Effects of Activation and Blockade of Serotonin 5-HT1A Receptors on the Immune Response in Rats Selected for Different Levels of Aggressiveness

The present study examines the effects of serotonin (5-HT) 1A receptor ligands on humoral im-mune response in two rat lines selected for over 75 generations for the enhancement or elimination of aggression. Activation of presynaptic 5-HT1A receptors with a low dose of the selective 5-HT1A receptor agonist 8-OH-DPAT (0.1 mg/kg) or the blockade of postsynaptic 5-HT1A receptors with the antagonist WAY-100635 (1.0 mg/kg) did not affect the numbers of IgM-antibody forming cells (IgM-AFC) in the spleen of highly aggressive rats, which were characterized by higher immune responsiveness compared to nonaggressive line. On the other hand, the same doses of 8-OH-DPAT and WAY-100635, as well as a higher dose of 8-OH-DPAT (1.0 mg/kg), which is known to activate postsynaptic 5-HT1A receptors, produce immunostimulation in nonaggressive rats. However, only the highest dose of 8-OH-DPAT (5.0 mg/kg) was able to cause immunosuppression in nonaggressive rats that was mainly dependent on stimulation of postsynaptic 5-HT1A receptors. In contrast to nonaggressive rats, the dose of 1.0 mg/kg 8-OH-DPAT was sufficient to produce a decrease in the numbers of IgM-AFC in highly aggressive rats. Thus, pharmacological activation of pre- and postsynaptic 5-HT1A receptors, as well as the blockade of postsynaptic 5-HT1A receptors, produced different effects on the immune response in two lines of rats selected for high level of aggression or its absence. These data may have implications for more efficient treatments of a number of mental disorders associated with abnormal aggression.

Augmentative effect of tetrandrine on pentobarbital hypnosis mediated by 5-HT_(1A) and 5-HT_(2A/2C) receptors in mice

It has been reported that augmentative effect of tetrandrine on pentobarbital hypnosis in mice may be related to serotonergic system. The present study was undertaken to investigate the interaction of tetrandrine and different 5-HT receptors on pentobarbital-induced sleep by using the loss-of-righting reflex method. The results showed that augmentative effect of tetrandrine on pentobarbital hypnosis in mice were potentiated by the p-MPPI （5-HT1A receptor antagonist） （1 mg/kg, i.p.） and ketanserin （5-HT2A/2C receptor antagonist） （1.5 mg/kg, i.p.）, respectively. Pretreatment with either 8-OH-DPAT （5-HT1A receptor agonist） （0.1 mg/kg, s.c.） or DOI （5-HT2A/2C receptor agonist） （0.2 mg/kg, i.p.） significantly decreased pentobarbital-induced sleep time, and tetrandrine （60 mg/kg, i.g.） significantly reversed this effect. These results suggest that both the 5-HTLA and 5-HT2A/2C subfamily may be involved in the potentiating mechanism of tetrandrine＇s effects on pantobarbital hypnosis.

Rivastigmine Restores 5-HT_1AReceptor Levels in the Hippocampus of Olfactory Bulbectomized Mice

Rivastigmine, a dual acetylcholinesterase and butyrylcholinesterase inhibitor, is used for symptomatic treatment of patients with mild to moderately severe dementia in Alzheimer’s disease (AD) patients. In the present study, we found that 5-HT1A receptor (5-HT1AR) is downregulated, whereas 5-HT2A receptor (5-HT2AR) is upregulated in the hippocampal dentate gyrus (DG) and CA1 region by olfactory bulbectomy (OBX) in mice. Furthermore, chronic treatment with rivastigmine (1.0 mg/kg) for 2 weeks starting 2 weeks after OBX operation restored the decreased 5-HT1AR and the increased 5-HT2AR levels. To determine whether cholinergic receptor stimulation by rivastigmine is involved in the rivastigmine-induced regulation of 5-HTR levels, we treated the mice with mecamylamine (2.5 mg/kg), or atropine (5.0 mg/kg) with rivastigmine (1.0 mg/kg) once a day for 2 weeks. Notably, the rivastigmine-induced 5-HT1AR upregulation was eliminated by mecamylamine but not by atropine treatments. On the other hand, the restored 5-HT2AR level by rivastigmine was not affected by either mecamylamine or atropine. Treatment with 8-OH-DPAT, a selective 5-HT1AR agonist improved the decreased 5-HT1AR and the increased 5-HT2AR levels in OBX mice. On the other hand, treatment with TCB-2, a potent 5-HT2AR agonist had no effects on the 5-HT1AR and 5-HT2AR dysregulation in OBX mice. Taken together, nicotinic acetylcholine receptor (nAChR) stimulation mediates rivastigmine-induced upregulation of 5-HT1AR. Therefore, we speculate that the increased ACh levels by rivastigmine can stimulate nAChR located on serotonergic nerve terminals and stimulate 5-HT1AR by the enhanced 5-HT release in the hippocampus. The 5-HT1AR stimulation likely mediates the improvement of 5-HT1AR levels as auto-receptor in OBX hippocampus.

