• Biomolecules & Therapeutics
• /
• v.9 no.4
• /
• pp.237-243
• /
• 2001

This study was attempted to investigate the effects of cromakalim (CRK), $K^{+}$ channel opener, and glibenclamide (GLY), $K^{+}$ channel blocker, on intestinal function of rabbit. CRK supressed the tension and spontaneous movement of intestinal strips. CRK enhanced the tension and spontaneous movement of strips induced by acetylcholine. Also the inhibiting effect of dopamine was potentiated by CRK. GLY augmented the tension, but did not affect the spontaneous movement of strips. GLY inhibited tension and spontaneous movements in intestinal strips induced by acetylcholine, GLY blocked the dopamine-induced attenuation of tension, but not the decrease of spontaneous movements in intestinal strips. The present studies suggest that $K^{+}$ channel opening suppresses intestinal movements, whereas it's blockade enhances intestinal movements in rabbit.abbit.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 2001.11a
• /
• pp.96-96
• /
• 2001

This study was attempted to investigate the effect of cromakalim(CRK). $K^{-}$ channel opener, and glibenclamide(GLY), $K^{-}$ channel blocker, on intestinal function of rabbit. CRK supressed the tension and spontaneous movement of intestinal strips. Such CRK strengthened the tension and spontaneous movement of strips potentiated by acetylcholine, whereas more attenuated those weakened by dopamine. GLY augmented the tension, did not affect to the spontaneous movement of strips. GLY inhibited the acetylcholine-potentiated responses of tension and spontaneous movements in intestinal strips. GLY blocked the weakened responses of tension, while did not affect to the dopamine-weakened responses of spontaneous movements in intestinal strips. The present studies suggest that $K^{-}$ channel opening suppresses intestinal movements, whereas it's blockade enhances intestinal movements in rabbit.abbit.

• The Journal of Korean Physical Therapy
• /
• v.14 no.4
• /
• pp.454-474
• /
• 2002

Vasoactive intestinal peptide (VIP) is a very potent dilatator and a nonadrenergic, noncholinergic (NANC) neurotransmitter or neuromodulator in the peripheral and the central nervous systems. The mechanisms of action of VIP were examined in aortic circular and in uterine longitudinal smooth muscle strips of the rat. The effects of sympathetic neurotransmitter were investigated in gastric and aortic circular muscle strips of the mouse and the rat. The effects of silver spike point, SSP, low frequency electrical stimulations of VIP, sympathetic neurotransmitter and $\beta$-endorphin were examined in plasma, serum and 24h urine from the healthy volunteer. In gastric smooth muscle strips from the mouse, adrenergic neurotransmitter norepinephrine was inhibitory effected, followed by caused phasic and tonic contraction to the, muscrine receptor agonist carbachol and acetylcholine, respectively. In urine from the healthy volunteer, both norepinephrine and epinephrine were significantly decreased in continue type and low frequency (3 Hz) of SSP electrical stimulations. The contractile responses to S-HT in uterine longitudinal smooth muscle strips of the rats were completely decreased by a VIP 1 $\mu$M. The contractile responses to PGF2$\alpha$ were not decreased by a VIP. In plasma and serum from the healthy volunteer, both VIP and $\beta$-endorphin were significantly increased in continue type and low frequency (3 Hz) of SSP electrical stimulations. Therefore, this study demonstrate that VIP has the capacity to relax vascular or gastric smooth muscles in part by stimulating the generation of NO, and silver spike point low frequency electrical stimulation has the capacity both to decrease sympathetic neurotransmitters and to increase VIP, $\beta$-endorphin.

• Journal of Pharmaceutical Investigation
• /
• v.7 no.1_4
• /
• pp.28-37
• /
• 1977

The pharmacological actions to methanol extract(PME) obtained from Plantaginis semen were examined in the rabbit. 1) PME, when administered into the vein of rabbit, produced the fall of blood pressure and stimulation of respiration. The former action was inhibited by atropine but the latter not affected by atropine. 2) PME caused contraction in both isolated intestinal and uterus strips, atropine blocked the contraction of intestinal strips while did not the uterus contraction. 3) PME decreased the heart rate of rabbit anesthetized with urethane. 4) PME elicited antidiuresis with doses ranging from 10mg/kg. The antidiuresis appeared to be related to the hemodynamic changes decreases in the renal plasma flow and glomerular filtration rate. Urinary sodium and potassium decrease in the renal plasma flow and glomerular filtration rate. Urinary sodium and potassium decrease in relation to the diminished filtration.

