While a plant-based meal would qualify as vegan (adjective), a person who follows a plant-based (vegan) diet is not necessarily a vegan (noun). For example, someone could follow a plant-based diet but still wear leather and have no moral issue with hunting or killing animals for food.
Ball-and-stick model of cimetidine, the prototypical H 2 -receptor antagonist. The H2 receptor antagonists are a class of drugs used to block the action of histamine on parietal cells (specifically the histamine H2 receptors) in the stomach, decreasing the production of acid by these cells.he H 2 antagonists are competitive antagonists of histamine at the parietal cell H 2 receptor. They suppress the normal secretion of acid by parietal cells and the meal-stimulated secretion of acid.
Chloropyramine is known as a competitive reversible H1 receptor antagonist (also known as an H1 inverse agonist), meaning that it exerts its pharmacological action by competing with histamine for the H1 subtype histamine receptor.