Inhibition of 5-HT_3 Receptors-activated Currents by Cannabinoids in Rat Trigeminal Ganglion Neurons

This study investigated the modulatory effect of synthetic cannabinoids WIN55,212-2 on 5-HT3 receptor-activated currents (I5-HT3) in cultured rat trigeminal ganglion (TG) neurons using whole-cell patch clamp technique. The results showed that: (1) The majority of examined neurons (78.70%) were sensitive to 5-HT (3–300 μmol/L). 5-HT induced inward currents in a concentration-dependent manner and the currents were blocked by ICS 205-930 (1 μmol/L), a selective antagonist of the 5-HT3 receptor; (2) Pre-application of WIN55,212-2 (0.01–1 μmol/L) significantly inhibited I5-HT3 reversibly in concentration-dependent and voltage-independent manners. The concentra-tion-response curve of 5-HT3 receptor was shifted downward by WIN55,212-2 without any change of the threshold value. The EC50 values of two curves were very close (17.5±4.5) mmol/L vs. (15.2±4.5) mmol/L and WIN55,212-2 decreased the maximal amplitude of I5-HT3 by (48.65±4.15)%; (3) Neither AM281, a selective CB1 receptor antagonist, nor AM630, a selective CB2 receptor antagonist reversed the inhibition of I5-HT3 by WIN55,212-2; (4) When WIN55,212-2 was given from 15 to 120 s before 5-HT application, inhibitory effect was gradually increased and the maximal inhibition took place at 90 s, and the inhibition remained at the same level after 90 s. We are led to concluded that-WIN55,212-2 inhibited I5-HT3 significantly and neither CB1 receptor antagonist nor CB2 receptor antagonist could reverse the inhibition of I5-HT3 by WIN55,212-2. Moreover, WIN55,212-2 is not an open channel blocker (OCB) of 5-HT3 receptor. WIN55,212-2 significantly inhibited 5-HT-activated currents in a non-competitive manner. The inhibition of I5-HT3 by WIN55,212-2 is probably new one of peripheral analgesic mechanisms of WIN55,212-2, but the mechanism by which WIN55,212-2 inhibits I5-HT3 warrants further investigation.

Changes of Serotonin （5-HT）, 5-HT2A Receptor, and 5-HT Transporter in the Sprague-Dawley Rats of Depression, Myocardial Infarction and Myocardial Infarction Co-exist with Depression

Background： To evaluate whether serotonin （5-HT）, 5-HT2A receptor （5-HT2AR）, and 5-HT transporter （serotonin transporter [SERT]） are associated with different disease states of depression, myocardial infarction （MI） and MI co-exist with depression in Sprague-Dawley rats. Methods： After established the animal model of four groups include control, depression, MI and MI with depression, we measured 5-HT, 5-HT2AR and SERT from serum and platelet lysate.Results： The serum concentration of 5-HT in depression rats decreased significantly compared with the control group （303.25 ± 9.99 vs. 352.98 ±13.73; P =0.000）, while that in MI group increased （381.78 ±14.17 vs. 352.98 ±13.73; P = 0.000）. However, the depression ＋ MI group had no change compared with control group （360.62 ±11.40 vs. 352.98 ±13.73; P = 0.036）. The changes of the platelet concentration of 5-HT in the depression, MI, and depression ＋ MI group were different from that of serum. The levels of 5-HT in above three groups were lower than that in the control group （380.40 ± 17.90, 387.75 ±22.28,246.40 ±18.99 vs. 500.29 ±20.91 ; P = 0.000）. The platelet lysate concentration of 5-HT2AR increased in depression group, MI group, and depression ＋ MI group compared with the control group （370.75 ±14.75,393.47 ±15.73,446.66 ±18.86 vs. 273.66 ±16.90; P= 0.000）. The serum and platelet concentration of SERT in the depression group, MI group and depression ＋ MI group were all increased compared with the control group （527.51 ±28.32, 602.02 ±23.32, 734.76 ±29.59 vs. 490.56 ±16.90; P 0,047, P = 0.000, P = 0.000 in each and 906.38 ±51.84, 897.33 ±60.34, 1030.17 ±58.73 vs. 708.62 ±51.15; P = 0.000 in each）. Conclusions： The concentration of 5-HT2AR in platelet lysate and SERT in serum and platelet may be involved in the pathway of MI with depression. Further studies should examine whether elevated 5-HT2AR and SERT may contribute to the biomarker in MI patients with depression.

