Dual excitatory and smooth muscle-relaxing effect of Sideritis montana extract on guinea-pig ileum.
The neuronal and smooth muscle effects of a methanol extract prepared from the air-dried flowering aerial parts of Sideritis montana L. (SME) was tested in vitro on Guinea-pig ileum. The chemical composition of the investigated extract was analysed by HPLC-MS, and chrysoeriol, chlorogenic acid and caffeic acid were detected as main constituents. The isolated organ assay showed that S. montana extract caused an immediate contraction and a more slowly developing inhibitory response in the ileum. The SME-induced contractions were strongly inhibited by the acetylcholine muscarinic receptor antagonist atropine (0.5 μM), but not by either the Na+ channel blocker tetrodotoxin (TTX; 0.5 μM) or the histamine H1 receptor antagonist chloropyramine (0.5 μM). Selective desensitization of capsaicin-sensitive neurons by the sensory neuron stimulant and blocker capsaicin did not influence the contractile effect of SME. As to the spasmolytic effect, SME inhibited the effects of electrical field stimulation, exogenous acetylcholine, and histamine. These smooth muscle-relaxing effects were reversible in 40 min by repeated renewals of the bathing solution.
Barbara
B
Tóth
Loránd
L
Bartho
Andrea
A
Vasas
Zsolt
Z
Sándor
Nikoletta
N
Jedlinszki
Gyula
G
Pinke
Judit
J
Hohmann
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002211:Capsaicin / Q000494:pharmacology; D005029:Ethylenediamines / Q000494:pharmacology; D005260:Female; D006168:Guinea Pigs; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D007082:Ileum / Q000187:drug effects*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009126:Muscle Relaxation / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D010276:Parasympatholytics / Q000494:pharmacology; D035261:Plant Components, Aerial / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018689:Sensory System Agents / Q000494:pharmacology; D031365:Sideritis / Q000737:chemistry*
D005029:Ethylenediamines; D006634:Histamine H1 Antagonists; D010276:Parasympatholytics; D010936:Plant Extracts; D018689:Sensory System Agents; C004664:chloropyramine; D001285:Atropine; D002211:Capsaicin