Antihypertensive effects of isoquercitrin and extracts from Tropaeolum majus L.: evidence for the inhibition of angiotensin converting enzyme

Aim of the study

Previous studies have shown that the extracts obtained from Tropaeolum majus L. exhibit pronounced diuretic properties. In the present study, we assessed whether the hypotensive and/or antihypertensive mechanism of hydroethanolic extract (HETM), semi-purified fraction (TMLR) obtained from T. majus and the flavonoids isoquercitrin (ISQ) and kaempferol (KPF) can be mediated by their interaction with angiotensin converting enzyme (ACE).

Methods and methods

Firstly, to evaluate changes in mean arterial pressure (MAP), different groups of normotensive and spontaneously hypertensive rats (SHR) were orally and intraduodenally treated with HETM (10-300 mg/kg) and TMLR (12.5-100 mg/kg) and intravenously treated with ISQ and KPF being later anesthetized with ketamine (100 mg/kg) and xylazine (20 mg/kg). The left femoral vein and the right carotid artery were isolated, and polyethylene catheters were inserted for ISQ and KPF (0.5-4 mg/kg) administration and blood pressure recording, respectively. The plasmatic ACE activity was evaluated to indirect fluorimetry, in serum samples after orally treatment with HETM, TMLR, ISQ and KPF.

Results

The oral administration of the HETM and its TMLR significantly reduced, in a dose-dependent manner, the MAP in both normotensive and SHR. In addition, these preparations significantly decreased the MAP for up to 3 h after the administration of the extract. Additionally, the intravenous administration of ISQ, but not KPF, decreased MAP in rats. Otherwise, neither the extracts nor ISQ affected the heart rate. The oral administration of the HETM, TMLR or ISQ reduced ACE activity in serum samples at 90 min after administration. Finally, the intravenous administration of ISQ caused a significant reduction in the hypertensive response to angiotensin I, but not angiotensin II in normotensive rats.

Conclusion

Our results show that the hypotensive effects caused by the HETM, as well as by its TMLR, may be associated with the high levels of the flavonoid ISQ found in this plant. In addition, ISQ-induced hypotension in rats is an event dependent on the inhibition of angiotensin II generation by ACE.     

Mechanisms underlying the diuretic effects of Tropaeolum majus L. extracts and its main component isoquercitrin

Ethnopharmacological relevance

Previous studies have shown that the extracts obtained from Tropaeolum majus L., and its main compound isoquercitrin (ISQ), exhibit pronounced diuretic effects, supporting the ethnopharmacological use of this plant. The aim of this study was to evaluate the efficacy and mechanisms underlying the diuretic action of an ethanolic extract of Tropaeolum majus (HETM), its purified fraction (TMLR), and its main compound ISQ, in spontaneously hypertensive rats (SHR).

Materials and methods

The diuretic effects of HETM (300 mg/kg; p.o.), TMLR (100 mg/kg; p.o.), and ISQ (10 mg/kg; p.o.), were compared with classical diuretics in 7 days repeated-dose treatment. The urinary volume, sodium, potassium, chloride, bicarbonate, conductivity, pH and density were estimated in the sample collected for 15 h. The plasmatic concentration of sodium, potassium, urea, creatinine, aldosterone, vasopressin, nitrite and angiotensin converting enzyme (ACE) activity were measured in samples collected at the end of the experiment (seventh day). Using pharmacological antagonists or inhibitors, we determine the involvement of bradykinin, prostaglandin and nitric oxide (NO) in ISQ-induced diuresis. In addition, reactive oxygen species (ROS) and the activity of erythrocytary carbonic anhydrase and renal Na⁺/K⁺/ATPase were evaluated in vitro.

Results

HETM, TMLR and ISQ increased diuresis similarly to spironolactone and also presented K⁺-sparing effects. All groups presented both plasmatic aldosterone levels and ACE activity reduced. Previous treatment with HOE-140 (a B2-bradykinin receptor antagonist), or indomethacin (a cyclooxygenase inhibitor), or L-NAME (a NO synthase inhibitor), fully avoided the diuretic effect of ISQ. In addition, the 7 days treatment with ISQ resulted in increased plasmatic levels of nitrite and reducing ROS production. Moreover, the renal Na⁺/K⁺/ATPase activity was significantly decreased by ISQ.

Conclusion

Our results suggest that the mechanisms through ISQ and extracts of Tropaeolum majus increase diuresis in SHR rats are mainly related to ACE inhibition, increased bioavailability of bradykinin, PGI2, and nitric oxide, besides an inhibitory effect on Na⁺/K⁺-ATPase.     

