ABSTRACT
Objective To investigate the ultrastructure and function changes of the thyroid parafollicular cell in ANP rats and to study the possible mechanism of hypocalcemia during ANP.Methods Thirty-two male Wistar rats were randomly divided into 4 groups:sham operation group ( SO group) and ANP 3,6,12 h groups.ANP model was induced by retrograde injection of 5％ sodium taurocholate into the biliopancreatic duct. The serum levels of amylase,lipoidase,calcitonin and Ca2+ were measured.The pathological changes in pancreatic tissue were observed.The ultrastructure changes of thyroid parafollicular cell were observed.ResultsThe serum levels of amylase,lipoidase,calcitonin and Ca2+ were (4025 ±579)U/L,(8272 ± 794) U/L,(383.6 ± 64.5) pg/ml,(2.41 ± 0.12) mmol/L at 6h in ANP group,which were significantly higher than those in SO group [ ( 1063 ± 129 ) U/L,( 55 ± 18 ) U/L,( 143.1 ± 42.2 ) pg/ml,(2.97 ±0.12 ) mmol/L ( P ＜0.05 ) ].Under the electron-microscopy,the nucleus of thyroid parafollicular cells shrinked and mitochondrial proliferation and endoplasmic reticulum fusion appeared.After 6 h,all the organelle reduced and disappeared,and only small amount of secretory granules remained.Conclusions Changes in the structure and function of the thyroid parafollicular cells occur in rats of ANP,and they induce the development of hypocalcemia.