Schadenfreude or empathy? Children's emotional responses to the physical pain and pleasure of prosocial and antisocial others.

Adults' emotional reactions to the pain and pleasure of others are influenced by the moral character of those individuals. However, it remains unclear whether children's emotional responses also show such selectivity. To investigate this, we compared 4- to 8-year-old children's emotional responses to the physical pain and pleasure of prosocial versus antisocial puppets. In Study 1, children reported unhappiness after witnessing the pain of the prosocial and antisocial puppets but reported less unhappiness after witnessing the pain of the antisocial puppet. In Study 2, children reported happiness after witnessing the pleasure of both puppets but reported being less happy for the antisocial puppet. These results suggest that children are less likely to empathize with antisocial individuals. Meanwhile, children did not display Schadenfreude (pleasure at others' pain) or Gluckschmerz (displeasure at others' pleasure) toward antisocial individuals in our studies. Moreover, the selectivity of children's emotional responses disappeared after we manipulated the physical competence rather than the moral character of the puppets in Study 3. Our findings help to reveal the moral selectivity of emotional responses to others' pleasure and pain during early childhood.

Ferroptosis in Glaucoma: A Promising Avenue for Therapy.

Glaucoma, a blind-leading disease largely since chronic pathological intraocular high pressure (ph-IOP). Hitherto, it is reckoned incurable for irreversible neural damage and challenges in managing IOP. Thus, it is significant to develop neuroprotective strategies. Ferroptosis, initially identified as an iron-dependent regulated death that triggers Fenton reactions and culminates in lipid peroxidation (LPO), has emerged as a focal point in multiple tumors and neurodegenerative diseases. Researches show that iron homeostasis play critical roles in the optic nerve (ON) and retinal ganglion cells (RGCs), suggesting targeted treatments could be effective. In glaucoma, apart from neural lesions, disrupted metal balance and increased oxidative stress in trabecular meshwork (TM) are observed. These disturbances lead to extracellular matrix excretion disorders, known as sclerotic mechanisms, resulting in refractory blockages. Importantly, oxidative stress, a significant downstream effect of ferroptosis, is also a key factor in cell senescence. It plays a crucial role in both the etiology and risk of glaucoma. Moreover, ferroptosis also induces non-infectious inflammation, which exacerbate glaucomatous injury. Therefore, the relevance of ferroptosis in glaucoma is extensive and multifaceted. In this review, the study delves into the current understanding of ferroptosis mechanisms in glaucoma, aiming to provide clues to inform clinical therapeutic practices.

A chromosome-level genome assembly of Sesamia inferens.

The pink stem borer, Sesamia inferens (Walker), is a significant polyphagous pest historically restricted to regions south of N34° latitude. However, with changes in global climate and farming practices, the distribution of this moth has progressively exceeded its traditional limit of 34° N and encompassed most regions in North China. The genetic adaptations of S. inferens remain incompletely understood due to the lack of high-quality genome resources. Here, we sequenced the genome of S. inferens using PacBio and Hi-C technology, yielding a genome assembly of 865.04 Mb with contig N50 of 1.23 Mb. BUSCO analysis demonstrated this genome assembly has a high-level completeness of 96.1% gene coverage. In total, 459.72 Mb repeat sequences (53.14% of the assembled genome) and 20858 protein-coding genes were identified. We used the Hi-C technique to anchor 1135 contigs to 31 chromosomes, yielding a chromosome-level genome assembly with a scaffold N50 of 29.99 Mb. In conclusion, our high-quality genome assembly provided valuable resource that exploring the genetic characteristics of local adaptation and developing an efficient control strategy.

Rapid test to detect insecticide resistance in field populations of Spodoptera frugiperda (Lepidoptera: Noctuidae).