Screening for in vivo (anti)estrogenic and (anti)androgenic activities of Tropaeolum majus L. and its effect on uterine contractility

Ethnopharmacological relevance

Tropaeolum majus L. (Tropaeolaceae) is a medicinal herb popularly used in Brazil for treatment of inflammatory and cardiovascular diseases. Despite some published data on its efficacy, there are still few toxicological data describing the safety of this plant. The aim of this study was to evaluate the (anti)estrogenic and (anti)androgenic activity of the hydroethanolic extract obtained from Tropaeolum majus L. (HETM), as well as its possible effects on uterine contractility.

Materials and methods

Three experimental protocols were performed, (a) uterotrophic assay, (b) Hershberger assay and (c) an ex vivo test to investigate the effects of maternal administration of HETM on uterine contractility at the end of pregnancy. In all protocols three doses of the HETM were administered to Wistar rats: 3, 30 and 300 mg/kg.

Results

In vivo tests for detection of (anti)androgenic and (anti)estrogenic activities did not show any significant alterations. Similarly, no alterations were observed on uterine contractility induced by oxytocin and arachidonic acid.

Conclusions

HETM was unable to produce (anti)estrogenic or (anti)androgenic activities in the short-term in vivo screening assays performed. In addition, there was no evidence that HETM can affect uterine contractility following gestational exposure of rats.     

Natriuretic and diuretic effects of Tropaeolum majus (Tropaeolaceae) in rats

Tropaeolum majus L. (Tropaeolaceae), popularly known as “chaguinha”, is well recognized in Brazilian traditional medicine as diuretic agent, although no scientific data have been published to support this effect.     

Serviceberry [Amelanchier alnifolia (Nutt.) Nutt. ex. M. Roem (Rosaceae)] leaf extract inhibits mammalian α-glucosidase activity and suppresses postprandial glycemic response in a mouse model of diet-induced obesity and hyperglycemia

Ethnopharmacological relevance

The use of medicinal plants for the treatment of diseases usually comes from the belief that they present low toxicity due their natural origin. However, it is necessary a toxicological and pharmacological evaluation for these plants. Tropaeolum majus is a medicinal plant used in popular medicine to treat several diseases, including cardiovascular disorders, urinary tract infections and asthma. Even though several studies proved its therapeutic effects, there are few toxicological studies with this species.

Aim of the study

The present study was carried out to evaluate the subchronic toxicity of the hydroethanolic extract obtained from leaves of T. majus (HETM) in Wistar rats.

Material and methods

Male and female Wistar rats received three doses of HETM (75, 375 and 750 mg/kg) for 28 days. After the treatments biochemical, hematological and histopathological parameters were analyzed.

Results

No significant alterations in the animal's body weight gain, relative organs weight, serum biochemical analysis, hematological or histopathological analyses of liver, kidneys and spleen were observed.

Conclusions

These results demonstrate the absence of subchronic toxicity due to oral treatment with HETM for 28 days in Wistar rats. However, other toxicological studies are necessary to evaluate the total safety of this plant.     

Anti-ulcerogenic activity and isolation of the active principles from Sambucus ebulus L. leaves

Ethnopharmacological relevance

Sambucus ebulus L. has a very prominent place in Turkish folk medicine. Leaves of the plant are practiced externally to relieve rheumatic pain, to treat abscess, for wound healing and internally against hemorrhoids and stomachache. In a previous work, aqueous extract of the leaves was shown to possess potent antiulcerogenic activity on water immersion and immobilization-induced stress ulcer model in rats. This study aims to investigate the antiulcerogenic activity profile of the plant on various in vivo peptic ulcer models and gastric biochemical parameters and through bioassay-guided processing to isolate the active constituent (s) and to elucidate its structure.

Materials and methods

Among the subextracts obtained by successive solvent extractions from the MeOH extract of the leaves, the butanol subextract exerted significant antiulcerogenic activity against water-immersion and immobilization-induced stress ulcer model in rats as the bioassay model. This subextract was then subjected to successive chemical separation techniques (precipitation, column chromatography based on ion-exchange, silica gel and sephadex) and the activity of each fraction/subfraction was tested using the same bioassay model. After determination of active principles, further studies were performed on the active subextract by using various in vivo test models (ethanol-, serotonin-, pyloric ligation-induced ulcerogenesis) in rats as well as biochemical methods for the evaluation of antiulcerogenic potential.

