Muscarinic antagonist brain, involving both increased levels of acetylcholine and degeneration of dopaminergic pathways (nigrostriatal pathway). Thus, in parkinsonism there is decreased level of dopaminergic activity. One method of balancing the neurotransmitters is through blocking central cholinergic activity using muscarinic receptor antagonists. Atropine acts on the M2 receptors of the heart and antagonizes the activity of acetylcholine. It causes tachycardia by blocking vagal effects on the sinoatrial node. Acetylcholine hyperpolarizes the sinoatrial node, which is overcome by MRA and thus increases the heart rate. If atropine is given by intramuscular or subcutaneous injection, it causes initial bradycardia. This is because by i.m/s.c
Blank node Blank node In RDF, a blank node (also called "bnode") is a node in an RDF graph representing a resource for which a URI or literal is not given. The resource represented by a blank node is also called an anonymous resource. According to the RDF standard a blank node can only be used as subject or object of an RDF triple. Blank nodes can be denoted through blank node identifiers in the following formats, RDF/XML, RDFa, Turtle, N3, N-Triples, and RDFa. The following example shows how it works in RDF/XML. The blank node identifiers are only limited in scope