Effects of β-Adrenergic Amines on Frog Gastric Mucosa

Summary

Beta adrenergic amines like alpha adrenergic amines decreased the H⁺ secretory rate and increased the transmucosal resistance of the gastric mucosa of Rana pipiens. A concentration of 0.1 mM propranolol in the nutrient solution followed by a combination of 0.1 mM propranolol and either 0.25 mM isoproterenol or 1.0 mM epinephrine reduced the effects of the beta agonists, isoproterenol and epinephrine. However, a concentration of 0.25 mM isoproterenol or 1.0 mM epinephrine followed by the same combination did not reduce the effects of isoproterenol or epinephrine alone. These results suggested the existence of beta receptor sites in addition to non-specific sites.