Respiratory tract antitussive effects

Figure 8 shows the mechanism proposed for the antitussive effect of NTI [36]. When the respiratory tract is stimulated by irritants, e.g., xenobiotics, the cough reflex occurs, and the stress of coughing triggers the secretion of endogenous opioid peptides, which may simultaneously stimulate three types of opioid receptors. In a disease state, the stimulation of the 8 opioid receptor could block the p and k opioid receptor-mediated suppression of the cough reflex, which would result in continual coughing (Fig. 8a). When a selective 8 opioid antagonist, e.g., NTI, is administered,...

Narcotic Componnd that prodnces stnpor. Many opium derivatives are examples of strong narcotics. Narcotics can affect the central nervous system (CNS) and the gastrointestinal tract. The CNS effects include analgesia, euphoria, sedation, respiratory depression, and antitussive action. Chronic use of narcotics develops tolerance to the compounds and physical dependence. 

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