Results

Bioassay-guided fractionation procedures yielded two flavonol glycosides as the active antiulcerogenic principles. The structures of these compounds were elucidated as isorhamnetin-3-O-monoglycoside and quercetin-3-O-monoglycoside by using ¹H, ¹³C-NMR, and FAB-MS techniques.

Conclusion

This study has proven the folkloric use of Sambucus ebulus leaves for the treatment of gastric ailments in Turkish folk medicine. The antiulcerogenic activity of the two flavonol glycosides isolated in the present study was not previously reported elsewhere.     

大八角根化学成分研究

采用硅胶、Sephadex LH-20、ODS及制备型HPLC等多种色谱技术,从大八角根中分离得到10个化合物,根据理化性质及波谱数据（MS,¹H,¹³C-NMR）分析分别鉴定为cycloparviflorolide（1）,cycloparvifloralone（2）,tashironin（3）,tashironin A（4）,anislactone A（5）,anislactone B（6）,pseudomajucin（7）,syringaldehyde（8）,methyl-4-hydroxy-3,5-dimethoxybenzoate（9）和（E）-3-methoxy-4,5- methylenedioxycinnamic alchol（10）。其中化合物 1~4,8~10 为首次从该植物中分离得到。在1.0×10^-5 mol·L^-1下,在LPS刺激小鼠小胶质细胞释放NO抑制模型上,化合物 5,6 抑制率分别为75.31%,53.7%。     

Inhibitory effects of Chelidonium majus extract on atopic dermatitis-like skin lesions in NC/Nga mice

Aim of the study

Chelidonium majus (CM) has traditionally been used for treatment of various inflammatory diseases including atopic dermatitis (AD). However its action on atopic dermatitis (AD) is unclear. Therefore, we investigated the effect of CM on AD using NC/Nga mice as an AD model.

Materials and methods

The effect of CM on 1-chloro-2,4-dinitrobenzene (DNCB) induced NC/Nga mice was evaluated by examining skin symptom severity, itching behavior, ear thickness, levels of serum immunoglobulin E (IgE), tumor necrosis factor-α (TNF-α), and interlukin-4 (IL-4), skin histology.

Results

The CM significantly reduced the total clinical severity score, itching behavior, ear thickness and the level of serum IgE in AD mouse model. CM not only decreased TNF-α but also IL-4.

Conclusion

These results suggest that CM may be a potential therapeutic modality for AD.     

Diuretic and anti-diuretic activities of the ethanol and aqueous extracts of Alismatis rhizoma

Ethnopharmacological relevance

Alismatis rhizoma or Alisma orientale (Zexie in Chinese), the dried rhizome of Alisma orientale Juzepzuk (Alismataceae), is a well-known traditional Chinese medicine and is used as an agent for diuresis and for excreting dampness in Asia and Europe. In this paper, we report the diuretic activities of the ethanol extract (EE) and the aqueous extract (AE) of A. rhizoma (AR).

Materials and methods

The EE and AE were orally administered to rats. The urinary excretion rate and pH, and electrolyte excretion were measured in the urine of saline-loaded rats.

Results

The results showed that EE could increase the urine output at 2.5, 5 and 10 mg/kg doses but decrease the urine output at 20, 40 and 80 mg/kg doses compared with the control group. The 5 and 10 mg/kg doses of EE increased the urine electrolyte excretion, but the effects on Na⁺/K⁺ values were too weak to reach statistical significance. The Na⁺ excretion and Cl⁻ excretion were markedly decreased with the 20, 40 and 80 mg/kg doses of EE, but the effect on K⁺ excretion was notably slight. All of the tested doses of AE produced an increase in urinary excretion, but the increase did not reach statistical significance.

Conclusions

This study identified that EE but not AE presents a notable diuretic effect, and EE had diuretic and anti-diuretic effects, which appears to be related to the sodium–chloride co-transporter in the renal distal convoluting tubule. This study demonstrated for the first time that the EE of AR has a dual effect on renal function, including promotion of diuretic activity at lower doses and inhibiting diuretic activity at higher doses, and the AR dose should be given more attention in clinical applications. This study will play a critical and guiding role in the dosing of AR as a diuretic drug in clinical applications.     

Diuretic activity of some Smilax canariensis fractions

Ethnopharmacological relevance

Smilax canariensis is an endemic species of the Canary Islands, popularly known as “Zarzaparrilla sin espinas”. The rhizome, leaves and stem of this species has wide use in folk medicine practice on the islands, where they are habitually employed as diuretic.

