The Effect of Neuropeptide Y on Mucociliary Activity in the Rabbit Maxillary Sinus

Abstract

The effect of neuropeptide Y (NPY) on mucociliary activity in the rabbit maxillary sinus was investigated in vivo by injecting NPY at increasing dosages into the maxillary artery, response being recorded photoelectrically. at dosages of 0.1-5.0 μg/kg, NPY reduced mucociliary activity dose-dependently. the maximum decrease being 14.6 ± 1.8%, at a dosage of 5.0 μg/kg. the NPY-induced reduction of the mucociliary activity manifested brief latency, the peak effect occurring within 3 min followed by a slow return to the baseline value 4-9 min after injection. the response of mucociliary activity to NPY remained unaffected by pretreatment with the a-adrenergic antagonists yohimbine (a₂) at 100.0 μg/kg and phentolamine (a₁ + a₂) at 0.2-1.0 mg/kg. indicating that the effect of NPY is not mediated via o-receptors. Pretreatment with the calcium antagonist nifedipine at 100.0 μg/kg inhibited the effect of NPY, suggesting that the NPY-induced decrease may be calcium dependent.

Key Words:

• maxillary sinus
• rabbit
• mucociliary activity
• neuropeptide Y
• nifedipine
• yohimbine and phentolamine