The effect of morphine and naloxone on the guineapig isolated ileum. Analysis of the effects of a range of drug molecules on. Take a guinea pig, stun it to cause death, immediately open the abdominal cavity with surgical scissors and clip off 10 cm of ileum, starting at or near the ileocecal junction. Ribeirao preto, so paulo, brazil received 18 december 1975 abstractclarks equation used in its inverted form double reciprocal plots was. Pharmacological examination of contractile responses of.
M, and then superfused with tyrode solution containing hemicholinium3 10. Simulates an isolated preparation of the guinea pig ileum, a. A well accepted problem of performing organbath tissue based pharmacology teaching in the. Reflex contractions of the longitudinal muscle coat of the isolated guinea pig ileum. Guinea pigs teeth are constantly growing, so they need to eat things that will constantly graze and grind. Metronidazole and 5aminosalicylic acid enhance the. All articles from sheffield bioscience programs, dr. Random elements are incorporated in ileum to simulate the inherent biological variability in the response to the same dose of agonist.
These contractions can be reduced by the application of adenosine and related compounds. Pharmacological examination of contractile responses of the. The isolated ileum simulation university of maryland. A small portion of guinea pig ileum was isolated on a wire tissue holder and mounted in an organ bath with the free end and attached to a force transducer. These efsinduced contractions were abolished by tetrodotoxin 3 107 mol l1 or atropine 106 mol l 1, thus indicating that these contractions were because of release of acetylcholine from enteric nerves. The concentration response curve of acetylcholine in chicken ileum. Novel pharmacological profile of muscarinic receptors mediating.
However, formatting rules can vary widely between applications and fields of interest or study. Clonidine and dexmedetomidine potently inhibit peristalsis in. Histamine receptors in the guinea pig ileum springerlink. The latest installer that can be downloaded is 679 kb in size. The role of histamine h1, h2 and h3receptors was studied on neural transmission in ascending excitatory pathways of the guinea pig ileum. Oxom contracted the ileum with an ec50 value of 35 nm and a hill coefficient of 1. Reflex contractions of the longitudinal muscle coat of the isolated guineapig ileum 1959 the journal of physiology. We previously proposed a novel sensory circuit in the ens which consists of multifunctional rapidly adapting mechanosensitive enteric neurons ramen in the guinea pig. Dissection of the guinea pig ileum was carried out by lab assistant, the procedures were stated on pharmacology lab manual pha 3801 unit manual pg 42.
You can manage this and all other alerts in my account. Jun 15, 2014 contractions of isolated guinea pig ileum. Jan 29, 2009 the effect of naloxone on fresh and overnight preparations of the guinea. This program simulates an isolated preparation of the guinea pig ileum, a smooth muscle preparation exhibiting little spontaneous contractile activity, which is extensively used for pharmacological studies. In this series of exercises, you will use the ileum computer simulation program to obtain additional data and determine the sites of action of an unknown agonist or antagonist. Ileum accurately simulates laboratory experiments which investigate the effects of drugs on the in vitro guineapig ileum. H1 and h2receptors for histamine in the ileum of the guinea pig. Histaminergic effect of crude papaya latex on isolated. Once payment has been received the software is supplied as a download. This means they have a large cecum allowing them to consume moderate levels of roughage. In fish, the divisions of the small intestine are not as clear and the terms posterior intestine or distal intestine may be used instead of ileum. Clonidine and dexmedetomidine potently inhibit peristalsis. The user is introduced to doseresponse curves through simulated experiments of the action of drugs on isolated guinea pig ileum.
Guinea pig ileum a computer simulation program to teach the effects of drugs and electrical stimulation on the enteric nervous system, using an isolated preparation of the guinea pig ileum. Ileum accurately simulates laboratory experiments which investigate the effects of drugs on the in vitro guinea pig ileum. Effects of drugs on isolated ileum motility in guinea pig. Clonidine and dexmedetomidine potently inhibit peristalsis in the guinea pig ileum in vitro you will receive an email whenever this article is corrected, updated, or cited in the literature.
We initially investigated mec response directly applied in guineapig ileum. Cal pharmacology software for undergraduate medical students. Its main function is to absorb vitamin b 12, bile salts, and whatever products of digestion that were not. Wash out the contents inside the intestine with tyrodes solution aerated with 95% oxygen and 5% carbon dioxide. This program simulates an isolated preparation of the guinea pig ileum. Development of an ex vivo model for pharmacological.
A computer simulation program to teach the effects of drugs and electrical stimulation on the enteric nervous system. Pharmacological examination of contractile responses of the guinea. Pharmacology experimental benefits from the use of. The effects of atropine on 3hacetylcholine secretion from. The guinea pig ileum simulation programme simulates the effects of drugs and electrical.
Simulations of pharmacological experiments on the guinea pig. The role of histamine h1, h2 and h3 receptors on enteric. Guinea pigs have a cecal fermenters digestive system. Figure 1 provides a summary of the software which is either currently available or will become available from pccal in the 19941995 session background preliminary studies indicate that the introduction of multi. Simulations of pharmacological experiments on the guinea pig ileum covers basic receptor theory, including occupancy and how response size is related to occupancy. Histaminergic effect of crude papaya latex on isolated guinea. Innovative software solutions and expert services for. Afdx 116 blocked contractions of guinea pig ileum elicited by the nonselective agonist oxom. Isolated guineapig ileum simulator ileum screenshot. Practical report 1 drug interaction pha3801 monash.