Aim of the study

In this paper we report on the diuretic activity in experimental animals of several fractions of the methanol extract of this species.

Materials and methods

Four fractions of the methanol extract of the rhizomes, leaves and stem of Smilax canariensis (50 and 100 mg/kg), Furosemide and Hydrochlorotiazide (10 mg/kg), were orally administered to laboratory animals to evaluate their diuretic activity. Water excretion rate, pH, conductivity, and content of Na⁺, K⁺ and Cl⁻ were measured in the urine of saline-loaded mice.

Results

All the studied extracts showed an interesting increase of the diuresis, although the n-buthanol (27%; p < 0.05) and ethyl acetate extract (35%; p < 0.01), at 100 mg/kg p.o., showed the most interesting diuretic activity, which suggested that this diuretic effect is associated with the compounds contained in the fractions of intermediate polarity (ethyl acetate and n-butanol), decreasing in the most extreme apolar and polar sub-extracts (dichloromethane and methanol: water respectively). The increase in diuresis produced by these two extracts was very close to the values of Hydrochlorothiazide (32%) or Furosemide (39%), used as reference diuretics.

Conclusions

These data, together with previous results on the aqueous and methanol extracts, reaffirm assertions made regarding the effectiveness of the extracts of this plant against urinary pathologies in the Canary Islands folk medicine.     

Diuretic activity and acute oral toxicity of Palicourea coriacea (Cham.) K Schum

Aim of the study

Palicourea coriacea (Cham.) K Schum, is an endemic plant used in the Midwestern Region of Brazil, popularly known as “douradinha do campo” and “congonha do campo”. This plant has been used in traditional medicine for several ailments, especially to treat kidney diseases. Since no formal studies on the biological activities and medicinal properties of the ethanolic extract of Palicourea coriacea (PCEE) have been carried out previously, the present study represents the first research into the efficacy of this plant as a diuretic agent employing laboratory rats as test animals.

Materials and methods

For diuretic activity evaluation we assayed three doses of PCEE (20, 40 and 80 mg/kg) and measurement of the urinary volume and electrolytes (Na⁺, K⁺) concentration were taken. The acute oral toxicity of PCEE was investigated according to OECD Guideline 423.

Results

The oral administration of a single dose of PCEE significantly increased the urinary volume in 24 h. Additionally, the treatment with PCEE increased, in a dose-dependent manner, the excretion of both, Na⁺ and K⁺. No sign of toxicity was observed in the animals.

Conclusions

The present study confirmed the ethnopharmacological use of Palicourea coriacea as a diuretic agent in the experimental condition tested here. Additionally, this work supports the importance of the preservation of local knowledge as well as the conservation of Brazilian biodiversity.     

菊花-槐花总黄酮的制备工艺及质量控制

目的:优化菊花-槐花总黄酮的制备工艺,并建立总黄酮及指标成分的质量控制方法。方法:采用单因素试验和正交设计考察菊花-槐花总黄酮的制备和纯化工艺,分别用比色法和高效液相色谱法测定总成分和指标成分。结果:菊花-槐花总黄酮的制备工艺为处方药材用14倍量的70%乙醇回流提取3次,每次1 h;提取液浓缩至0.5 g.mL-1,以质量比1∶0.5的比例上样HPD 600大孔树脂柱,先用10倍树脂体积的蒸馏水洗去杂质,再用5倍树脂体积的80%乙醇解吸附;收集洗脱液,浓缩至干后,即得菊花-槐花总黄酮。经比色法测定工艺产品的总黄酮质量分数为64.98%~66.79%;经HPLC法测定其指标成分木犀草素-7-O-葡萄糖苷质量分数为5.87%~6.93%,芦丁质量分数为14.09%~16.62%。结论:含水乙醇提取结合大孔树脂柱纯化是制备菊花-槐花总黄酮的有效方法,比色法和高效液相色谱法可用于其质量控制。     

Diuretic, anti-inflammatory, and analgesic activities of the ethanol extract from Cynoglossum lanceolatum

Ethnopharmacological relevance

Cynoglossum lanceolatum Forsk. (Boraginaceae) has been used in folk medicine in china to treat acute nephritis, periodontitis, acute submandibular lymphadenitis, snake bite, etc. However, there have been no scientific reports in the modern literature on the diuretic, anti-inflammatory and analgesic effects of this plant. The objective of this study is to evaluate the above activities of the Cynoglossum lanceolatum extract (CLE) in animals.