New 3-(4-arylpiperazin-1-yl)-1-(benzo[b]thiophen-3-yl)-2-methylpropanol derivatives:Synthesis and evaluation for dual 5-HT1A/SSRI activities

A series of 3-（4-arylpiperazin-1-yl）-1-（benzo[b]thiophen-3-yl）-2-methylpropanol derivatives were designed and synthesized based on 5-HT1A/SSRI drugs design strategies.The synthesized compounds were evaluated for their dual 5-HT1A/5-HTT activities.

Effects of Estradiol on 5-HTsA and 5-HT2c Receptor Immunolabeling in Rat Hippocampus

Steroid hormones participate in the modulation of serotonergic transmission, including the regulation of synthetic and metabolic enzyme production, as well as receptor and transporter activity. The changes of 5-HT5A and 5-HT2c immunolabeling induced by steroids in the hippocampus ofovariectomized rats were studied in this work. Densitometric analysis in rat hippocampi were carried out for adjacent brain coronal immunolabeled sections after treatment with subcutaneous injections of vehicle, estradiol, progesterone or the combination of both steroids in ovariectomized rats. Exposure to estradiol and the combination of estradiol and progesterone significantly reduced the 5-HT5A-like immunosignal in the CA 1 region while progesterone did not induce changes. On the other hand, exposure to the combination of estradiol and progesterone or estradiol alone increased the 5-HT2c immunosignal in the same region. These results indicate that estradiol is involved in the discrete regulation of serotonin receptors 5-HT5A and 5-HT2c in rat hippocampus.

Role of 5-HT2A Receptors in Immunomodulation in Animal Models of Aggressive Behavior

Serotonin 5-HT2A receptors are playing an important role in the pathophysiology of aggressive behaviors and in the control of immune function. In the present study, we analyzed the effects of activation and blockade of 5-HT2A receptors with selective ligands on the immune response formation in animals with aggressive behaviors induced by genetic factors (rats selected for the increased aggressiveness toward human) or by chronic social stress (mice of the CBA/Lac strain engaged in 10 days of social confrontations). Activation of 5-HT2A receptors with DOI at 1.0 mg/kg reduced the immune response level both in aggressive rats and mice compared to the corresponding vehicle-treated groups, while DOI administration did not alter the immune reaction in nonaggressive animals. The blockade of 5-HT2A receptors with ketanserin at 1.0 mg/kg resulted in immunostimulation both in mice of the CBA strain not subjected to social stress (the controls) and in nonaggressive rats selected for elimination of aggressiveness. On the other hand, its administration to CBA mice demonstrating offensive aggression enhanced the immune reaction, while the same dose of ketanserin did not modify the immune response level in rats with genetic predisposition to the increased defensive aggression. Thus, our data suggest that the role of 5-HT2A receptors in immunomodulation depends on the specific type of aggression that may be taking into account in the treatment of some neuropsychiatric disorders with the antipsychotic drugs and antidepressants targeting 5-HT2A receptors.

Insights into the discovery of new 5-HT1A receptor ligands:receptor based pharmacophore

5-HT1A receptor is a crucial therapeutic target for the treatment of anxiety, depression, pain, etc. Design and preparation of potent 5-HT1A receptor ligands for drug discovery has attracted extensive attention in the past few years. In this paper, a three dimensional model of human 5-HT1A receptor was constructed by means of homology modeling. And the docking of MP349 to the receptor suggested a reliable binding mode for 5-HT1A receptor ligand. Based on this ligand-receptor binding mode, an elaborate receptor structure based pharmacophore model was established, which revealed many important features responsible for ligand and 5-HT1A receptor interactions. A virtual screening experiment verified the ability of this pharmacophore model to discover true 5-HT1A receptor ligand. The results of this research would provide important information for further optimizations of 5-HT1A receptor ligands and guide related new lead discoveries.

