Cigarette smoking decreases the prolactin response to serotonergic stimulation in subgroups of alcoholics and controls

BACKGROUND: The prolactin response to serotonergic stimulation has been used as an index of central nervous system serotonin function. We evaluated the prolactin response to d,l-fenfluramine to determine whether subtypes of alcoholics differed in prolactin responsivity compared with nonalcoholics and whether cigarette smoking affected prolactin response. METHODS: One hundred ten healthy, abstinent men across four groups (controls [23% smokers]; alcoholics [72% smokers]; alcoholics with antisocial personality disorder [94% smokers]; nonalcoholic antisocials [88% smokers]) received d,l-fenfluramine (100 mg orally) in a randomized, double-blind, placebo-controlled study. Plasma prolactin levels were obtained at baseline and at half-hour intervals for 5 hr after fenfluramine/placebo administration. Plasma fenfluramine and norfenfluramine levels were obtained hourly. RESULTS: Smokers had a blunted prolactin response to fenfluramine compared with nonsmokers without any alcoholism or antisocial personality effects. Using a cutoff point of delta peak prolactin < 10 ng/ml, more smokers (41/76, 54%) had a dampened response to fenfluramine than did nonsmokers (7/34, 21%) [chi2(1) = 10.6, p < 0.003]. The percentage of low responders was greatest among smokers regardless of whether they were healthy controls, alcoholics, or antisocial. Multiple regression revealed that three variables--(1) number of pack-years of smoking, (2) actual dosage of fenfluramine received, and (3) plasma norfenfluramine level obtained--explained 43% of the variance (R2 = 0.43) in delta prolactin area under the curve. Variables that included alcoholism diagnostic status, antisocial personality diagnostic status, and impulsive aggressive personality, depressive, and suicidal traits failed to explain any additional unique variance. CONCLUSIONS: Cigarette smoking blunted the prolactin response to a pharmacological challenge with d,l-fenfluramine. Pharmacodynamic and pharmacokinetic factors related to smoking both appear to influence fenfluramine-induced prolactin secretion. Phenotypes of alcoholics did not differ in their prolactin response to this serotonergic probe.     

催乳素对人B淋巴细胞IgG基因表达影响的实验研究

目的:研究人催乳素(PRL)对B淋巴母细胞系IM-9细胞IgG基因表达的影响。方法:应用人PRL(10ng/ml)刺激IM-9细胞,培养48h后用试剂盒提取细胞总RNA,反转录为cDNA,RT-PCR扩增IgGcDNA,琼脂糖凝胶电泳观察扩增情况。结果:该cDNA片段的大小为98bp,LPS、PRL与LPS-PRL组cDNA条带在第24循环时出现,LPS-Br与LPS-PRL-Br组cDNA条带在第28循环时出现,并随循环数的增加亮度逐渐增强,LPS-PRL组该cDNA条带亮度最强。结论:PRL能够上调B淋巴细胞中IgG基因的表达,但该功能能够被Br拮抗。     

电针少泽穴治疗产后缺乳46例临床观察

目的评价电针少泽穴治疗产后缺乳的临床疗效,探讨电针对不同证型、不同年龄患者的影响。方法选取产后缺乳患者92例,随机分为治疗组46例,对照组46例。治疗组电针双侧少泽穴,对照组电针双侧商阳穴。均5次为1个疗程,共治疗2个疗程,并随访1个月。结果治疗组总有效率100%,对照组为69.6%,两组比较差异有显著性意义(P<0.01)。对于不同证型、不同年龄的患者,治疗组在提高泌乳量、维持催乳素水平方面均明显优于对照组,两组比较差异有显著性意义(P<0.01)。结论电针少泽穴治疗产后缺乳临床疗效显著。     

产前焦虑对产妇激素水平与母乳喂养的影响

目的分析产前焦虑对产妇催产素、催乳素水平与母乳喂养情况的影响。方法采用前瞻性研究方法，选择102例无焦虑产妇、焦虑组31例产妇为研究对象，用放射免疫法测定两组产妇产后血清催产素、催乳素含量，调查两纽产妇产后泌乳始动时间以及住院、产后1个月母乳量。结果分娩后焦虑组平均血清激素水平为，催产素（23．14±6．08）ng／ml，催乳素（110．15±14．46）ng／ml；无焦虑组平均血清激素水平为，催产素（64．39．4-29．81）ng／ml，催乳素（178．22．±20．38）ng／ml，两组激素水平差异均有统计学意义（P〈0．05）。焦虑组产后住院时乳量情况为：多48．4％，中35．5％，少6．5％，无9．7％；无焦虑组为：多73．5％，中21．6％，少2．9％，无2．0％，两组泌乳量差别有统计学意义（P〈0．05）。结论焦虑产妇产后血清催产素、催乳素水平低，泌乳始动时间晚，产后1年内母乳喂养失败的风险高。     

