MEDICAL HYPOTHESES AND RESEARCH
VOL. 1, No. 2 / 3, July 2004


M. H. Boskabady [2004] Med Hypotheses Res 1: 139-147.


Relexant Effect of Portulaca Oleraceae on Guinea Pig
Tracheal Chains and its Possible Mechanism(s) of
Action

Mohammad H. Boskabady*, Mohammad T. Broushaki and
Mohammad R. Aslani

Department of Physiology (M.H.B., M.R.A.) and Pharmacology (M.T.B.), Ghaem Medical
Center, Mashhad University of Medical Sciences, Mashhad, Iran


Abstract. Therapeutic effect of portulaca oleraceae on respiratory diseases is
indicated in Iranian ancient medical books. The relaxant effect of this plant has also been
observed on smooth muscles in previous studies. In the present study, the relaxant effects
of boiled and aqueous extracts of portulaca oleraceae on tracheal chains of guinea pigs
were examined. The relaxant effects of 5 cumulative concentrations of boiled and aqueous
extracts (0.25, 0.5, 0.75, 1.0, and 1.25 w/v) in comparison with saline as a negative control
and 4 cumulative concentrations of theophylline (0.25, 0.5, 0.75, and 1.0 mM) were
examined by their relaxant effects in tracheal chains of guinea pig precontracted with 60
mM KCl (group 1, N = 6) and 10 µM methacholine under two different conditions: the
non-incubated tissues (group 2, N = 6) and tissues incubated with 1 µM propranolol plus 1
µM chlorpheniramine (group 3, N = 4). In group 1 experiments, only the two higher
concentrations of theophylline and boiled extract showed significant relaxant effects
compared to that of saline (P < 0.001 and P < 0.05 for theophylline and boiled extract,
respectively). The effects of two higher concentrations of theophylline in this group were
significantly greater than those of boiled and aqueous extracts (P < 0.01). However, in
group 2 and 3 experiments, both boiled and aqueous extracts and theophylline showed a
concentration-dependent relaxant effect compared to that of saline (P < 0.05 to P < 0.001).
There were no significant differences when comparing the relaxant effects of boiled and
aqueous extracts with those of theophylline in group 2 experiments. The relaxant effects of
boiled and aqueous extracts in group 1 were significantly lower than those of groups 2 and
3. However, the differences in he effects of extracts between group 2 and 3 and those of
theophylline in group 1 and 2 were not statistically significant. Taken together, these
results suggested a potent relaxant effect of portulaca oleraceae on the tracheal chains of
guinea pigs, and this effect was comparable to or even greater than theophylline at
concentrations used.


*Address all correspondence to: Professor M. H. BOSKABADY, DEPARTMENT OF
PHYSIOLOGY, GHAEM MEDICAL CENTER, MASHHAD UNIVERSITY OF
MEDICAL SCIENCES, MASHHAD. POSTAL CODE 91735, IRAN.
PHONE: 0098-511-8413579. FAX: 0098-511-8409612.


Full Text [PDF]