Altered serotonin metabolism in Takeda G protein-coupled receptor 5 knockout mice protects against diet-induced hepatic fibrosis

Background and aims:Diet-induced obesity and metabolic syndrome can trigger the progression of fatty liver disease to non-alcoholic steatohepatitis and fibrosis,which is a major public health concern.Bile acids regulate metabolic homeostasis and inflammation in the liver and gut via the activation of nuclear farnesoid X receptor(Fxr)and the membrane receptor Takeda G protein-coupled receptor 5(Tgr5).Tgr5 is highly expressed in the gut and skeletal muscle,and in cholangiocytes and Kupffer cells of the liver.Tgr5 is implicated in the mediation of liver and gut inflammation,as well as the maintenance of energy homeostasis.Here,we used a high fat,high fructose,and high sucrose(HFS)diet to determine how bile acid signaling through Tgr5 may regulate metabolism during the progression from fatty liver to non-alcoholic steatohepatitis and fibrosis.Materials and methods:Female C57BL/6J control wild type(WT)and Tgr5 knockout(Tgr5^(-/-))mice were fed HFS(high fat(40%kcal),high fructose,and 20%sucrose water)diet for 20 weeks.Metabolic phe-notypes were characterized through examination of bile acid synthesis pathways,lipid and cholesterol metabolism pathways,and fibrosis and inflammation pathways.Results:Tgr5^(-/-)mice were more glucose intolerant when fed HFS diet,despite gaining the same amount of weight as WT mice.Tgr5^(-/-)mice accumulated significantly more hepatic cholesterol and triglycerides on HFS diet compared to WT mice,and gene expression of lipogenic genes was significantly upregulated.Hepatic cholesterol 7alpha-hydroxylase(Cyp7a1)gene expression was consistently elevated in Tgr5^(-/-)mice,while oxysterol 7alpha-hydroxylase(Cyp7b1),sterol 27-hydroxylase(Cyp27a1),Fxr,and small heterodimer partner(Shp)were downregulated by HFS diet.Surprisingly,hepatic inflammation and fibrosis were also significantly reduced in Tgr5^(-/-)mice fed HFS diet,which may be due to altered se-rotonin signaling in the liver.Conclusions:Tgr5^(-/-)mice may be protected from high fat,high sugar-induced hepatic inflammation and injury due to altered serotonin metabolism.

Heat-Killed <i>Lactobacillus brevis</i>SBC8803 Induces Serotonin Release from Intestinal Cells

Previously, we reported that changes induced in autonomic neurotransmission in rats by Lactobacillus brevis SBC8803 may be mediated by serotonin 3 (5-HT3) receptors. In this study, we evaluated the effects of heat-killed L. brevis SBC8803 on serotonin (5-HT) releasing from intestinal cells. In the in vitro study, L. brevis SBC8803 stimulated 5-HT release from cultured rat endocrine RIN-14B cells (SBC8803 vs. sterile water;P in vivo study, 2 mg of heat-killed L. brevis SBC8803 was administered using a stomach sonde (feeding needle) to C57BL/6J mice. Analysis of plasma by ELISA showed gradually increase in 5-HT concentrations (0 min vs. 60 min;P ex vivo cultured intestinal loops composed of duodenum and part of the jejunum, from C3H/HeN and C57BL/6J male mice indicated that L. brevis SBC8803 effectively induced 5-HT release (SBC8803 vs. sterile water;P L. brevis SBC8803 may stimulate 5-HT release from mouse intestinal cells such as enterochromaffin cells.

