Gut Motility Practical assessment Essay Example | Topics and Well Written Essays - 500 words

Gut Motility Practical assessment - Essay Example The stimuilation causes a reaction on the membrane. It becomes depolarized. Permeability to calcium ions is also increased. The calcium ions concentration in is increased as a result of the voltage gated calcium-ions channel. From the synaptic cleft ACh is released to fuse with the muscuranic receptors as a result. The Gs protein then activates PLC after phosphoinositides activation. Diacylglycerol and inositol-1,4,5-triphosphate are generated inducing phosphorylation and leading to the regulation of the calcium ion concentration, Burnstock (1972). This is the initialization of the ileum contraction. Diacylglycerol triggers protein kinase C, phosphorylating the target proteins leading to increased Ca+2 instigating contraction. 3. Explain the cellular mechanisms of action of morphine and atropine on field stimulated-induced contractions and how/why this is affected by naloxone, using the data collected from BOTH the field stimulated and the direct ACH-induced contraction of ileum As illustrated from the graphs, it is evident that morphine has no much variance with field stimulated contraction. Atropine however recorded a substantial effect on the ACh-induced contraction. Atropine at concentration levels of between 10-9 and 10−8 M antagonized the contractile response of the tissues causing relaxation of the ileum described by Brenda et.al (1983). Morphine, through Gi-protein, restrains the formation of cAMP (Gracious et.al, 2008). Ca+2 concentrations are increased. Endogenous ACh release is effected. However, for ACh-induced contractions, M3 receptors are exogenously occupied by ACh. This initiates the ileum contraction. This indicates that morphine has minimal effect on ACh action. It restricts about 0.35mm only. Naloxone does not exploit Muscarinic receptors. According to Gillan & Pollock (1980), it behaves like an opioid receptor antagonist. It has insignificant effect on ACh-induced contraction.