Interleukin-18 mRNA expression in the rat pituitary gland

The present study investigated the expression of IL-18 mRNA under several stimuli, and molecular structures of IL-18 mRNA of the rat pituitary. Real-time PCR demonstrated that IL-18 mRNA, highly expressed in anterior pituitary, significantly increased following stress and adrenalectomy. In situ hybridization combined with immunohistochemistry demonstrated that corticotrope cells expressed IL-18 mRNA. RACE and sequence analysis demonstrated that pituitary IL-18 mRNA possesses five newexons at the upstream of exon 1 and between exon 1 and exon 2, indicating the preferential usage of promoter 1. The present study Suggests that IL-18 in the corticotrope cells may play some roles in stress responses. (c) 2005 Elsevier B.V. All rights reserved.