Antispasmodic effect of hydroalcoholic and flavonoids extracts of Dracocephalum kotschyi on rabbit bladder

Introduction: Dracocephalum kotschyi extract has antispasmodic activities on smooth muscle including ileum, uterus and trachea. The objective of this research was to investigate antispasmodic activity of hydroalcoholic and flavonoids extracts of D. kotschyi on rabbit bladder contractions. Methods: Rabbits were euthanized by carbon dioxide asphyxiation and the whole bladder was dissected out and immersed in the Tyrode’s solution. Longitudinal bladder strips were mounted vertically in an organ bath at 37°C and gassed continuously with O2 . Bladder strips were contracted with acetylcholine (ACh), KCl, or electrical field stimulation (EFS). Isotonic tension of the tissue was recorded before and after addition of hydroalcoholic or flavonoids rich extracts of D. kotschyi. Nifedipine and propantheline were used as standard drugs. Results: Standard drug propantheline, prevented bladder phasic contraction induced by ACh (1µM) without affecting KCl response. On the other hand, cumulative addition of nifedipine attenuated the tonic contractions induced by KCl (20mM) on bladder smooth muscle. Hydroalcoholic and flavonoids extracts of D. kotschyiat concentration ranges of 10-320 µg/ mL in a concentration dependent way inhibited bladder tonic contraction induced by KCl (n=6). Both extracts also in a concentration-dependent manner relaxed EFS and ACh-induced contractions (range, 20–1280 µg/mL) of bladder smooth muscle in vitro. Complete inhibition was achieved with the highest used concentrations of the extracts. The inhibitory effect of the extract was reversible following washing the tissues with fresh Tyrode’s solution. Conclusion: This study clearly demonstrated that D. kotschyi extracts were able to prevent contractions induced by ACh, KCl or EFS in isolated rabbit bladder. This means that people consuming this medicinal plant may face urinary retention which could be a problem for patients with prostate hypertrophy. On the other hand, this plant might be useful in patients with urinary incontinence. However, its usefulness must be assessed in the controlled clinical trials.

Comparative experimental study of 5-ALA and 5-ALA hexyl ester specific activity

A comparative experimental study of the specific activity of drugs based on 5-aminolevulinic acid (5-ALA) and its hexyl ester (5-ALA HE) was carried out. Their ability to induce the synthesis of photoactive protoporphyrin IX in the healthy tissues of the rabbit bladder when instilling the drug solutions at various concentrations has been estimated. It was shown that 5-ALA HE results in the induction and accumulation of PPIX in the rabbit bladder epithelium at much lower concentrations than 5-ALA. Thus, a significant increase in the fluorescence intensity in comparison with the control was achieved by instillation of 5-ALA HE solution in the rabbit’ bladder at a concentration of only 0.0001% (fluorescence intensity 2.20±0.60 a.u.), and for 5-ALA – only when using a solution at a concentration of 0.3% (fluorescence intensity 2.60±1.02 a.u.).