도에는 영향을 끼치지 않는다는 것을 알 수 있었다.

• 생물정신의학
• /
• 제10권2호
• /
• pp.177-185
• /
• 2003

Object:We investigated the relationship between prolactin response to antipsychotics and clinical courses of psychotic symptoms and DAT gene polymorphisms. Method:Twenty-four acute psychotic inpatients completed the 12-week trial of risperidone. Serum prolactin, BPRS, ESRS and hyperprolactinemia-related symptoms were measured at baseline, 2, 4, 8 and 12 weeks after medication. The DAT gene polymorphisms were analyzed. Results:The serum prolactin was significantly increased over time. According to the prolactin level at 2-week, the subjects were divided into the severe group(serum prolactin>60ng/mL, N=15) and the mild group (serum prolactin<60ng/mL, N=9). The prolactin levels of the mild group didn't increase beyond 60ng/mL throughout 12 weeks. Severe group had slower decrement of BPRS scores than those of mild group. Six females in severe group complained of irregular menstruations, but no female in mild group. Most patients had 10 allele of DAT gene. Conclusion:This study suggests that the magnitude of prolactin elevation at the 2-week of risperidone medication is correlated with severity of hyperprolactinemia throughout treatments. Our results did not show the relationship between prolactin responses and DAT gene polymorphisms.

• 대한약리학회지
• /
• 제28권1호
• /
• pp.19-25
• /
• 1992

Nonbenzodiazepine계 항불안제인 buspirone을 이용하여 건강한 8명의 남자를 대상으로 prolactin과 cortisol분비를 측정하였다. Buspirone는 $Dopamine_2$ 수용체 antagonist 성질 뿐 아니라 $5-HT_{1A}$ partial agonist 효과가 있는 것으로 보고되고 있다. Buspirone 30mg 경구투여시 혈청 prolactin 농도는 유의한 증가를 보였으나 혈청 cortisol 농도의 변화는 차이가 없었다. beta adrenoreceptor antagonist이면서 $5-HT_{1A}$ 수용체 antagonist로 알려진 pindolol (30mg)을 경구 투여한 결과 기초 혈청 prolactin이나 cortisol 농도는 유의한 차이가 없었다. Pinodlol을 전처치한 경우 buspirone-induced prolaction 분비의 유의한 억제효과는 없었다. 이상의 성적은 buspirone-induced prolactin 분비증가는 아마도 $5-HT_{1A}$ 수용체 활성과 관련되지 않음을 시사하는 것으로 사료된다.