Physiological antagonism is found in ?

Ans. is 'd' i.e., Adrenaline and histamine Physiological antagonists o Physiological antagonists are those that produce opposite action by acting on different receptors. Example 1.Histamine causes bronchoconstriction H1 receptors and this action is antagonized by adrenaline which causes bronchodilodation through 132 receptors (option d) 2.Leukotrienes cause bronchoconstriction cystinyl leukotriene receptors and this action is antagonised by salhutamol which causes bronchodilatation through 132 receptors (option e) Receptor antagonists (Pharmalogical antagonists) Receptor antagonists are those drugs that blocks the action of agonist by acting on same receptors. Example 1. Isoprenaline is 131 and p, receptor agonist while propranolol has antagonistic action on 13, and 02 receptors (option 'c') about option a and b o Adrenaline (a, + + R + + weak (33 agonist), isoprenaline (0, + 02 + 13, agonist) and salbutamol (13., agonist) --> all three are sympathomimetic drugs (not antagonists)