Materials and methods

The diuretic effect of CLE was assessed in rats and rabbits. The anti-inflammatory activity was evaluated using fresh egg white-induced paw edema in rats, carrageenan-elicited paw edema in adrenalectomized rats, and dimethylbenzene-induced inflammation in mice. The analgesic action was estimated in mice using the acetic acid-induced writhing test and the hot-plate test. In addition, the acute oral toxicity of CLE was studied in mice.

Results

CLE strikingly and dose-dependently increased urine output of rats and rabbits, suppressed fresh egg white-induced paw edema in rats and carrageenan-elicited paw edema in adrenalectomized rats, reduced dimethylbenzene-induced ear edema in mice, inhibited the writhing response in mice, but did not increased reaction time of mice in the hot-plate test. No death of mice was observed when orally administered CLE up to 12 g/kg.

Conclusions

These findings propose that CLE has evident diuretic, anti-inflammatory, and non-central analgesic activities. Furthermore the anti-inflammatory action does not rely on endogenetic glucocorticoids regulated by hypothalamo-pituitary-adrenal axis. On the other hand, CLE also shows a favorable safety.     

Chelidonium majus is not hepatotoxic in Wistar rats,in a 4 weeks feeding experiment

Aim of the study

Aerial parts of Chelidonium majus L. (Papaveraceae family) are traditionally used in the treatment of gallstones and dyspepsia, however several cases of hepatotoxicity are reported. In this work we evaluated the effects on liver function of a C. majus extract, obtained from the herbal material responsible for one case of hepatotoxicity.

Materials and methods

Experiments were performed in Wistar rats, after oral administration of doses corresponding to 1.5 and 3 g/(kg day) of herbal drug, for 2 or 4 weeks. Blood samples were collected to perform biochemical analysis, whereas liver samples were used for histomorphological and immunohistochemical examination along with the determination of oxidative stress parameters.

Results

No significant modification in animal body weight, food consumption, enzyme activities, hepatic histomorphology and MDA formation, at either time or dosage level. Conversely, C. majus induced a slight but significant decrease of GSH levels and SOD activity, especially at the high dose.

Conclusions

Our study suggests that C. majus, at doses about 50 and 100 times higher than those generally used in humans, does not alter hepatic function. However, the reduction in GSH levels and SOD activity suggests particular attention in use of C. majus or its preparations in situations (pharmacological treatments, physio-pathological conditions, etc.) that can compromise liver function.     

Anti-inflammatory effect of Inonotus obliquus, Polygala senega L., and Viburnum trilobum in a cell screening assay

Aim of the study

The purpose of the study was to assess the anti-inflammatory effects of the mushroom Inonotus obliquus (Chaga), Polygala senega (Senega) and Viburnum trilobum (Cranberry) bark extract fractions from locally produced materials in lipopolysaccharide (LPS) induced murine macrophage RAW 164.7 cells.

Materials and methods

Four fractions from each of the three extracts were obtained: (80% ethanol extracted; Fa), (water-soluble polysaccharide fraction; Fb), (Polyphenolic fraction; Fc) and (ETOAc/H₂O extracted fraction; Fd). These extract fractions were tested in the cell screening system at 50,100 and 500 μg/ml for their ability to inhibit LPS induced inflammatory cytokines IL-1β, TNFα and IL-6. Supernatants from LPS alone treated cells were used as control. The cytokines in the cell culture supernatants following treatments with extract fractions were quantified by ELISA method, using 96 well ELISA plates.

Results

All fractions of the extracts significantly inhibited (p < 0.05) the levels of IL-1β, IL-6 and TNFα except the polyphenolic Fc fraction of Senega which showed an increased production of IL-6. Furthermore, each fraction showed a dose-dependant anti-inflammatory effect. Nitric oxide production was not affected by cranberry and senega, while Chaga significantly reduced NO production in murine macrophage cell assay.

Conclusions

These results demonstrate that the extracts obtained from the root of Polygala senega L., bark of Viburnum trilobum, and the mushroom Inonotus obliquus possess anti-inflammatory properties when tested in a RAW 264.7 macrophage cell system.     

