TY - JOUR
T1 - Different stimulatory effects of methylisogermabullone on the spontaneous contractility of rat gastrointestinal segments
AU - Kwon, Oh Deog
AU - Jeung, Seung Il
AU - Lee, Seoul
AU - Choi, Yeon Shik
AU - Choi, Bong Kyu
AU - Jung, Kyu Yong
PY - 2009/11
Y1 - 2009/11
N2 - Using rat gastrointestinal (GI) strips, this study investigated the stimulatory effects of methylisogermabullone (MIGB) purified from radish on the spontaneous contractility of GI smooth muscles and pharmacological mechanisms involved in the MIGB-induced GI contraction. MIGB at 30 μM differently regulated the tone and amplitude of spontaneous GI contractility according to the region (fundus through distal colon) and orientation (longitudinal and circular) of smooth muscles: a significant increase in both tone and amplitude of spontaneous contraction in the ileum longitudinal and distal colon circular muscles and in amplitude only in the fundus, jejunum and distal colon longitudinal muscles. Pretreatment of ileum longitudinal muscles with atropine (0.5 μM) or 4-DAMP (0.5 μM) significantly inhibited the acetylcholine (ACh, 1 μM)- and MIGB (30 μM)-stimulated contraction, and methoctramine (0.5 μM) also obviously reduced the tone and amplitude increased by ACh and MIGB, respectively. In the presence of methysergide (1 μM), pretreatment of ileum longitudinal muscles with both ondansetron (0.1 μM) and GR113808 (0.1 μM) significantly inhibited the contraction stimulated by 5-HT (10 μM), but not by MIGB. Taken together, it is concluded that MIGB differently regulates the spontaneous contractility (tone and/or amplitude) of GI segments according to the region of gut and orientation of smooth muscles, and these contractile responses of GI tracts to MIGB are likely mediated, at least, by activation of acetylcholinergic M2 and M3 receptors.
AB - Using rat gastrointestinal (GI) strips, this study investigated the stimulatory effects of methylisogermabullone (MIGB) purified from radish on the spontaneous contractility of GI smooth muscles and pharmacological mechanisms involved in the MIGB-induced GI contraction. MIGB at 30 μM differently regulated the tone and amplitude of spontaneous GI contractility according to the region (fundus through distal colon) and orientation (longitudinal and circular) of smooth muscles: a significant increase in both tone and amplitude of spontaneous contraction in the ileum longitudinal and distal colon circular muscles and in amplitude only in the fundus, jejunum and distal colon longitudinal muscles. Pretreatment of ileum longitudinal muscles with atropine (0.5 μM) or 4-DAMP (0.5 μM) significantly inhibited the acetylcholine (ACh, 1 μM)- and MIGB (30 μM)-stimulated contraction, and methoctramine (0.5 μM) also obviously reduced the tone and amplitude increased by ACh and MIGB, respectively. In the presence of methysergide (1 μM), pretreatment of ileum longitudinal muscles with both ondansetron (0.1 μM) and GR113808 (0.1 μM) significantly inhibited the contraction stimulated by 5-HT (10 μM), but not by MIGB. Taken together, it is concluded that MIGB differently regulates the spontaneous contractility (tone and/or amplitude) of GI segments according to the region of gut and orientation of smooth muscles, and these contractile responses of GI tracts to MIGB are likely mediated, at least, by activation of acetylcholinergic M2 and M3 receptors.
KW - Gastrointestinal contractility
KW - Methylisogermabullone
KW - Muscarinic receptor
KW - Rat
UR - http://www.scopus.com/inward/record.url?scp=72049127516&partnerID=8YFLogxK
U2 - 10.1007/s12272-009-2115-z
DO - 10.1007/s12272-009-2115-z
M3 - Article
C2 - 20091276
AN - SCOPUS:72049127516
SN - 0253-6269
VL - 32
SP - 1613
EP - 1620
JO - Archives of Pharmacal Research
JF - Archives of Pharmacal Research
IS - 11
ER -