The actions of praziquantel and 1-methyladenine in guinea pig ileal longitudinal muscle

1979 ◽  
Vol 57 (12) ◽  
pp. 1460-1462 ◽  
Author(s):  
K. Jim ◽  
D. J. Triggle
Keyword(s):  
Smooth Muscle ◽  
Guinea Pig ◽  
Muscarinic Receptor ◽  
Longitudinal Muscle ◽  
Receptor Stimulation ◽  
Extracellular Concentration ◽  
Mechanical Responses ◽  
Channel Function ◽  
Longitudinal Smooth Muscle

Praziquantel (10−4 M) and 1-methyladenine (5 × 10−4 M) produced mechanical responses in guinea pig ileal longitudinal smooth muscle that were approximately 20% of those produced by muscarinic receptor stimulation. These responses were insensitive to tetrodotoxin and atropine but were dependent upon the extracellular concentration of Ca2+ and were abolished by D 600 at a concentration (10−6 M) which abolished the Ca2+-dependent muscarinic responses. Thus, praziquantel and 1-methyladenine may act as modulators of Ca2+ channel function in guinea pig ileal muscle.

scholarly journals Muscarinic-receptor stimulation enhances polyphosphoinositide breakdown in guinea-pig ileum smooth muscle

1984 ◽  
Vol 223 (2) ◽  
pp. 527-531 ◽  
Author(s):  
M C Sekar ◽  
B D Roufogalis
Keyword(s):  
Guinea Pig ◽  
Muscarinic Receptor ◽  
Longitudinal Muscle ◽  
Inositol Phosphates ◽  
Inositol Phosphate ◽  
Exchange Chromatography ◽  
Guinea Pig Ileum ◽  
Receptor Stimulation ◽  
Inositol 1 ◽  
Stimulation Of

Muscarinic-receptor stimulation by 0.1 mM-carbachol in longitudinal muscle of the guinea-pig ileum increases the incorporation of [3H]inositol into inositol-containing phospholipid. This effect was blocked by 16 microM-atropine. After 60 min incubation, carbachol increased the accumulation of total inositol phosphates 20-fold in the presence of 10 mM-Li+. Less than 20% of the total inositol phosphate corresponded to inositol 1-phosphate by ion-exchange chromatography, whereas of the remainder about two-thirds corresponded to inositol bisphosphate and one third to inositol trisphosphate. It is concluded that stimulation of muscarinic receptors in guinea-pig ileum enhances breakdown of polyphosphoinositides, suggesting that this may be a primary event associated with Ca2+ mobilization in the guinea-pig ileum.

The effect of ouabain on the guinea pig ileum longitudinal smooth muscle: 1. ATPase activities in a sarcolemma-enriched fraction prepared with the aid of divalent cation depletion of the intact muscle

1977 ◽  
Vol 55 (5) ◽  
pp. 1190-1196 ◽  
Author(s):  
M. R. James ◽  
B. D. Roufogalis
Keyword(s):  
Smooth Muscle ◽  
Guinea Pig ◽  
Atpase Activity ◽  
Divalent Cation ◽  
Microsomal Fraction ◽  
Longitudinal Muscle ◽  
Divalent Cations ◽  
Guinea Pig Ileum ◽  
Longitudinal Smooth Muscle ◽  
Intact Muscle

Depletion of divalent cations before fractionation of the longitudinal muscle of the guinea pig ileum yielded a sarcolemma-enriched microsomal fraction free of mitochondria. A major portion of the ATPase activity in the presence of Mg, Na, and K was due to stimulation by Na alone. A further small stimulation by K was demonstrated only in the presence of an activating factor from the 105 000 × g supernatant. Ouabain inhibited only the K activation and had no effect on the Na-stimulated Mg-ATPase.

The effects of Ca2+ antagonists on mechanical responses and Ca2+ movements in guinea pig ileal longitudinal smooth muscle

1979 ◽  
Vol 57 (4) ◽  
pp. 333-347 ◽  
Author(s):  
Lois B. Rosenberger ◽  
M. K. Ticku ◽  
D. J. Triggle
Keyword(s):  
Smooth Muscle ◽  
Guinea Pig ◽  
Mechanical Response ◽  
Muscarinic Agonist ◽  
Muscarinic Agonists ◽  
Tonic Component ◽  
Mechanical Responses ◽  
Longitudinal Smooth Muscle ◽  
A Site ◽  
Cellular Ca

