Tabassian A R, Snider R H, Nylen E S, Cassidy M, Becker K L
Department of Medicine, George Washington University School of Medical Sciences, Washington, D.C.
Anat Rec. 1993 May;236(1):253-6. doi: 10.1002/ar.1092360131.
Various acute stimuli, including cigarette smoke, induce hypercalcitonemia in man and hamsters. We have shown that this occurs also in thyroidectomized subjects. In the present study we have further explored this phenomenon of secretion from the lungs by studying, simultaneously, the HPLC characteristics of pulmonary tissue and serum in control hamsters and in animals immediately following short-term exposure to cigarette smoke. In addition, we have studied the immunoheterogeneity of lung calcitonin 24 hours following the acute exposure. Control lungs contained monomeric immunoreactive calcitonin (M-iCT), high molecular mass iCT (H-iCT), and CT fragments. Immediately following smoke exposure, there was an acute decrease of lung iCT by radioimmunoassay (RIA) which consisted primarily of a decrease in M-iCT by HPLC. Simultaneously, the iCT increase in the serum by RIA was shown by HPLC to involve M-iCT. Twenty-four hours after smoke inhalation, the lung iCT by RIA and M-iCT by HPLC had returned towards control levels. These findings document the molecular characteristics of lung iCT following acute cigarette smoke stimulation, and suggest that under certain circumstances M-iCT may be actively secreted by the lung. It remains to be determined whether this type of secretion reflects hemocrine or paracrine release and what the physiological role for such a secretion may be.
包括香烟烟雾在内的各种急性刺激可导致人和仓鼠出现高降钙素血症。我们已经表明，这种情况在甲状腺切除的受试者中也会发生。在本研究中，我们通过同时研究对照仓鼠以及短期接触香烟烟雾后的动物的肺组织和血清的高效液相色谱（HPLC）特征，进一步探讨了肺分泌的这一现象。此外，我们研究了急性暴露24小时后肺降钙素的免疫异质性。对照肺含有单体免疫反应性降钙素（M-iCT）、高分子量iCT（H-iCT）和CT片段。烟雾暴露后立即通过放射免疫测定（RIA）发现肺iCT急性减少，这主要是通过HPLC检测到M-iCT减少。同时，通过HPLC显示RIA检测到血清中iCT增加涉及M-iCT。吸入烟雾24小时后，RIA检测的肺iCT和HPLC检测的M-iCT已恢复至对照水平。这些发现记录了急性香烟烟雾刺激后肺iCT的分子特征，并表明在某些情况下，M-iCT可能由肺主动分泌。这种分泌类型是否反映血液分泌或旁分泌释放以及这种分泌的生理作用可能是什么，仍有待确定。