Introduction: The development of insecticide resistance in Spodoptera frugiperda populations is a serious threat to the crop industry. Given the spread of invasive resistant populations, prospective monitoring should be accelerated, and the development of diagnostic tools for rapid and accurate assessments of insecticide resistance is essential. Methods: First, the discriminating dose and diagnostic time of the kit were determined by the glass vial method based on a susceptible strain. Then, pests that were collected from field populations were used to determine their susceptibility to seven insecticides by using the diagnostic kit. Finally, the accuracy of the kit was verified based on correlation analyses and the likelihood of insecticide control failure was assessed. Results: Here, we describe a diagnostic kit that enables the rapid detection of resistance to chlorpyrifos, bifenthrin, deltamethrin, lambda-cyhalothrin, phoxim, chlorantraniliprole and chlorfenapyr within 1-2 h in S. frugiperda at diagnostic doses of 0.98, 0.84, 0.38, 1.64, 0.0082, 1.75 and 0.65 µg/cm2, respectively. The linear equation between mortalities under diagnostic doses and actual resistance ratios measured by the diet-overlay bioassay was determined. The high correlation indicates that the insecticide resistance levels diagnosed by the kit were consistent with the results of the diet-overlay bioassay. Moreover, we found a significant negative correlation between diagnostic mortality and the likelihood of control failure for bifenthrin (r = -0.899, p = 0.001), deltamethrin (r = -0.737, p = 0.024) and lambda-cyhalothrin (r = -0.871, p = 0.002). Discussion: The insecticide resistance diagnostic kit for S. frugiperda is a user-friendly tool (portable, short detection time). Its excellent performance qualifies the kit as a reliable screening tool for identifying effective insecticides in sustainable resistance management.

[Acupuncture-moxibustion treatment by stages based on the theory of "transformation of yin and yang" for premature ovarian insufficiency].

OBJECTIVE: To compare the efficacy between acupuncture-moxibustion treatment by stages and femoston for premature ovarian insufficiency (POI). METHODS: A total of 66 patients with POI were randomly divided into an observation group (33 cases, 3 cases dropped off) and a control group (33 cases, 2 cases dropped off). The patients in the observation group, based on the theory of "transformation of yin and yang", were treated with acupuncture-moxibustion by stages in the postmenstrual period, ovulatory period, premenstrual period and menstrual period, once every other day, 3 times a week. The patients in the control group were treated with oral administration of femoston (estradiol tablets/estradiol and dydrogesterone tablets, 1 tablet per day). Both groups were treated for 3 menstrual cycles. The ovarian function (serum follicle-stimulating hormone [FSH], luteinizing hormone [LH], estradiol [E2], anti-mullerian hormone [AMH] and antral follicle count [AFC]) and perimenopausal symptoms [modified Kupperman index (KI) scale score] were observed before and after treatment, and the menstrual improvement of the two groups was compared. RESULTS: Compared before treatment, the serum levels of FSH and LH were decreased (P<0.01), the levels of E2 were increased (P<0.01) in the two groups after treatment; the serum level of AMH and AFC in the observation group were increased after treatment (P<0.01). After treatment, the serum level of AMH and AFC in the observation group were higher than those in the control group (P<0.05). After treatment, there was no significant difference in the menstrual return rate and menstrual regularity rate between the amenorrhea patients of the two groups (P>0.05). After treatment, the modified KI scale scores in the two groups were reduced (P<0.01), and the modified KI scale score in the observation group was lower than that in the control group (P<0.05). CONCLUSION: Acupuncture- moxibustion treatment by stages based on the theory of "transformation of yin and yang" has similar efficacy with femoston in improving serum sex hormone level and menstrual symptoms in patients with POI, and has advantages in improving serum AMH level, AFC and perimenopausal symptoms.

Electrochemical Oxidation Enables Regioselective and Scalable α-C(sp3)-H Acyloxylation of Sulfides.

