Bronchodilators, /3-stimulants

O) Other than psychedelic activity other than psychedelic activity has been demonstrated. These "other" activities include such things as anti-depressant, analgesic, anorexic, adrenergic bronchodilator, stimulant and antitussive. 

Adrenergic, CNS stimulant Expectorant, bronchodilator Stimulant, hepatoprotective Vermicide, taenifuge... 

Many alkaloids have pronounced biological properties, and a substantial number of the pharmaceutical agents used today are derived from naturally occurring amines. As a few examples, morphine, an analgesic agent, is obtained from the opium poppy Papaver somnifemm. Cocaine, both an anesthetic and a central nervous system stimulant, is obtained front the coca bush Erythroxylon coca, endemic to upland rain forest areas of Colombia, Ecuador, Peru, Bolivia, and western Brazil. Reserpine, a tranquilizer and antihypertensive, comes from powdered roots of the semitropical plant Rauwolfia serpentina. Ephedrine, a bronchodilator and decongestant, is obtained front the Chinese plant Ephedra sinica. 

Examples of the xanthine derivatives (drag that stimulate the central nervous system [CNS] resulting in bronchodilation, also called methylxanthines) are theophylline and aminophylline. Additional information concerning the xanthine derivatives is found in the Summary Drag Table Bronchodilators. 

P2-Agonists cause airway smooth muscle relaxation by stimulating adenyl cyclase to increase the formation of cyclic adenosine monophosphate (cAMP). Other non-bronchodilator effects have been observed, such as improvement in mucociliary transport, but their significance is uncertain.11 P2-Agonists are available in inhalation, oral, and parenteral dosage forms the inhalation route is preferred because of fewer adverse effects. 

Beta receptors are also unevenly distributed with P2-receptors the more common subtype on the effector tissues. Beta-two receptors tend to be inhibitory for example, P2-receptor stimulation causes relaxation of vascular smooth muscle and airway smooth muscle, resulting in vasodilation and bronchodilation, respectively. Beta-two receptors have a significantly greater affinity for epinephrine than for norepinephrine. Furthermore, terminations of sympathetic pathways are not found near these receptors, so P2-receptors are stimulated only indirectly by circulating epinephrine instead of by direct sympathetic nervous activity. 

Another noteworthy example of the relaxation of smooth muscle by way of P2-receptor stimulation involves airways. Bronchodilation, or opening of the airways, facilitates airflow in the lungs. Any direct sympathetic innervation to the lungs is irrelevant in this respect because only circulating... 

Selective sympathomimetics cause relaxation of bronchial smooth muscle and bronchodilation by stimulating the enzyme adenyl cyclase to increase the formation of cyclic adenosine monophosphate. They may also improve mucociliary clearance. 

Theophylline and aminophylline may produce bronchodilation by inhibition of phosphodiesterase (thereby increasing cyclic adenosine monophosphate levels), inhibition of calcium ion influx into smooth muscle, prostaglandin antagonism, stimulation of endogenous catecholamines, adenosine receptor antagonism, and inhibition of release of mediators from mast cells and leukocytes. 

Dichloro-isoprenaline was the first [3-adrenoceptor antagonist to he described (6). It was discovered in a search for specific (3-stimulants as bronchodilators. This compound is a partial agonist, i.e. it can antagonise the action of isoprenaline hut itself is a (3-stimulant. (The stimulant action of dichloro-isoprenaline is readily demonstrated in an animal depleted of natural catecholamines ( with say reserpine). In this type of preparation it will stimulate say heart rate to a maximum of 70% of that produced hy isoprenaline itself). 

Similarly, where a stimulation action (e.g., antipyretic effect of NSAIDS through thermolysis or production of cAMP by bronchodilator beta-2 agonisU ) is involved, the stimulation response... 

Clinically, it has been confirmed that the drug is an effective bronchodilator with very little cardiovascular activity it does not appear to increase hypoxaemia [439]. A more detailed study [440], comparing salbutamol with isoprenaline and orciprenaline, demonstrated that 200 jug of salbutamol provided effective bronchodilation for at least three hours without detectable cardiac stimulation. Equivalent bronchodilator doses of isoprenaline and orciprenaline were 1000 /ag and 1500 jUg respectively. The bronchial effects of isoprenaline, though initially intense, waned within one hour and cardiac effects were noted. In this trial little objective difference could be detected between salbutamol and orciprenaline at the dose levels used, though most patients expressed preference for salbutamol. 

Carboxymethylthio derivatives of 1,3-dialkyl-6-aminouracils (LXIX) and their amides possess anti-inflammatory activity, as evidenced by their ability to inhibit local edema formation [434,435]. Bronchodilator and CNS stimulant activity are also claimed. The related 1-aryl derivatives (LXIX R = Ar) are reported to have anti-inflammatory, hypocholesterolemic, pepsin-inhibiting, and anti-ulcer properties [436]. 

Albuterol is a bronchodilator used in inhalation aerosols for the treatment of asthma. It is a P2-adrenergic drug. The bronchial muscles are controlled by P2 receptors. Stimulation of the P2 receptors leads to the relaxation of the bronchial muscles and the opening of the airways. But it must not encourage a stimulation, leading to vasoconstriction, or Pi stimulation, giving an... 

Elderly patients and those sensitive to -adrenergic stimulants Start with 2 mg 3 or 4 times/day. If adequate bronchodilation is not obtained, increase dosage gradually to as much as 8 mg 3 or 4 times/day. 

Pharmacology Amphetamines are sympathomimetic amines with CNS stimulant activity. CNS effects are mediated by release of norepinephrine from central noradrenergic neurons. Peripheral activities include elevation of systolic and diastolic blood pressures and weak bronchodilator and respiratory stimulant action. Pharmacokinetics ... 

This xanthine derivative is an only a modest bron-chodilator in COPD, and because of its narrow therapeutic range, frequently seen adverse effect and drug interactions, it is becoming less frequently used, some patients experience side effects even within the therapeutic range. The non-bronchodilator effects of theophylline such as systemic and pulmonary vascular dilatation, central nervous system stimulation, improvement of the strength and effectiveness of respiratory muscles and possibly anti-inflammatory effects are of disputed clinical significance at usual therapeutic levels. 

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