1 / 17

Effect of autonomic drugs on rabbit’s isolated intestine

Effect of autonomic drugs on rabbit’s isolated intestine. Dr Muhammad Raza. Action of autonomic drugs on the isolated Rabbit’s intestine. The smooth muscle of small intestine receives both parasympathetic and sysmpathetic innervation.

ganit
Download Presentation

Effect of autonomic drugs on rabbit’s isolated intestine

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Effect of autonomic drugs on rabbit’s isolated intestine Dr Muhammad Raza

  2. Action of autonomic drugs on the isolated Rabbit’s intestine • The smooth muscle of small intestine receives both parasympathetic and sysmpathetic innervation. • PARASYMPATHETIC preganglionic fibres relay in neurons located in the wall of the intestine in myenteric plexus and submucus plexus, and from there the post ganglionic fibres travel to the smooth muscle of intestine. • SYMPATHETIC preganglionic fibres relay in collateral ganglia OUT SIDE THE WALL OF INTESTINE. From these ganglia, postganglionic fibres arise and run with the blood vessels to supply the small intestine. • Parasympathetic nerves reach the intestine as preganglionic fibres and isolated intestine contains ONLY PARASYMPATHETIC GANGLIA. • PARASYMPATHETIC Stimulation  intestinal motility whereas sympathetic stimulation  it.

  3. TYPES OF RECEPTORS IN THE ISOLATED RABBIT’S INTESTINE • Nicotinic cholinoceptors (N) in parasympathetic ganglia • Muscarinic cholinoceptors (M) in smooth muscle • Adrenoceptors (, ) • Other receptors for histamine, serotonin, vasopressin

  4. INNERVATION AND RECEPTORS IN THE ISOLATED INTESTINE

  5. Classification

  6. APPARATUS FOR RECORDING CONTRACTIONS OF ISOLATED RABBIT’S INTESTINE

  7. Parts of apparatus (PowerLab)

  8. CONCEPTS • NIC (SD) stimulation of NN receptors of Parasympathetic ganglia located in the wall of intestine,  cause release of ACh from postganglionic parasympth nerve endings resulting in intestinal stimulation via muscarinic receptors. • NIC (LD) –Initial stimulation followed by block (DEPOLARIZING GANGLION BLOCK) of the Para-symp ganglia in the wall of the intestine.Chlorisondamine is a Competitive Ganglion blocker without stimulation. • NIC (SD) after NIC (LD) no response indicating BLOCKADE of Parasymp ganglia • ACh ---  Activation of muscarinic receptors • Atropine – Blocks muscarinic receptors by competing ệ ACh. • ACh after Atropine no change indicating complete blockade of Muscarinic receptors. • Adrenaline – Activation of Adrenoceptors (, ) ---  of intestinal tone and motility. • Propranolol – Blockade of  receptors • Phentolamine --  Blockade of  receptors • ADR after Phentolamine+Propranolol ---  No effects ---  Adrenoceptors (, ) are blocked

  9. Effect of unknown stimulant

  10. Effect of unknown stimulant

  11. Effect of unknown stimulant

  12. Effect of unknown stimulant

  13. Effect of unknown stimulant

  14. CONCEPTS • Adrenaline  Activation of Adrenoceptors (, )   of intestinal tone and  motility. • Propranolol  Blockade of  receptors • Phentolamine Blockade of  receptors • ADR after Phentolamine+Propranolol No effects  Adrenoceptors (, ) are blocked

More Related