• Korean Journal of Veterinary Research
• /
• v.14 no.1
• /
• pp.33-40
• /
• 1974

It has been generally understood that the intestinal tracts are under the control of the autonomic nerves; the parasympathetics are excitatory and the sympathetics inhibitory. However, it is recently reported that the actions of these autonomic nerves in the newborn animals are shown to be different from those in the adult animals in some species. In order to elucidate the role of sympathetic innervation to the intestinal tracts, the effects of periarterial nerve stimulation were studied in the periarterial sympathetics-jejunum preparations of the chick and the effects of some autonomic drugs on the isolated muscle strips were also studied. The results obtained were as follows: 1. The periarterial stimulation in the periarterial sympathetics-jejunum preparation elicited the responses of three patterns; 1) contrcation followed by relaxation 2) contraction only 3) relaxation only. The excitatory response was most effective in the stimulus frequencies of 40 cps, whereas the inhibitory response was maximal in the stimulus frequencies of 30 cycle per second. 2. The excitatory response to the periarterial stimulation was not affected by the pretreatment with phenoxybenzamine, dibenamine, propranolol and atropine, whereas the inhibitory response was completely blocked by the pretreatment with phenoxybenzamine and propranolol. 3. In the periarterial syrnpathetics-jejunum preparation treated with reserpine, the periarterial stimulation evoked only contraction, and the contraction was not affected by the pretreatment with phenoxybenzamine, propranolol and atropine. 4. The administration of norepinephrine evoked a relaxation in the isolated jejunum muscle strips and the effect was completely blocked by the pretreatment with phenoxybenzamine. 5. The administration of isoproterenol produced a relaxation in the isolated jejunum muscle strips and the effect was not affected by pretreatment with phenoxybenzamine, whereas the effect was completely blocked by the pretratment with propranolol. 6) The administration of acetylcholine produced a marked contraction in the isolated jejunum muscle strips and the effect was completely abolished by the pretreatment of atropine. These experimental evidences indicate that the inhibitory response to the periarterial stimulation is due to adrenergic fibers and the excitatory response is due to neither adrenergic nor cholinergic component.

• The Korean Journal of Pharmacology
• /
• v.11 no.2
• /
• pp.41-46
• /
• 1975

The isolated strips of tortoise intestine are evaluated as a test organ for bioassay of prostaglandin $E_1$. This preparation responded highly sensitively to $PGE_1$ and $PGE_2$ in picogram concentration range. The mean slope and the value of precision index among the doses of 0.1, 0.3 and 0.5ng/ml in final concentration were 37.7 and 0.143, respectively. And this was relatively insensitive to different prostaglandins; $E_1/E_2{\gtrsim}1$, $E_1/A_2{\sim}50$ and $E_1/F_{2\alpha}{\sim}100$, and showed the dual responses to 5-hydroxytryptamine and histamine; initial contraction followed by relaxation. The dose-ratio inducing the relative equal contraction height for $PGE_1$, acetylcholine, caerulein, angiotensin and barium chloride was 0.4 : 50 : 25 : 10 : 100 in this order. These results suggest that the intestinal strips of the tortoise are suitable for bioassay of prostaglandin $E_1$ and $E_2$ between the doses of 0.1 and 1.0 ng/ml level in the tissue extracts.

• Korean Journal of Pharmacognosy
• /
• v.24 no.2
• /
• pp.140-152
• /
• 1993

This study was attempted to investigate the effect of Ganoderma lucidum extract on digestive system in experimental animals. Ganoderma lucidum water extract (GWE) was found to be promoted the charcol transport rate in the small intestine of mice. GWE exhibited the augmentation of spontaneus movement(motility) and contractile response(tension) in the ileum and colon strips of rabbit, and these action were inhibited by atropine. GWE given intraduodenaly(i.d.) exhibited the significant increase of gastric acid secretion in pylorus-ligated rats. GWE inhibited the formation of some experimental gastric ulcers(pylorus ligation ulcer i.d., indomethacin-induced ulcer p.o., i.d. and aspirin-induced ulcer p.o.) in rats, which are considered to relate to a protective action. GWE and EtOH extract(water soluble phase) were remarkably increase of bile excretion, when administration of i.d., intravenation(i.v.) and per os (p.o.) compared with normal-control group. GWE was observed antibacterial activity aginst several intestinal microoganisms and others bacteria in vitro test.