Effect of venipuncture stress on plasma prolactin levels

Venipuncture for blood collection is postulated to be a stress factor that can increase circulating prolactin (PRL) and therefore produce false results. Seven normal non-pregnant women and 44 gravidae were submitted to venipuncture with a butterfly needle connected to a syringe for vein maintenance. Blood was collected immediately (zero time) and 15 and 30 min after venipuncture. After the last collection, a vein in the contralateral arm was punctured in the non-pregnant women only and a new blood sample was collected. PRL, measured by immunoassay, varied from 7 to 13.2 ng/ml in the non-pregnant women and from 7 to 300 ng/ml in the gravidae. No significant difference in PRL values was detected at any of the collection times. It is concluded that the stress or pain caused by venipuncture is not sufficient to alter plasma PRL levels in normal (non-pregnant) or hyperprolactinemic (gravidae) women.     

Blunted prolactin response to metoclopramide in insulin-dependent diabetic patients with secondary amenorrhoea

Summary In order to investigate the dopaminergic activity in diabetic women with secondary amenorrhoea we studied the response of prolactin to a dopamine receptor antagonist metoclopramide (MTC-10 mg i.v.) in three groups of women: 5 insulin-dependent diabetic women with secondary amenorrhoea, 5 insulin-dependent diabetics with normal menstrual cycles and 6 non-diabetic women with regular cycles.Patients with diabetes and secondary amenorrhoea had significantly lower basal LH levels (P<0.001) and FSH levels (P<0.005) than normally cycling diabetic women. Basal and metoclopramide stimulated prolactin levels were lower in diabetic women with secondary amenorrhoea compared to normally cycling diabetics and control subjects.Evaluation of C-peptide levels in peripheral blood revealed that all amenorrhoic diabetics had no endogenous beta cell function while diabetic women with normal cycles (except 1 patient) had preserved residual pancreatic beta cell secretion.     

Effect of repeated administration of prolactin releasing peptide on feeding behavior in rats

Prolactin releasing peptide (PrRP) has been reported to reduce food intake in rats. We tested the effect of i.c.v. administration of PrRP-31 on food intake in both food deprived and free-feeding rats. We did not find any effect of PrRP-31 on food intake after single injections of up to an 8-nmol dose, but observed a marked decrease in food intake and body weight in rats that received a repeated twice daily administration of 8 nmol of PrRP-31. This effect was associated with an adverse behavioral pattern, indicating that the repeated high doses of the peptide caused non-specific effects inducing anorexia. We also tested several other behavioral parameters like locomotion and exploratory time, grooming and resting time, using lower doses of PrRP that did not cause the adverse behavior. Moreover, we carried out locomotor and sensory motor activity tests at the doses that exerted the most pronounced effect on the food intake. None of these tests suggested any specific behavioral effect of PrRP. We conclude that the behavioral pattern induced by PrRP is likely to be different from those induced by many other neuropeptides affecting food intake in rats.     

非妊娠期子宫肌瘤与血清催乳素水平的临床探讨

目的:探讨非妊娠期血清催乳素水平与子宫肌瘤的关系。方法:采用放射免疫法(R IA)检测64例子宫肌瘤<4 cm患者的血清催乳素(PRL)。结果:子宫肌瘤≤2.5 cm者与正常对照组比较血清催乳素水平无显著性差异(P>0.05);子宫肌瘤≥2.6 cm者与正常对照组比较血清催乳素水平有显著性差异(P<0.05);子宫肌瘤≤2.5 cm者与子宫肌瘤≥2.6 cm者的血清催乳素水平有显著性差异(P<0.05)。结论:催乳素水平与子宫肌瘤的形成无明显关系,与子宫肌瘤较大有关。     

麦当乳通颗粒对哺乳期大鼠的催乳作用

目的研究麦当乳通颗粒对哺乳期大鼠的催乳作用。方法哺乳期大鼠灌胃给予不同剂量的麦当乳通颗粒后，观察其泌乳量、乳腺组织形态、血清泌乳素水平和垂体嗜酸性细胞数量的变化，以及对乳鼠生长的促进作用。结果麦当乳通颗粒可促进乳腺腺泡腔及导管扩大增生，减少乳腺小叶间脂肪结缔组织，明显增加垂体嗜酸性细胞数量和血清泌乳素水平，从而显著增加母大鼠的泌乳量，并显著提高其所喂养的仔鼠体重。结论麦当乳通颗粒对哺乳期大鼠有明显的催乳作用。