Effects of Kaixin Powder on Expression of 5-HT Receptor in Hippocampus of Depressed Rats Induced by CUMS

Objective To observe the influence of Kaixin Powder on ethology,content of 5-HT in the hippocampus, expression of m RNA, and protein in 5-HT1 A and 5-HT2 A receptors in the hippocampus of depressed rats induced by chronic unpredictable mild stress（CUMS）. Methods Twenty-four male Wistar rats were randomly divided into blank,model, Trazodone, and Kaixin Powder groups, six rats in each group. In addition to the blank control group, other groups were established the depression model induced by CUMS combined with isolated feeding. At the same time, Trazodone group and Kaixin Powder group were treated with corresponding drugs for 3 weeks. After 3 weeks of administration, the rats were sacrificed, and a series of indexes were measured such as the contents of 5-HT, m RNA expression levels of 5-HT1 A and 5-HT2 A receptors, protein expression levels of 5-HT1 A and 5-HT2 A receptors, and so on. Results A series of indexes in the model group were decreased significantly such as the body weight growth, the sugar water intake, the score of Open Field Test, the content of5-HT in the hippocampus, expression of m RNA, and protein in 5-HT1 A receptor, while the expression of m RNA and protein in 5-HT2 A receptor were increased significantly.Compared with the model group, the indexes were ameliorated in Trazodone and Kaixin Powder groups. Kaixin Powder is better than Trazodone in decreasing the level of protein in 5-HT2 A receptor. Conclusion The result indicated that the depression performance of depressed rats induced by CUMS can be ameliorated by Kaixin Powder,and the mechanism maybe concerned with increasing the contents of 5-HT, exciting 5-HT1 A receptor, and antagonising 5- HT2 A receptor.

莉芙敏对去卵巢大鼠下丘脑视前区5-HT1AR和5-HT2AR表达的影响

目的:观察去卵巢大鼠应用黑升麻异丙醇提取物——莉芙敏(ICR)治疗1～4周后,免疫组化方法检测5-羟色胺1A受体(5-HT1AR)和5-HT2AR在大鼠下丘脑视前区表达的变化情况,为莉芙敏缓解围绝经期潮热症状的机制研究提供形态学依据。方法:雌性大鼠分为假手术组(Sham组)、去卵巢组(OVX组)、OVX后戊酸雌二醇治疗(OVX+E2)组和OVX后ICR治疗(OVX+ICR)组,每组40只。所有大鼠术后恢复2周后,再用相应的药物分别治疗1,2,3,4周,麻醉,心脏灌注,取脑,制作冰冻切片。免疫组化法观察各组大鼠下丘脑视前区5-HT1AR和5-HT2AR的表达。结果:①OVX组1～4周时大鼠下丘脑视前区5-HT1AR阳性细胞数量和吸光度均较同期Sham组增加;ICR和戊酸E2治疗1～4周后,OVX+E2组和OVX+ICR组大鼠下丘脑视前区室周带表达5-HT1AR的阳性细胞数量和吸光度均较同期OVX组减少。②下丘脑视前区中间带和外侧区5-HT2AR阳性细胞数量和吸光度的变化:OVX组大鼠,1～4周均较同期Sham组增加;ICR和戊酸E2治疗1周和2周后,OVX+E组和OVX+ICR组较同期OVX组增加;治疗3周和4周后,OVX+E2组和OVX+ICR组均较同期OVX组减少。结论:5-HT1AR和5-HT2AR在去卵巢大鼠下丘脑视前区的表达量均增加;ICR和戊酸E2治疗后,5-HT1AR在大鼠下丘脑视前区的表达量减少,而5-HT2AR在下丘脑视前区的表达先增多后减少。ICR可能通过调节下丘脑视前区体温调节中枢的5-HT1AR和5-HT2AR的表达,以缓解围绝经期的潮热症状。

1-[2-(2-Methoxyphenylthio) benzyl]-4-arylpiperazines derivatives:Synthesis and evaluation for dual 5-HT_(1A)/SSRI activities

A series of 1-[2-（2-methoxyphenylthio） benzyl]-4-arylpiperazines derivatives was designed and synthesized based on 5-HT1A/ SSRI drugs design strategies. The synthesized compounds were evaluated for their dual 5-HT1A/5-HTT activities. 2007 Ai Jun Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

1-(N-(2-(2-Methoxyphenylthio)benzyl)-N-methylamino-3-aryloxypropan-2-ols:Synthesis and evaluation for dual 5-HT_(1A)/SSRI activities

A series of 1-（N-（2-（2-methoxyphenylthio）benzyl）-N-methylamino-3-aryloxypropan-2-ols derivatives were designed and synthesized based on 5-HT1A/SSRI drugs design strategies. The synthesized compounds were evaluated for their dual 5-HT1A/ 5-HTT activities. 2007 Ai Jun Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

N-(2-(2-Methoxyphenylthio)benzyl)-2-aryloxyethylamines:Synthesis and evaluation for dual 5-HT_(1A)/SSRI activities

The design, synthesis and biological evaluation of N-（2-（2-methoxyphenylthio） benzyl）-2-aryloxyethyl amines with dual 5-HT1A/SSR/activities are reported. Compound 8e displays the best dual activities and is a promising lead compound for further SAR studies.

