Broncholytic activities

Despite the fact that the last mechanism may be basic for theophylline, a few xanthines, which in general lack the ability to bind with adenosine receptors, express the same, if not more broncholytic activity than theophylline. 

As drugs of mixed action, amphetamines activate adrenergic receptors and simultaneously release endogenic catecholamines (norepinephrine and dopamine) from neurons of the brain and periphery. Sympathomimetic effects on the periphery are very similar to those of ephedrine. Amphetamine elevates systolic and diastolic blood pressure and has weakly expressed, broncholytic action. These effects are more prolonged, yet less expressed, than with epinephrine. The distinctive feature of amphetamines is their psychostimulatory activity. Larger doses can cause hallucinations and mental conditions similar to paranoid schizophrenia. As a sympathomimetic, amphetamine is sometimes used for uterine inertia. Synonyms of amphetamine are phenamine and benzedrine. 

Theophylline and other methylxanthines also display a pharmacological effect on a number of other organ systems. Of course the most pronounced effect is relaxation of smooth musculature in the respiratory tract. However, theophylline is a CNS stimulant, and it lowers arterial blood pressure, increases diuresis, displays cardiotonic activity, and has a specific effect on the gastrointestinal tract. The effects listed are the most frequently encountered side effects upon taking theophylline as a broncholytic. 

The reactions of 6-acetamido-8-bromo-l,7-naphthyridine 334 with substituted piperazines in the presence of NaH afforded 6-acetamido-8-(4-J -piperazin-l-yl)-l,7-naphthyridines 335 possessing anti-inflammatory, antiarrhythmic, cardiotonic, vaso-dilatory, broncholytic, diuretic and antichlolinergic activities (1986USP4690924, 1988JAP62-30780, 1989JAP63-48277, 1990USP4866176). 

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