On an ending note, ileum provides you with a straightforward means of mimicking the biological variability in relation to various drugs and the response they trigger on in. The normal responses of strips of ileum from the guinea pig to histamine, acetylcholine, electrical stimulation, and to added antigen horse serum were determined. These programs use data previously obtained from actual in vivo experiments to. The aim of this study was to validate this concept by studying its applicability to. Download ileum carry out virtual experiments on guinea pig ileum with the help of this educational tool that allows you to test out the effects of various drugs. To determine unknown concentration of histamine by using guinea pig ileum guinea pig ileum is most sensitive to histamine. The guinea pig ileum lacks the direct, highpotency, m2muscarinic. The experiment involves a 2cm piece of ileum in tyrodes solution. Histamine h1 and ha vasodilator mechanisms in the guinea pig. Guinea pig ileum simulation an online training package from. Background within the gut the autonomous enteric nervous system ens is able to sense mechanical stimuli and to trigger gut reflex behaviour. Responses to acetylcholine and histamine were recorded alone, then in the presence of drug a and drug b. Bioassay of histamine the usually accepted mothods for. Code 1952 has reported that the most con venient tissue for the bioassay of histamine is guinea pigs terminal portion ofthe ileum.
Educational simulation models in the biomedical sciences ilar. Guinea pig digestive system by gabrielle samuels on prezi. The slope of the curves obtained for acetylcholine on the ileum of the rabbit, rat and mouse, is the same as that obtained on the ileum of the guinea pig. Pieces 4 to 6 cm long were cut from the guineapig ileum about 5 cm above the ileocaecal valve. Histamine and some related compounds acting selectively on h2or h1receptors were tested for their ability to contract the guinea pig ileum, in the usual whole ileum preparation and in the longitudinal muscle preparation. Mechanosensitive enteric neurons in the myenteric plexus. The longitudinal smooth muscle of the guineapig ileum small intestine contracts in response to acetylcholine. A computer simulation program to teach the effects of drugs and electrical stimulation. Muscarinic agonists elicit contraction in the standard guinea pig ileum bioassay through activation of m 3 muscarinic receptors that are also linked to phosphoinositide hydrolysis. This software is an intellectual property of biosoft. It has the spontaneous activity and specificity is improved by using atropine for histamine assay.
The software simulates an experimental setup on an isolated piece about 2 cm of guinea pig ileum removed from a freshly killed guinea pig and suspended in warmed and aerated physiological solution called tyrodes solution. Experimental animals like rat, guinea pig, rabbit, etc. Simulates an isolated preparation of the guinea pig ileum. Submucosal prepara tions were dissected from the guinea pig ileum as previously described in detail. The isolated ileum simulation the isolated ileum represents a valuable tool for evaluating the actions of pharmacological agents that affect the autonomic nervous system.
I need to prepare for and then write up an experiment about guinea pig ileum contractions using an organ bath. It is possible to mimic experiments to identify an unknown compound. Rocha e silva department of pharmacology, faculty of medicine, u. By working through the package, the user should be able to design an experiment to find out the pharmacological properties of an unknown drug on the guinea pig ileum ie to find out whether the drug is an agonist fullpartial or an antagonist, and its possible sites of action including receptors. The myenteric plexuslongitudinal muscle preparation of the guineapig ileum was incubated with 3 hcholine 112515. In all cases, cocaine, nicotine and epinephrine, slow the contraction rate of the ileum. The concentration response curve of acetylcholine in chicken ileum shifted toward.
On an ending note, ileum provides you with a straightforward means of mimicking the biological variability in relation to various drugs and the response they trigger on invitro guinea pig ileum species. Prepare a piece of guinea pig ileum for transmural stimulation. The longitudinal smooth muscle of the guinea pig ileum small intestine contracts in response to acetylcholine. In the guinea pig their action is more marked when histamin is used than when acetylcholine is used. Simulation of experiments on the isolated guinea pig ileum. Responses of a section of guinea pig ileum to single ec 50 concentrations of histamine and acetylcholine. Free ileum software, best ileum download page 1 at. Screen display from the guinea pig ileum program 1. The program lets you be in full control of the test results, which you can analyze by looking at a graph you may export, so it could prove a. Simulations of parmacological experiments on guinea pif ileum pccal. A twocompartment oral and anal compartments bath was used. The guineapig ileum is innervated by the enteric, sympathetic and parasympathetic divisions of the autonomic nervous system. The concentrations elicited by histamine in both kinds of preparations were not potentiated by cimetidine or metiamide and were not inhibited by administration of h2. Surprisingly, the most abundant muscarinic receptor in the ileum is the m 2 which causes a specific inhibition of cyclic amp accumulation elicited by the.
Printed in great britain h1 and h2receptors for histamine in the ileum of the guinea pig ivone bareicha and m. Functional role of m2 muscarinic receptors in the guinea pig. Analysis of the effects of a range of drug molecules on evoked contractions of the guinea pig ileum. The effect of naloxone on fresh and overnight preparations of the guineapig ileum. Bioassay using guinea pig ileumbioassay using guinea pig ileum bioassay of histamine on isolated guinea pig ileum can be determined by matching bioassay interpolation bioassay bracketing assay multiple point assays 14. Histamine h1 and ha vasodilator mechanisms in the guinea. Ileum, guinea pig, muscarinic receptor knockout mice. Effect of the test substances on isolated guinea pig ileum in tyrode solution guinea pigs were sacrificed by co. Functional role of m2 muscarinic receptors in the guinea. A perfusion of the tissue was then initiated with a lockes solution lacking one of three ions. Can anyone recommend any good textbooks that outline this procedure. Responses of a section of guineapig ileum to single ec 50 concentrations of histamine and acetylcholine.
518 1138 1420 690 91 1357 421 1210 957 1096 1310 206 1199 1586 650 131 214 293 384 272 656 307 1491 285 917 1176 1325 639 469 73 1351 1273