Arylpiperazine derivatives of diphenylsulfide:Synthesis and evaluation for dual 5-HT_(1A)/SSRI activities

The design, synthesis and biological evaluation of a novel series of arylpiperazine derivatives of diphenylsulfide with dual 5- HT1A/SSRI activities are reported. The target compounds exhibit low to moderate 5-HT transporter affinity and moderate to high 5- HT1A affinity, Compound 13a shows moderate dual activities and is a promising lead compound for further structure-activity relationships studies.

Prophylactic effects of asiaticoside-based standardized extract of Centella asiatica(L.) Urban leaves on experimental migraine: Involvement of 5HT1A/1B receptors

The present study aimed at evaluation of prophylactic efficacy and possible mechanisms of asiaticoside （AS） based standardized extract of Centella asiatica （L.） Urban leaves （INDCA） in animal models of migraine. The effects of oral and intranasal （i.n.） pretreatment of INDCA （acute and 7-days subacute） were evaluated against nitroglycerine （NTG, 10 mg·kg^-1, i.p.） and bradykinin （BK, 10 μg, intra-arterial） induced hyperalgesia in rats. Tail flick latencies （from 0 to 240 rain） post-NTG treatment and the number of vocalizations post-BK treatment were recorded as a measure of hyperalgesia. Separate groups of rats for negative （Normal） and positive （sumatriptan, 42 mg.kg ^-1, s.c.） controls were included. The interaction of 1NDCA with selective 5-HT1A, 5-HT1B, and 5-HTI D receptor antagonists （NAN-190, Isamoltane hemifumarate, and BRL-15572 respectively） against NTG-induced hyperalgesia was also evaluated. Acute and sub-acute pre-treatment of INDCA [10 and 30 mg.kg^-1 （oral） and 100 μg/rat （i.n.） showed significant anti-nociception activity, and reversal of the NTG-induced hypera｜gesia and brain 5-HT concentration decline. Oral pre-treatment with INDCA （30 mg·kg ^-1, 7 d） showed significant reduction in the number of vocalization. The anti-nociceptive effects of INDCA were blocked by 5-HTIA and 5-HT1B but not 5-HT1D receptor antagonists. In conclusion, 1NDCA demonstrated promising anti-nociceptive effects in animal models of migraine, probably through 5-HT1A/1B medicated action.

一种^(99)Tc^m标记的5-HT_(1A)受体显像剂的合成与标记

合成了一种99Tcm标记的5-HT1A受体显像剂。该显像剂先由二硫二氮与6-溴己酰氯结合,再与2-(1-哌嗪)苯甲醚结合,经还原、脱保护反应得到标记前体,再对前体进行99Tcm标记。标记率达90%以上,薄层层析测得标记物放化纯度大于95%。

5-HT_(1A)受体蛋白在PC12细胞膜转运的动态变化

目的在神经元样PC12活细胞上进行实时、可视和定量研究5-羟色胺1A受体的时空分布、膜转运和信号传导机制。方法运用RT-PCR方法获得小鼠5-HT1A基因,并插入到pEGFP-N1真核表达载体中。采用阳离子脂质体方法将质粒转染至PC12细胞和HEK293细胞中,通过G418筛选出稳定表达5-HT1A-EGFP的PC12细胞系。运用激光共聚焦成像系统观察活细胞中5-HT1A-EGFP的表达情况,利用光漂白荧光恢复(FRAP)技术在PC12细胞膜局部漂白后观察5-HT1A-EGFP荧光蛋白在细胞膜上转运的情况。结果克隆所获得的小鼠5-HT1A基因是准确的。5-HT1A-EGFP蛋白清晰的分布于PC12和HKE293细胞膜上。通过FRAP技术观察到漂白区域的细胞膜在100s内有部分恢复,说明受体在细胞膜上发生转运。结论建立了稳定表达5-HT1A-EGFP融合蛋白的PC12细胞系,并利用活细胞成像和FRAP技术观察分析并证实了5-HT1A受体在PC12细胞的膜表面的表达和转运的动态变化。