The Prophylactic and Therapeutic Effects of Cholinolytics on Perfluoroisobutylene InhalationInduced Acute Lung Injury: Tianhong ZHANG, et al. Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, P. R. ChinaPerfluoroisobutylene (PFIB) is a kind of fluoro-olefin that is ten times more toxic than phosgene. The mechanisms of the acute lung injury (ALI) induced by PFIB inhalation remain unclear. To find possible pharmacological interventions, mice and rats were exposed to PFIB, and the prophylactic or therapeutic effects of 3-quinuclidinyl benzilate (QNB) and anisodamine were studied and confirmed. It was observed that the wet lung/body weight and the dry lung/body weight ratios at 24 h after PFIB exposure (130 mg/m 3 for 5 min) were significantly decreased when a single dose of QNB (5 mg/kg) was administered intraperitoneally either 30 min before exposure or 10 h after exposure. Anisodamine was without any prophylactic or therapeutic effects at single doses below 30 mg/kg. The effects of QNB against PFIB inhalation induced ALI were well evidenced by the significantly decreased mice mortality at 72 h, the total protein concentration in bronchoalveolar lavage fluid at 24 h after the PFIB exposure, as well as the ultrastructural observations. The analysis of the time courses of lung sulfhydryl concentration, myeloperoxidase (MPO) activity and hemorheology assay showed that the toxicity of PFIB may be due to consumption of lung protein sulfhydryl, influx of polymorphonuclear leukocytes (PMNs) into the lung, and increased peripheral blood viscosity at a low shear rate, all of which were partially blocked by QNB intervention except for PMN influx. The results suggest that cholinolytics might have prophylactic and therapeutic roles in PFIB inhalation induced ALI. (J Occup Health 2005; 47: 277-285)

Suppression of Perfluoroisobutylene Induced Acute Lung Injury by Pretreatment withPyrrolidine Dithiocarbamate: Jian ZHAO, et al. Beijing Institute of Pharmacology and Toxicology, P.R. China-Perfluoroisobutylene (PFIB) is produced as a main by-product in large quantities by the fluoropolymer industry. As a highly toxic compound, even the case of brief inhalation of PFIB can result in acute lung injury (ALI), pulmonary edema and even death. To test for any preventive or therapeutic effects of pyrrolidine dithiocarbamate (PDTC), a NF-κB activation inhibitor, against PFIB inhalation-induced ALI, mice were exposed in a flow-past exposure system to PFIB and the prophylactic and therapeutic effects of PDTC were studied. The inhibitory effects of PDTC on ALI, the activation of NF-κB, as well as the expression of cytokines (IL-1β and IL-8) after PFIB exposure were evaluated. The results demonstrated that pretreatment with PDTC (120 mg/kg, 30 min before PFIB exposure) could significantly lower the lung coefficient (wet lung-to-body weight ratio, dry lung-tobody weight ratio, water content in the lung, and lung wet-to-dry weight ratio) and protein content in bronchoalveolar lavage fluid (BALF), but no effects of PDTC were found when PDTC was treated after PFIB inhalation, suggesting a preventative effect rather than a therapeutic effect of PDTC. Furthermore, the above preventative effects of PDTC (when given at 30 min before PFIB exposure) on PFIB-induced lung injury were achieved in a dose-dependent manner. In support of these preventive effects of PDTC, our toxicological studies demonstrated that PFIB-inhalation induced a quick activation of NF-κB (0.5 h post PFIB exposure) and expression of IL-1β and IL-8 (0.5 h and 1 h post PFIB exposure, respectively). Pretreatment with PDTC (120 mg/kg, 30 min before PFIB exposure) resulted in a significant inhibitive effect on the activation of NF-κB (0.5 h post PFIB exposure) and expression of IL-1β and IL-8 (1 h post PFIB exposure). The mortality, the extent of lung injury of the mice indexed by lung coefficients, the content of total protein and albumin in BALF, as well as the lung histopathologic changes, were dramatically alleviated in PFIB exposure after pretreatment with PDTC, clearly suggesting that PDTC has a prophylactic role against PFIB inhalation-induced ALI, and that NF-κB activation might play a central role in initiating an acute inflammatory response and in causing injury to the lungs after PFIB inhalation. (J Occup Health 2007; 49: 95-103)