A highly selective, environmentally friendly, and scalable electrochemical protocol for the construction of α-acyloxy sulfides, through the synergistic effect of self-assembly-induced C(sp3)-H/O-H cross-coupling, is reported. It features exceptionally broad substrate scope, high regioselectivity, gram-scale synthesis, construction of complex molecules, and applicability to a variety of nucleophiles. Moreover, the soft X-ray absorption technique and a series of control experiments have been utilized to demonstrate the pivotal role of the self-assembly of the substrates, which indeed is responsible for the excellent compatibility and precise control of high regioselectivity in our electrochemical protocol.

A new pest management strategy: transforming a non-host plant into a dead-end trap crop for the diamondback moth Plutella xylostella L.

BACKGROUND: The use of trap crops can reduce the egg production of female Plutella xylostella in cruciferous vegetables and is an effective method for controlling this pest. To date, most of the trap plants that have been studied are cruciferous plants containing high concentrations of glucosinolates, which are more attractive to P. xylostella female adults. However, the application of these trap plants also has some limitations. Studies have shown that aqueous extracts of cruciferous plants can attract P. xylostella to lay eggs. In this study, we utilized the extract of Chinese kale to treat a non-host plant, the faba bean, and evaluated the possibility of using it as a dead-end trap plant for P. xylostella control. RESULTS: Plutella xylostella females laid significantly more eggs on faba beans that had been sprayed with the extract of Chinese kale rather than on Chinese kale itself. The first instar larvae of P. xylostella failed to survive on faba beans. Notably, the faba beans with the Chinese kale extract had the strongest attraction effect on P. xylostella females when placed 3 m away from the Chinese kale. Moreover, this attraction effect of faba beans on P. xylostella for oviposition lasted for up to 15 days. CONCLUSION: Faba bean plants sprayed with the aqueous extract of Chinese kale represent a potential dead-end trap plant for P. xylostella adults and their oviposition while being invariably deadly for their offspring. The present study provides a new proof of concept of using a non-cruciferous trap plant for P. xylostella management.

[Observation on therapeutic effect of electroacpuncture combined with penetrating moxibustion for postpartum pelvic organ prolapse].

OBJECTIVE: To compare the clinical therapeutic effect of electroacupuncture (EA) combined with penetrating moxibustion and biofeedback electrical stimulation on postpartum pelvic organ prolapsed (POP). METHODS: A total of 60 patients with POP who had delivery 6 weeks ago were randomized into an observation group and a control group, 30 cases in each one. In the observation group, EA was applied at Zigong (EX-CA 1), Ciliao (BL 32), Huiyang (BL 35), etc. while penetrating moxibustion was performed at acupoints of abdomen and lumbosacral region alternately every other day. In the control group, biofeedback electrical stimulation was provided. The treatment for 6 weeks was given once every other day, 3 times a week in both groups. Before treatment, after treatment and 6 months after delivery, pelvic floor muscle strength, pelvic organ prolapse quantification (POP-Q) evaluation and pelvic floor impact questionnaire short form-7 (PFIQ-7) were observed to assess the therapeutic effect. RESULTS: Compared before treatment, the sustained contraction and rapid contraction force of pelvic floor muscle after treatment and 6 months after delivery were increased in both of the two groups (P<0.05), and the changes in the observation group were larger than those in the control group (P<0.05). After treatment and 6 months after delivery, the POP degree in the observation group was alleviated to the control group (P<0.05). Compared before treatment, the scores of PFIQ-7 after treatment and 6 months after delivery were reduced in the two groups (P<0.05), and the changes in the observation group were larger than those in the control group (P<0.05). CONCLUSION: Electroacupuncture combined with penetrating moxibustion can strengthen the pelvic floor muscle contractility of patients with postpartum pelvic organ prolapse, and are superior to biofeedback electrical stimulation in improving the pelvic organ prolapse status and life quality.

[Efficacy of electroacupuncture combined with penetrating moxibustion for postpartum stress urinary incontinence].