Anthelmintic activity of Chenopodium album (L) and Caesalpinia crista (L) against trichostrongylid nematodes of sheep

AIM OF THE STUDY: The present study was carried out to determine the anthelmintic activity of Caesalpinia crista (L.) (Fabaceae) seed kernel and Chenopodium album (L.) (Chenopodiaceae) whole plant in order to justify their traditional use in veterinary medicine. MATERIALS AND METHODS: In vitro anthelmintic activity of crude aqueous methanolic extract (AME) of both the plants was determined using mature Haemonchus contortus and their eggs in adult motility assay and egg hatch test, respectively. In vivo anthelmintic activity was evaluated in sheep naturally infected with mixed species of gastrointestinal nematodes by administering crude powder (CP) and AME in increasing doses (1.0-3.0 g/kg). RESULTS: Both plants exhibited dose- and time-dependent anthelmintic effects by causing mortality of worms and inhibition of egg hatching. Caesalpinia crista (LC50=0.134 mg/mL) was found to be more potent than Chenopodium album (LC50=0.449 mg/mL) in egg hatch test. In vivo, maximum reduction in eggs per gram (EPG) of faeces was recorded as 93.9 and 82.2% with Caesalpinia crista and Chenopodium album AME at 3.0 g/kg on day 13 and 5 post-treatment, respectively. Levamisole (7.5 mg/kg), a standard anthelmintic agent, showed 95.1-95.6% reduction in EPG. CONCLUSIONS: These data show that both Caesalpinia crista and Chenopodium album possess anthelmintic activity in vitro and in vivo, thus, justifying their use in the traditional medicine system of Pakistan.     

连翘及其主要有效成分槲皮素体外抗人巨细胞病毒的实验研究

目的:研究连翘及其主要有效成分槲皮素体外抗人巨细胞病毒作用和细胞毒性。方法:用细胞病变法和MTT法,检测连翘、槲皮素抗人巨细胞病毒的最大无毒浓度、最小有效浓度和治疗指数,并与更昔洛韦进行比较。结果:更昔洛韦、连翘及槲皮素的最大无毒浓度分别为10,30,30 mg.L-1,最小有效浓度分别为10,30,0.3 mg.L-1,治疗指数分别为1,1,100。结论:槲皮素抗HCMV效果大大高于更昔洛韦和连翘,细胞毒性与连翘相同、比更昔洛韦低。连翘尤其是槲皮素具有良好的体外抗人巨细胞病毒(HCMV)效果,有望成为临床抗HCMV的药物,值得进一步深入研究。     

糯米藤中黄酮类化学成分研究

目的:对糯米藤的化学成分进行研究。方法:运用多种色谱方法进行分离纯化,根据理化性质和波谱数据鉴定化合物的结构。结果:从糯米藤95%乙醇提取物的乙酸乙酯萃取部分中分离得到12个化合物,分别签定为异鼠李素(1),山柰酚(2),槲皮素(3),异鼠李素-3-O-α-L-鼠李糖苷(4),山柰酚-3-O-α-L-鼠李糖苷(5),异鼠李素-3-O-β-D-葡萄糖苷(6),山柰酚-3-O-β-D-葡萄糖苷(7),槲皮素-3-O-α-L-鼠李糖苷(8),槲皮素-3-O-β-D-葡萄糖苷(9),异鼠李素-3-O-芸香糖苷(10),山柰酚-3-O-芸香糖苷(11)和槲皮素-3-O-芸香糖苷(12)。结论:所有化合物均为首次从该属植物中分离得到。     

Diuretic activity of the ethanol and aqueous extracts of the surface layer of Poria cocos in rat

Ethnopharmacological relevance

Poria cocos Wolf (Polyporaceae) is a well-known traditional East-Asian medicinal fungus. the epidermis (“Fu-Ling-Pi” in Chinese) of the sclerotia is used as a diuretic. This study was conducted to evaluate of ethanol extract (EE) and aqueous extract (AE) of the diuretic activity of Fu-Ling-Pi in saline-loaded rats.

Material and methods

The EE and AE were orally administered to rats. Urinary excretion rate, pH and electrolyte excretion were measured in the urine of saline-loaded rats.

Results

Urinary excretion rates were significantly increased by the EE. The three doses of AE only produced a slight increase urinary output. The EE had little or no effect on K⁺ excretion, but did indeed induce a notable excretion of Na⁺, that was in agreement with the urinary excretion. The three doses of AE produced an increase Na⁺ and K⁺ excretion, but did not arrive at statistical significance.

Conclusions

The present study confirmed that the not aqueous but ethanol extracts of the epidermis of Poria cocos presents a remarkable diuretic effect.