The Ca2+ antagonists, Mn2+, Co2+, D 600 (α-isopropyl-α-[(N-methyl-N-homoveratryl)-γ-aminopropyl]-3,4,5-trimethoxyphenylacetonitrile), and BAY-1040 (2,6-dimethyl-3,5-dicarbo-methoxy-4-(2-nitro)phenyl-1,4-dihydropyridine) inhibited the response of guinea pig ileal longitudinal muscle to the muscarinic agonist CD (cis-2-methyl-4-dimethylaniinomethyl-1,3-dioxolane methiodide). With the exception of Tm3+ these agents were more effective against the tonic component of response.BAY-1040 was equally effective against phasic components of CD and K+ responses and, although more potent against tonic responses, also failed to discriminate between the tonic components of response to CD and K+. D 600, although less potent than BAY-1040, behaved similarly to BAY-1040 in failing to discriminate between CD and K+ responses. These data suggest that CD and K+ utilize identical, or at least very similar, sources of Ca2+ to sustain excitation-contraction coupling. The tonic component of the CD response showed an apparently cooperative dependence on Ca2+ concentration but D 600 and BAY-1040 behaved as powerful competitive antagonists against Ca2+ in both components of the response to CD (D 600, KI, 1.2 × 10−7 M (phasic), 9.8 × 10−9 M (tonic); BAY-1040, KI,1.8 × 10−8 M (phasic), 4.8 × 10−9 M (tonic)) with potencies similar to those found in other tissues where these agents inhibit membrane Ca2+ currents. The complete additivity of antagonism produced by combination of equieffective concentrations of Tm3+ and D 600 or BAY-1040 indicated that Tm3+ acts at a site distinct from that occupied by D 600 or BAY-1040. In contrast, D 600 and BAY-1040 appear to interact at a common site. No increase in total 45Ca uptake in the presence of 5 × 10−7 M CD could be detected at 0.5 min (phasic component) or 10 min (tonic component) but a significant decrease was found at 5 min and significant increases were found at later times (30 min, 60 min). However, an increase in the 45Ca cellular content, measured after washing in La3+ to remove superficial Ca2+ and to retain cellular Ca2+, could be detected at 0.5 and 10 min in the presence of 5 × 10−7 M CD, in tissues preequilibrated in 46Ca2+ for 60 min. This increase in cellular 46Ca was blocked by atropine, D 600, BAY-1040, and Tm3+ at concentrations that blocked mechanical response. It is concluded that the mechanical responses of guinea pig ileal longitudinal smooth muscle produced by muscarinic agonists or by KCl use Ca2+ that enters through Ca2+ channels similar to those described in other excitable tissues.

scholarly journals INFLUENCE OF ANTIBIOTICS ON THE MECHANICAL RESPONSES OF GUINEA-PIG ILEUM TO ACETYLCHOLINE AND HISTAMINE

1998 ◽  
Vol 13 (3) ◽  
pp. 145-147
Author(s):  
Andy Petroianu ◽  
JÚLIO WEINBERG
Keyword(s):  
Smooth Muscle ◽  
Side Effects ◽  
Guinea Pig ◽  
Guinea Pig Ileum ◽  
Mechanical Responses ◽  
Longitudinal Smooth Muscle ◽  
Before And After ◽  
Muscle Responses

The side effects of antibiotics have been extensively described during the last decades, however, their role on digestive motility must be better investigated. Following a line of research, the influence of penicillin, chloranfenicol tetracycline and gentamicine on longitudinal smooth muscle responses to acetylcholine and histamine were studied on guinea-pig ileum. There were no differences between the responses before and after the addition of each antibiotic. Further investigations must be performed in order to find a possible influence of antibiotics on digestive motility.

Amphibian toxins from the skin of Bufo regularis have inhibitory effect on electrically invoked contractile response and bimodal effects on tone of longitudinal muscle of guinea pig ileum

2019 ◽  
Vol 34 (1) ◽  
pp. 9-22
Author(s):  
Tesfaye Tolessa
Keyword(s):  
Smooth Muscle ◽  
Guinea Pig ◽  
High Performance ◽  
Longitudinal Muscle ◽  
Contractile Response ◽  
Inhibitory Effect ◽  
Muscle Strip ◽  
Organ Bath ◽  
Guinea Pig Ileum ◽  
Longitudinal Smooth Muscle

The skins of some amphibians contain potentially bioactive principles that may have pharmaceutical, medicinal, toxicological or chemical importance. In addition, such active principles can be used as tools in biomedical research. The present study aims at isolating and purifying bioactive principles from the skin of Bufo regularis and studying their effect on isolated longitudinal smooth muscle strip of guinea pig ileum. High performance liquid chromatography (HPLC) was used to isolate toad toxins. The effects of crude, semi-purified and purified extracts were tested on longitudinal smooth muscle of guinea pig ileum using organ bath method. Effect of the toxins was studied on electrically-induced contractile response and the basal tone of the longitudinal muscle strip. HPLC purification resulted in four different bioactive components with a λmax UV absorbance pattern of around 295 nm. When tested on guinea pig ileum they had persistent inhibitory effect on the electrically-induced contractile responses. The pattern of effect was initial excitatory followed by long lasting inhibitory effect on tone of longitudinal muscle. The HPLC eluate at 79th min in methanol preparative run corresponding to the eluate at 40th min in the acetonitrile run had the maximum bioactivity. Hence, it was concluded that the skin of B. regularis contains four different components which vary in their potency on isolated smooth muscle strip of guinea pig ileum.Keywords: Bufo regularis, organ bath, longitudinal muscle of ileum, toad toxin, electrical field stimulation