OBJECTIVE: To compare the clinical effect differences between electroacupuncture (EA) combined with penetrating moxibustion and the biological feedback training of pelvic floor muscle for postpartum stress urinary incontinence (SUI). METHODS: Sixty patients of SUI who had delivery 42 days ago were randomly divided into an observation group and a control group, 30 cases in each one. The observation group was treated with EA and penetrating moxibustion. EA was applied at Ciliao (BL 32) and Huiyang (BL 35), combined with acupuncture at Qihai (CV 6), Zhongji (CV 3), Zigong (EX-CA 1), Zusanli (ST 36) and Sanyinjiao (SP 6); penetrating moxibustion was performed on abdomen and lumbosacral area. The control group was treated with biological feedback training of pelvic floor muscle. Both the groups were treated once every other day, 3 times per week for continuous 6 weeks. The International Consultation on Incontinence Questionnaire-Short Form (ICI-Q-SF), 1 h urinal pad test and pelvic floor muscle strength were tested before and after treatment; the efficacy was evaluated after treatment and at 6-month follow-up visit. RESULTS: Compared before treatment, the ICI-Q-SF score and 1 h urine leakage were significantly reduced after treatment in the two groups (P<0.01), and the reduction in the observation group was superior to that in the control group (P<0.05). Compared before treatment, the pelvic muscle strength of muscle fibers Ⅰand Ⅱ were significantly increased after treatment in the two groups (P<0.01), and the differences between the two groups had no statistical significance (P>0.05). After treatment, the cured rate and total effective rate were 70.0% (21/30) and 96.7% (29/30) in the observation group, which were superior to 33.3% (10/30) and 70.0% (21/30) in the control group (P<0.01); in the 6-month postpartum period, the cured rate and total effective rate were 63.3% (19/30) and 93.3% (28/30) in the observation group, which were superior to 30.0% (9/30) and 66.7% (20/30) in the control group (P<0.05). CONCLUSION: EA combined with penetrating moxibustion could improve the urinary control ability, relieve the symptoms of urinary incontinence and have a better long-term effect in patients with postpartum SUI, which is superior to biological feedback training of pelvic floor muscle.

Starvation Stress Causes Body Color Change and Pigment Degradation in Acyrthosiphon pisum.

The pea aphid, Acyrthosiphon pisum (Harris), shows body color shifting from red to pale under starvation in laboratory conditions. These body color changes reflect aphid's adaptation to environmental stress. To understand the color-shifting patterns, the underlying mechanism and its biological or ecological functions, we measured the process of A. pisum's body color shifting patterns using a digital imagery and analysis system; we conducted a series of biochemical experiments to determine the mechanism that causes color change and performed biochemical and molecular analyses of the energy reserves during the color shifting process. We found that the red morph of A. pisum could shift their body color to pale red, when starved; this change occurred rapidly at a certain stress threshold. Once A. pisum initiated the process, the shifting could not be stopped or reversed even after food was re-introduced. We also discovered that the orange-red pigments may be responsible for the color shift and that the shift might be caused by the degradation of these pigments. The carbohydrate and lipid content correlated to the fading of color in red A. pisum. A comparative analysis revealed that these reddish pigments might be used as backup energy. The fading of color reflects a reorganization of the energy reserves under nutritional stress in A. pisum; surprisingly, aphids with different body colors exhibit diverse strategies for storage and consumption of energy reserves.

Infection of Powdery Mildew Reduces the Fitness of Grain Aphids (Sitobion avenae) Through Restricted Nutrition and Induced Defense Response in Wheat.

