Cold Exposure Enhances Nitroxidergic Nerve-Mediated Vasodilatation in Canine Nasal Mucosa

The Japanese Journal of Pharmacology

Koji Yajin²  Hiroko Kawamoto²  Masashi Sasa¹  Hiroshi Watanabe²  Hiromichi Tsuru¹ 

[1] Department of Pharmacology, Hiroshima University School of Medicine;Department of Otorhinolaryngology, Hiroshima University School of Medicine

关键词: Nasal mucosa (dog);    Cold exposure;    Nitric oxide;    Nitroxidergic nerve;    Vasodilatation;   

DOI  :  10.1254/jjp.77.287

学科分类：药理学

来源: Nihon Yakuri Gakkai Henshuubu / Japanese Pharmacological Society

【 摘 要 】

References(19)Cited-By(8)We have previously reported that there is non-adrenergic, non-cholinergic (NANC) innervation in canine nasal mucosa and that the relaxation response to electrical stimulation of the NANC nerve is mainly mediated by nitric oxide (NO). In the present study, we examined the effect of cold exposure (24°C) on nitroxidergic nerve-mediated vasodilatation in isolated canine nasal mucosa. Nasal mucosa strips, prepared from canine nasal septum and moderately precontracted with methoxamine in the presence of atropine and guanethidine, relaxed in response to transmural electrical stimulation (square pulses of 0.5-msec duration, at 5 Hz and 25 V). The degree of relaxation at 24°C (55.4±13.2% of methoxamine-induced contraction, mean±S.D., n=6) was significantly greater than that at 34°C (33.8±8.6%, n=6). This phenomenon was reversible. In contrast, the magnitude of relaxation responses to an NO donor (sodium nitroprusside of 0.1 and 1 μM) remained unchanged by cold exposure. These results suggest that the release of NO from the nitroxidergic nerve endings is augmented by cold exposure and, thus, vasodilatation of the nasal blood vessel is enhanced, thereby contributing to the swelling of the nasal mucosa in cold conditions.

【 授权许可】

Unknown