• Korean Journal of Pharmacognosy
• /
• v.25 no.3
• /
• pp.278-292
• /
• 1994

This study was attempted to investigate the effect of Machili Cortex extract(Machilus thunbergii Sieb. et Zucc. ) on digestive system in experimental animals. EtOH and MeOH extracts(E.E. and M.E.) were found to inhibit the charcoal transport rate in the small intestine of mice. E.E. exhibited the inhibition of spontaneous movement(motility) and tension in the ileum and colon strips of rabbit, and these actions were inhibited by action of acetylcholine. E.E. and M.E. given intraduodenaly(i.d.) exhibitied the significant decrease of gastric acid secretion in pylorus-ligated rats. E.E. and M.E. inhibited the formation of some experimental gastric ulcers(pylorus ligation-ulcer i.d., indomethacin-induced ulcer p.o. and aspirin-induced ulcer p.o. ) in rats, which are considered to relate to a protective action. E.E. and M.E. caused remarkable increase of bile excretion, compared with normal-control group, when adminstered through i.d., i.v. and p.o. The antibacterial activity against several intestinal microorganisms and other bacteria in vitro test was observed in the administration of E.E. and M.E.

• Korean Journal of Veterinary Research
• /
• v.25 no.1
• /
• pp.33-40
• /
• 1985

The inhibitory action of oxymetazoline on the spontaneous movements of isolated intestinal strips of the rabbit and the effects of antagonists upon the oxymetazoline actions were assessed with recordings through both isometric and isotonic transducers, and comparisons were made between both methods of recording. There were significant differences between the slopes of regression equations calculated from log dose response curves of oxymetazoline obtained from jejunum and those from ileum. But no difference was noted between both recordings either through isotonic transducer or through isometric transducer. The $ID_{50}$ of oxymetazoline obtained from the recording through isotonic transducer was $6.31{\times}10^{-7}M$ in jejunum and $3.16{\times}10^{-8}M$ in ileum. The recording through isometric transducer gave the values of $5.01{\times}10^{-7}M$ in jejunum and $1.07{\times}10^{-8}M$ in ileum. The $pA_2$-values of prazosin to oxymetazoline calculated from the recording through isotonic transducer were 8.13 in jejunum and 8.31 in ileum and the recording through isometric transducer gave the values of 7.29 and 8.26 in jejunum and ileum, respectively. The $pA_2$-values of phentolamine to oxymetazoline obtained from the recording through isotonic transducer were 8.18 in Jejunum and 9.31 in ileum and those from the recording through isometric transducer were 7.75 and 8.13 in jejunum and ileum, respectively. These results indicate that there are no significant differences between recordings either through isotonic transducer or through isometric transducer in assessing inhibitory responses of intestinal movement to certain drugs.

• Journal of Neurogastroenterology and Motility
• /
• v.24 no.4
• /
• pp.643-655
• /
• 2018

Background/Aims Irritable bowel syndrome (IBS) is a common disease characterized by intestinal dysmotility, the mechanism of which remains elusive. We aim to determine whether the high-affinity choline transporter 1 (CHT1), a determinant of cholinergic signaling capacity, modulates intestinal motility associated with stress-induced IBS. Methods A rat IBS model was established using chronic water avoidance stress (WAS). Colonic pathological alterations were evaluated histologically and intestinal motility was assessed by intestinal transit time and fecal water content (FWC). Visceral sensitivity was determined by visceromotor response to colorectal distension. RT-PCR, western blotting, and immunostaining were performed to identify colonic CHT1 expression. Contractility of colonic muscle strips was measured using isometric transducers. enzyme-linked immunosorbent assay was used to measure acetylcholine (ACh). We examined the effects of MKC-231, a choline uptake enhancer, on colonic motility. Results After 10 days of WAS, intestinal transit time was decreased and fecal water content increased. Visceromotor response magnitude in WAS rats in response to colorectal distension was significantly enhanced. Protein and mRNA CHT1 levels in the colon were markedly elevated after WAS. The density of CHT1-positive intramuscular interstitial cells of Cajal and myenteric plexus neurons in WAS rats was higher than in controls. Ammonium pyrrolidine dithiocarbamate partly reversed CHT1 upregulation and alleviated colonic hypermotility in WAS rats. Pharmacological enhancement of CHT1 activity by MKC-231 enhanced colonic motility in control rats via upregulation of CHT1 and elevation of ACh production. Conclusion Upregulation of CHT1 in intramuscular interstitial cells of Cajal and myenteric plexus neurons is implicated in chronic stress-induced colonic hypermotility by modulation of ACh synthesis via nuclear factor-kappa B signaling.