In natural ecological systems, plants are often simultaneously attacked by both insects and pathogens, which can affect each other's performance and the interactions can be extended to higher trophic levels, such as parasitoids. The English grain aphid (Sitobion avenae) and powdery mildew (Blumeria graminis f. sp. tritici) are two common antagonists that pose a serious threat to wheat production. Numerous studies have investigated the effect of a single factor (insect or pathogen) on wheat production. However, investigation on the interactions among insect pests, pathogens, and parasitoids within the wheat crop system are rare. Furthermore, the influence of the fungicide, propiconazole, has been found to imitate the natural ecosystem. Therefore, this study investigated the effects of B. graminis on the biological performance of grain aphids and the orientation behavior of its endoparasitic wasp Aphidius gifuensis in the wheat system. Our findings indicated that B. graminis infection suppressed the feeding behavior, adult and nymph weight, and fecundity and prolonged the developmental time of S. avenae. We found that wheat host plants had decreased proportions of essential amino acids and higher content of sucrose following aggravated B. graminis infection. The contents of Pro and Gln increased in the wheat plant tissues after B. graminis infection. In addition, B. graminis infection elicited immune responses in wheat: increase in the expression of defense genes, content of total phenolic compounds, and activity of three related antioxidant enzymes. Moreover, co-infection of B. graminis and S. avenae increased the attraction to A. gifuensis compare to that after infestation with aphids alone. In conclusion, our results indicated that B. graminis infection adversely affected the performance of S. avenae in wheat through restricted nutrition and induced defense response. Furthermore, the preference of parasitoids in such an interactive environment might provide an important basis for pest management control.

Strategies used by two apterous strains of the pea aphid Acyrthosiphon pisum for passive dispersal.

Wingless forms of aphids are relatively sedentary, and have a limited ability to migrate or disperse. However, they can drop off hosts or walk away if disturbed, or their food quality or quantity become deteriorated. Earlier, we found that the pea aphid, Acyrthosiphon pisum (Harris, 1776), could use differed strategies to escape danger and locate new host plants. To determine the mechanisms behind the different strategies, we undertook a series of studies including the aphids' host location, energy reserves under starvation, glycogenesis, sugar assimilation, olfactory and probing behaviors. We found that in our controlled laboratory conditions, one strain (local laboratory strain) moved longer distances and dispersed wider ranges, and correspondingly these aphids assimilated more sugars, synthesized more glycogen, and moved faster than another strain (collected from Gansu Province, northwestern China). However, the latter strain could locate the host faster, probed leaves more frequently, and identified plant leaves more accurately than the former strain after they were starved. Our results explained how flightless or wingless insects adapt to fit biotic and abiotic challenges in the complex processes of natural selection.

Pea aphid Acyrthosiphon pisum sequesters plant-derived secondary metabolite L-DOPA for wound healing and UVA resistance.

Herbivores can ingest and store plant-synthesized toxic compounds in their bodies, and sequester those compounds for their own benefits. The broad bean, Vicia faba L., contains a high quantity of L-DOPA (L-3,4-dihydroxyphenylalanine), which is toxic to many insects. However, the pea aphid, Acyrthosiphon pisum, can feed on V. faba normally, whereas many other aphid species could not. In this study, we investigated how A. pisum utilizes plant-derived L-DOPA for their own benefit. L-DOPA concentrations in V. faba and A. pisum were analyzed to prove L-DOPA sequestration. L-DOPA toxicity was bioassayed using an artificial diet containing high concentrations of L-DOPA. We found that A. pisum could effectively adapt and store L-DOPA, transmit it from one generation to the next. We also found that L-DOPA sequestration verity differed in different morphs of A. pisum. After analyzing the melanization efficiency in wounds, mortality and deformity of the aphids at different concentrations of L-DOPA under ultraviolet radiation (UVA 365.0 nm for 30 min), we found that A. pisum could enhance L-DOPA assimilation for wound healing and UVA-radiation protection. Therefore, we conclude that A. pisum could acquire L-DOPA and use it to prevent UVA damage. This study reveals a successful co-evolution between A. pisum and V. faba.

Transport properties of puerarin and effect of extract of Radix Angelicae dahuricae on puerarin intestinal absorption using in situ and in vitro models.

