흰쥐 혀침샘의 점액질에 미치는 N-Nitrosodimethylamine 독성에 대한 녹차의 완화 효과

Abstract

Biology Education Major, Division of Science Education, College of Education, Pusan National University, Busan 609-735, KoreaAbstractThis study was performed to determine alleviating effects of green tea (GT) on the N-nitrosodimethylamine (NDMA) toxicity to mucins in the rat lingual salivary glands. Sprague-Dawley rats were divided into five groups: untreated (Control), one week-NDMA administrated (NDMA), one week-GT administrated after NDMA for one week (NDMAGT), one week-NDMA administrated with GT (GTNDMA), and one-week NDMA administrated with GT after GT for one week (GTGTNDMA). The mucin properties were elucidated by periodic acid Schiff (PAS) reaction, alcian blue (AB) pH 2.5, AB pH 2.5-PAS, aldehyde fuchsin (AF) pH 1.7-AB pH 2.5, and high iron diamine (HID)-AB pH 2.5 staining. The lingual von Ebner's glands of NDMA group showed some changes such as contraction and destruction of the serous acini, decrease and disappearance of the cytoplasmic granules, vacuolation of cytoplasm, and the mucigenous duct cells. Also, in the lingual mucous glands, enlarged lumens, fused acini, disappearance of granules, vacuolation of cytoplasm, and mucigenous duct cells were observed. All the GT administrated groups had a tendency to recover. GTGTNDMA group recovered almost up to the state of the control group. The lingual von Ebner's glands of NDMA group showed a decrease of neutral mucin and the lingual mucous glands showed a decrease of both neutral and acidic mucins decreased in comparison with control group, although mucous acini secreting strong sulfomucin decreased while those secreting non-sulfomucin (sialomucin) increased. All the GT administrated groups had a tendency to recover. The degree of recovery in the GTNDMA group was stronger than in NDMAGT group and that of the GTGTNDMA group was almost up to the state of the control group. Plus, lingual von Ebner's glands of GTGTNDMA group contained much more neutral mucin than in the control group. In conclusion, it is suggested that NDMA exhibit the toxicity which affects on the mucin properties and which green tea alleviates.Key words: green tea, epigallocatechin gallate, N-nitrosodimethylamine (NDMA), salivary glands, mucin