Effects of carbamazepine on plasma extravasation and bronchoconstriction induced by substance P, capsaicin, acetaldehyde and histamine in guinea-pig lower airways

Bronchial asthma as neurogenic paroxysmal inflammatory disease: do some antiepileptic drugs have antiasthmatic properties?

Bronchial asthma is an inflammatory disease, and neurogenic inflammation may play important role in asthma mechanisms. But asthma also is an inflammatory disease with paroxysmal clinical picture. It is known that migraine and trigeminal neuralgia also are inflammatory diseases with paroxysmal clinical picture, and neurogenic inflammation plays important role in their mechanisms. Antiepileptic drugs are highly effective in pharmacotherapy of migraine and trigeminal neuralgia, and these drugs completely prevent attacks of migraine and trigeminal pain in great majority of cases. Due to this it is possible that some antiepileptic drugs may be highly effective in pharmacotherapy of asthma. Bronchial asthma can be considered as peripheral paroxysmal and inflammatory disease with definite central neurogenic mechanism. It is also possible that some antiepileptic drugs can suppress inflammatory processes in asthma through the central neural influence, like in therapy of migraine and trigeminal neuralgia.

Bronchial asthma as neurogenic paroxysmal inflammatory disease: a randomized trial with carbamazepine

PURPOSE

Based on the assumption that bronchial asthma has not only inflammatory, but also certain neurogenic paroxysmal mechanism and pathophysiological links with other non-epileptic paroxysmal inflammatory diseases--migraine and trigeminal neuralgia, we decided to investigate efficacy of antiepileptic drug carbamazepine in patients with moderate persistent or severe asthma.

METHODS

Sixty-three patients completed randomized double-blind, placebo-controlled trial.

RESULTS

Stable remission was achieved after carbamazepine treatment in 25 patients in active group (n=33). No significant improvement was registered in patients of placebo group (n=30). Following open-label treatment shows high and stable antiasthmatic efficacy of carbamazepine monotherapy.

CONCLUSIONS

Carbamazepine showed high efficacy in therapy of moderate persistent or severe bronchial asthma. Antiasthmatic activity of carbamazepine can be considered as influence on neurogenic mechanisms of asthma. We suppose that it is possible to use carbamazepine for therapy of bronchial asthma in clinical practice.

Ethanol causes inflammation in the airways by a neurogenic and TRPV1-dependent mechanism

Ethanol (EtOH) stimulates peptidergic primary sensory neurons via the activation of the transient receptor potential vanilloid-1 (TRPV1). EtOH is also known to trigger attacks of asthma in susceptible individuals. Our aim was to investigate whether EtOH produces airway inflammation via a TRPV1-dependent mechanism and to verify whether this effect is produced via a mechanism distinct from that of acetaldehyde (AcH). EtOH caused a Ca(2+)-dependent release of neuropeptides from guinea pigs airways, an effect that was inhibited by both capsaicin pretreatment and the TRPV1 antagonist capsazepine (CPZ). Furthermore, EtOH contracted isolated guinea pig bronchi, showing efficacy similar to that of carbachol: this effect of EtOH was sensitive to capsaicin pretreatment, tachykinin receptor blockade, and TRPV1 antagonism. The EtOH metabolite AcH also contracted isolated guinea pig bronchi, but this action was not affected by capsaicin pretreatment, tachykinin receptor, or TRPV1 antagonism. EtOH by intravenous or intragastric route of administration caused bronchoconstriction and increased plasma extravasation in the guinea pig airways, effects that were abolished selectively by CPZ. In conclusion, we have demonstrated that EtOH stimulates peptidergic primary sensory neurons in the guinea pig airways by TRPV1 activation. This excitatory effect of EtOH, distinct from that of AcH, results in neurogenic inflammatory responses that may contribute to the mechanism of EtOH-induced asthma.