The root of Angelica dahurica (Radix Angelicae Dahuricae, RAD), which contains coumarins and volatile oil as its main classes of active components, is often given in conjunction with Pueraria root (Radix Puerariae, RP), which contains the phytoestrogen puerarin. The two herbs are considered to be compatible 'herb-pairs' in traditional Chinese medicine. The present investigation investigates the absorption of puerarin from RP and the effect of the total coumarins and volatile oil from RAD on its absorption. The everted gut sac and single-pass intestinal perfusion methods were used, respectively. The results showed that the absorption of puerarin in the jejunum was significantly increased in the presence of the coumarins and/or volatile oil. The absorption rate constant (K(a)) of puerarin increased gradually until the concentration reached 160 µg · mL(-1), after which its absorption became saturated and the apparent permeability (P(app)) values significantly decreased. The results showed that the intestinal absorption mechanisms of puerarin involved active transportation processes and that puerarin is likely to be a substrate of P-gp because verapamil significantly affected its P(app) and K(a). The absorption of puerarin significantly increased (p < 0.01) when combined with RAD extracts, as shown by the increase in concentration of puerarin in blood from the hepatic portal vein, supporting the concept of RAD and RP as a compatible herb-pair.

[Intestinal absorption effect of Angelica dahurica extract on puerarin of puerariae Lobatae Radix].

OBJECTIVE: To study the effect of extractive Angelica dahutica on intestinal absorption of puerarin, the mechanism of the absorption enhancement of A. dahutica was investigated, providing a new thread of combinations of the Chinese herbal drugs. METHOD: Everted intestinal sac and in situ single pass perfusion were used to study the effect of gut absorption of puerarin solution containing the extractive A. dahurica as well as the influence of P-gp on the absorption of puerarin, and explore weather the extractive A. dahutica can enhance the absorption of puerarin and the mechanism of absorption of puerarin. RESULT: The puerarin could be absorbed at all of four intestinal segments with increaing absorption amount perunit as follows: ileum > colon > jejunum > duodenum. The absorption of puerarin in jejunum was significantly increased with the extractive A. dahutica in situ single pass perfusion of jejunum. The apparent permeability coefficient (Papp) and absorption rate constant (Ka) of puerarin in the jejunum were descreased gradually with higher concentrations, and the Papp with the Ka of jejunum solution containing the P-gp inhibitor of verapamil were increasing respectively 2.49, 2.60 (P < 0.001) than only the jejunum solution in absorption. The absorption of jejunum in pH 5.0, 6.8 were better than it in pH 7.4. CONCLUSION: The mechanism of absorption of jejunum was active absorption and was effected by P-gp. The extrative A. dahurica can enhance the absorption of the jejunum.

The absorption characterization effects and mechanism of Radix Angelicae dahuricae extracts on baicalin in Radix Scutellariae using in vivo and in vitro absorption models.

ETHNOPHARMACOLOGICAL RELEVANCE: Angelicae Dahurica(Hoffm.)Benth.&Hook.f.ex Franch.&Sav combined with Scutellaria baicalensis Georgi. has been widely used as herb-pairs in traditional Chinese medicine (TCM) to treat migraine headache and cataract, but the underlying compatibility mechanism of the two herbs remains unknown. AIM OF STUDY: In the present work, we investigated the additive or synergistic effects of absorption behavior of Radix Angelicae dahuricae extracts on baicalin, and the absorption-enhancing mechanism of Radix Angelicae dahuricae extracts on baicalin. MATERIALS AND METHODS: Total coumarins (Cou) and volatile oil (VO), as the two main components of Radix Angelicae dahuricae, were extracted by supercritical fluid extraction (SFE) further treated with liquid-liquid separation method. The absorption behavior was investigated by applying the everted gut sac technique and in situ single-pass intestinal perfusion method. RESULTS AND CONCLUSIONS: The results showed that both the Cou and the VO could improve the intestinal absorption of baicalin in vivo, and had synergistic action the enhanced absorption of baicalin. Since verapamil did not affect the P(app) and K(a) of baicalin significantly, we concluded that the absorption of Baicalin could not be an active transportation in dependent of P-glycoprotein-Mediated efflux systems. Based on intestinal absorption of drug studying was one of the efficacious methods to clarify the compatibility of principles of herb-pairs. The everted gut sac technique and in situ single-pass intestinal perfusion technique model were the effective methods to study the absorption of drug, the application of the animal model to investigating the absorption of herb-drug interactions or other relevant research purposes is envisioned.

