Endothelium independent calcium channel blocking pathways mediate antihypertensive effect of morus nigra.

Present study was conducted to validate the folkloric claims of morus nigra l. (moraceae) using invasive blood pressure measuring and ex vivo vasorelaxant experimental techniques. Intravenous administration of mn. Aq in 0.01-30 mg/kg doses caused significant decrease in mean arterial pressure and heart rate in fructose-induced hypertensive rats. It also showed relaxation in high k+ [80 mm] and pe (1µm) mediated aortic contraction with ec50 1.25 and 3.72mg/ml values, respectively. Vaso-relaxant effect of mn.aq was partially blocked in presence of l-name with ec50, 5.32mg/ml value, but showed concentration dependent significant inhibition of ligand gated and voltage gated ca+2 channels and intracellular ca+2 release, similar to verapamil. Findings of current study designate that aqueous fraction of m. Nigra possesses antihypertensive activity with concentration-dependent vaso-relaxant effect predominantly mediated through endothelial-independent calcium channel blocking pathways accompanied by partial involvement of endothelium-dependent nos mediated relaxation.

Ipomoea hederacea Jacq.: A plant with promising antihypertensive and cardio-protective effects.

ETHNOPHARMACOLOGICAL RELEVANCE: Seeds of Ipomoea hederacea Jacq. (family: Convolvulaceae) are traditionally used to treat high blood pressure and cardiac diseases. AIM OF THE STUDY: Present study was conducted to validate the traditional claim and explore the possible mechanism(s) of antihypertensive effects of I. hederacea. MATERIALS AND METHODS: Aqueous-ethanolic extract and activity based fractions of I. hederacea were evaluated using invasive blood pressure measuring technique, isolated tissue experiments, fructose induced hypertension/metabolic syndrome and biochemical analysis.Phytochemical analysis of active fraction was performed with aim to identify chemical composition of I. hederacea seeds. LC-MS analysis was also performed to identify the compounds proposed to be present in active fraction of I. hederacea seeds. RESULTS: Crude extract/fractions of I. hederacea showed dose (0.01-100 mg/kg) dependent significant hypotensive effect in normotensive anesthetized rats, similar to verapamil (0.01-30 mg/kg). Pretreatment with hexamethonium and atropine mediated no significant changes in hypotensive effect of butanol fraction of I. hederacea (Ih.Bn) at 3 mg/kg dose. However, a significant decrease in the hypotensive effect of Ih.Bn 3 mg/kg (-34.82 ± 3.36%; p < 0.05) was observed in the presence of L-NAME (20 mg/kg). Similarly, Ih.Bn (3 mg/kg) showed no significant effect on angiotensin-II response. However, response of phenylephrine (45.60 ± 9.63%; p < 0.05) and dobutamine (18.25 ± 2.10%; p < 0.01) was significantly decreased in the presence of Ih.Bn 3 mg/kg. Ih.Bn also exhibited dose dependent (0.01-100 mg/kg) antihypertensive effect in fructose induced hypertensive rats, similar to verapamil (0.01-30 mg/kg). Concomitant treatment with Ih.Bn (3, 10 and 30 mg/kg) for six weeks showed a dose dependent profound protection with significant (p < 0.01) effect at 30 mg/kg against fructose induced basal mean arterial pressure (142.2 ± 4.62 mmHg). Ih.Bn did not significantly change response of PE, Ang-II and Epi was observed in invasive and ex vivo techniques. However, Ih.Bn significantly (p < 0.01; p < 0.001) prevented against decrease in vascular response of acetylcholine in anesthetized rats and in isolated aorta of rat. A significant dose dependent decrease in triglyceride and glucose level (p < 0.001), and increase in HDL level (p < 0.05) was observed in Ih.Bn treated groups. Results of LC-MS analysis of Ih.Bn showed the presence of 24 compounds that belong to different chemical classes, including carboxylic acid, flavonoids, oligopeptides and tripeptide that are known to have antihypertensive and vasorelaxant properties. CONCLUSIONS: Results of present study indicate the presence of hypotensive/antihypertensive effect in crude extract/fractions of I. hederacea with most potent effect shown by butanol fraction (Ih.Bn), possibly mediated through α1 blocking, ß blocking and iNOS/cGMP stimulating activity.

A pharmacological evidence for the presence of antihistaminic and anticholinergic activities in Equisetum debile Roxb.

OBJECTIVE: The study was designed to evaluate possible antihistaminic and anticholinergic activities of Equisetum debile. MATERIALS AND METHODS: Effects of crude ethanolic (Ed.Eth) and effects of crude aqueous (Ed.Aq) extracts of E. debile were studied using isolated guinea pig ileum, rabbit jejunum, and rabbit trachea. Tissue responses were recorded using isotonic and isometric transducers, connected with PowerLab data acquisition system. RESULTS: A dose-dependent (0.1-0.3 mg/ml) rightward shift was demonstrated in histamine concentration-response curves. Whereas a complete relaxation of carbachol (1 µM)-induced contractions in isolated rabbit jejunum (3 mg/ml) and tracheal (10 mg/ml) preparations was observed, similar to dicyclomine at 1 and 3 µM, respectively. However, no significant difference between the effects of Ed.Eth and Ed.Aq was observed. CONCLUSION: Study provides pharmacological evidence for the presence of antihistaminic and anticholinergic activities in crude extracts of E. debile and also highlight its medicinal significance in the management of airway and gastrointestinal disorders.

A mechanistic evaluation of the traditional uses of Nepeta ruderalis in gastrointestinal and airway disorders.

CONTEXT: Nepeta ruderalis Buch.-Ham. (Lamiaceae), locally known as Badranj Boya, is an aromatic herb used traditionally as an antispasmodic, antidiarrhoeal, and anti-asthamatic remedy. OBJECTIVE: Aqueous methanolic extract of N. ruderalis was studied to investigate its traditional uses. MATERIALS AND METHODS: Study was conducted from September 2015 to February 2016. In vitro spasmolytic and broncho-relaxant activity of crude extract of N. ruderalis (whole plant) was evaluated at 0.01-10 mg/mL final bath concentration in isolated rabbit jejunum and tracheal tissues, using PowerLab data acquisition system (Transonic Systems Inc., Ithaca, NY). In vivo antidiarrhoeal activity was evaluated in castor oil-induced diarrhoeal mice at the dose of 300 and 500 mg of crude extract orally. RESULTS: Crude extract of N. ruderalis completely relaxed spontaneously contracting, high K+ (80 mM) and carbachol (1 µM) induced contracted jejunum with an EC50 value of 5.85 (5.45-6.27), 4.0 (3.80-4.23) and 2.86 (2.48-3.29), similar to verapamil. Nr.Cr relaxed high K+ and carbachol induced contractions, at 5 and 10 mg/mL with an EC50 value of 2.37 (2.11-2.67) and 3.26 (2.9-3.67), respectively, and also displaced calcium concentration-response curves toward right at 0.1 and 0.3 mg/mL. Nr.Cr exhibited antidiarrhoeal protection at a dose of 300 and 500 mg/kg, similar to verapamil, whereas no acute toxicity signs were seen up to 5 g/kg in healthy mice. DISCUSSION AND CONCLUSION: Results suggest the presence of spasmolytic and broncho-relaxant effects in the crude extract of N. ruderalis, possibly mediated through calcium channel-blocking activity, providing the pharmacological basis for its traditional uses in gastrointestinal and airway disorders.