Chloride removal selectively inhibits phasic contractions of guinea pig ileal longitudinal smooth muscle

1982 ◽  
Vol 60 (12) ◽  
pp. 1741-1744 ◽  
Author(s):  
P. K. Rangachari ◽  
C. R. Triggle ◽  
E. E. Daniel
Keyword(s):  
Smooth Muscle ◽  
Guinea Pig ◽  
Longitudinal Muscle ◽  
Bathing Solution ◽  
Cholinergic Stimulation ◽  
High Potassium ◽  
Longitudinal Smooth Muscle ◽  
Anionic Composition ◽  
Chloride Removal

Removal of external chloride selectively and reversibly inhibits the phasic responses of the guinea pig ileal longitudinal muscle to high potassium and cholinergic stimulation. The binding of calcium to a relatively superficial pool is affected by chloride removal. Alterations in anionic composition of bathing solution affects the availability of calcium for excitation–contraction (E–C) coupling in smooth muscle.

The Morphology of the Gut of the Brown Trout (Salmo trutta)

1959 ◽  
Vol s3-100 (50) ◽  
pp. 183-198
Author(s):  
G. BURNSTOCK
Keyword(s):  
Smooth Muscle ◽  
Salmo Trutta ◽  
Longitudinal Muscle ◽  
Circular Muscle ◽  
Living System ◽  
Cardiac Stomach ◽  
Longitudinal Smooth Muscle ◽  
Brown Trout Salmo Trutta ◽  
Pyloric Stomach ◽  
Longitudinal Layer

1. In the trout gut a short oesophagus containing only striated circular muscles opens into a large cardiac stomach possessing inner circular and outer longitudinal smooth muscle-coats, as well as a musculsris mucosse. Ahout 45 pyloric caeca come off the intestine, which, while containing muscle-coats, does not possess a muscularis mucosae. In the rectum, the longitudinal muscle is as thick as the circular muscle-coat, hut in other regions the circular muscle is dominant, especially in the pyloric stomach where it is over 10 times as thick ss the longitudinal layer. 2. The mucosa is distinguished by the presence of a prominent layer of dense collagen, the stratum compactum, which is perforated only by nerves and blood-vessels. This layer forms a firm and relatively inextensible (approximately 10% extensibility) basis to the gut-wall. It limits the extensibility of the smooth muscle to 75% radially in the stomach and 25% radially and longitudinally in the intestine. In contrast, the stomachs of the pike and perch, which do not possess a stratum compactum, extend up so 200%. 3. A detailed description of the regional junctions and sphincters gives a basis for the interpretation of events occurring in the living system. Valves at the junction of the pneumatic duct with the oesophagus, and between the duodenum and pyloric stomach, serve to prevent the regurgitation of gas and semi-digested food respectively. A complex sphincter mechanism exists at the pylorus, and to a lesser extent at the antrum. A series of about five circular muscle-constrictors represents the anus. 4. It is suggested that the cells forming the stratum granulosum, a layer closely associated with the stratum compactum, are composed of active fibroblast cells producing collagen. 5. The rectum contains a muscular annulo-spiral septum of unknown function which protrudes into the lumen.

Muscarinic inhibition of ATP-sensitive K+ channels by protein kinase C in urinary bladder smooth muscle

1993 ◽  
Vol 265 (6) ◽  
pp. C1723-C1728 ◽  
Author(s):  
A. D. Bonev ◽  
M. T. Nelson
Keyword(s):  
Smooth Muscle ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Urinary Bladder ◽  
Guinea Pig ◽  
Smooth Muscle Cells ◽  
Katp Channels ◽  
Muscle Cells ◽  
Receptor Stimulation ◽  
Kinase C

We explored the possibility that muscarinic receptor stimulation can inhibit ATP-sensitive K+ (KATP) channels in smooth muscle cells from guinea pig urinary bladder. Whole cell K+ currents were measured in smooth muscle cells isolated from the detrusor muscle of the guinea pig bladder. Stimulation of muscarinic receptors by carbachol (CCh; 10 microM) inhibited KATP currents by 60.7%. Guanosine 5'-O-(2-thiodiphosphate) in the pipette (internal) solution prevented the CCh-induced inhibition of KATP currents. Activators of protein kinase C (PKC), a diacylglycerol analogue, and phorbol 12-myristate 13-acetate inhibited KATP currents by 63.5 and 73.9%, respectively. Blockers of PKC (bisindolylmaleimide GF-109203X and calphostin C) greatly reduced CCh inhibition of KATP currents. We propose that muscarinic receptor stimulation inhibits KATP channels in smooth muscle cells from urinary bladder through activation of PKC.

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