[The enhancing effect of Angelica dahurica extracts on absorption of baicalin--the active composition of Scutellaria].

To explore the mechanism of the absorption enhancement of Angelica dahurica extract (Ade), the absorption mechanism of baicalin in the Scutcllaria water extraction as well as the effect of Angelica dahurica extract on absorption of baicalin were investigated. In order to determine the main absorption site, everted intestinal sac model was used to study the effect of Angelica dahurica extract on the absorption of baicalin at duodenum, jejunum, ileum and colon. In situ single pass intestinal perfusion model was performed to study the absorption of various concentrations of baicalin and the effect of Angelica dahurica extract on the absorption of baicalin at the main absorption site. To authenticate the consequence of perfusion by getting the blood from the hepatic portal vein and determine the concentration of the baicalin in the blood. The result showed that baicalin could be absorbed at all of the four intestinal segments with increasing absorption amount per unit as follows: ileum > colon > jejunum > duodenum. The absorption ofbaicalin in the duodenum significantly increased with Angelica dahurica extract, thus, duodenum was chosen to be the studying site. Apparent permeability values (Papp) and absorption rate constant (Ka) of baicalin in the duodenum increased gradually with higher concentrations. When the concentration of baicalin rises to a certain degree, the absorption increase had a saturable process, the absorption of baicalin may be an active transportation. Baicalin may be not a substrate of P-gp as verapamil which had not significantly affected the Papp and Ka of baicalin. The absorption of baicalin in the duodenum significantly increased (P < 0.01) in the two models with Angelica dahurica extract and the concentration of baicalin in the blood from the hepatic portal vein showed that the Angelica dahurica extract can increase the absorption of baicalin.

Correlation between synergistic action of Radix Angelica dahurica extracts on analgesic effects of Corydalis alkaloid and plasma concentration of dl-THP.

AIM OF STUDY: Yuanhu Zhitong prescription that consists of Corydalis yanhusuo and Radix Angelicae dahuricae has been used for the treatment of gastralgia, costalgia, headache and dysmenorrhea in Traditional Chinese Medicine. Our previous studies demonstrated that Corydalis alkaloid (CA, derived from the root of Corydalis yanhusu) had potent analgesic properties, and the total coumarins of Angelica dahurica (Cou) and volatile oil (VO) that derived from the root of Radix Angelicae dahuricae all could increase the analgesic effect of CA. The major objective of this paper was to investigate the mechanism that leading the analgesia of CA increased by Cou and (or) VO. MATERIALS AND METHODS: The relationship between analgesic effect of CA and the plasma concentration of Dl-tetrahydropalmatine (dl-THP, active component of CA) was assayed in mice writhing test. The CA (34, 68 and 134 mg/kg) reduced the nociception by acetic acid intraperitoneal injection in a dose-dependent manner, and there was a significant linear relationship between the analgesic effect of CA and the plasma concentration of dl-THP. Then the plasma concentration of dl-THP at different time intervals in rats after oral administration of CA, CA-Cou, CA-VO and CA-Cou-VO were examined by using HPLC. RESULTS AND CONCLUSION: The results indicated that Cou and (or) VO raised the plasma concentration of dl-THP prominently. In conclusion, the reason that Radix Angelica dahurica extracts reinforced the analgesic effects of Corydalis alkaloid was related to the improvement of the plasma concentration of dl-THP.