Abstract: 【Objective】This experiment was conducted to detect the existence of IFNGR in the celiac superior mesenteric ganglion (CCMG) in goats.【Method】The CCMG were taken from male and female goats, respectively. The CCMG were fixed with 40 g·L^-1 paraformaldehyde in phosphate buffer for 4 hours. Fixation was followed by thorough rinsing in water for 10 h, then dehydrated in graded alcohols, embedded in paraffin and cut into thick sections to prepare for immunohistochemical and H.E. staining. The sections were divided into 4 groups. The first group stained with H.E. staining. The second group was deparaffinized with xylene and ethanol, and processed for immunohistochemical SP staining. The third group was stained with immunohistochemical SP staining and hematoxylin counterstain. The last group was used as the negative control group. After staining, the specimens were examined and photographed with Motic microscope with digital camera. The digital images were analytically processed and got the relative expression of IFNGR with image-analysis software. All data were processed by SPSS18.0 software, mono factor analysis of variance was used for Significance test. After CCMG thoroughly grinded, the total RNA was extracted with extract RNA kit, and primers were designed according to IFNGR1 cDNA sequence of bovine. Then, the IFNGR1 cDNA of goat was cloned and amplified by PCR. The amplification was detected whether there was the target band by agarose gel electrophoresis and DNA sequencing. The sequencing results were compared and affirmed in the NCBI, and compared with sequences of other species. 【Result】The results of immumohistochemical staining showed that: IFNGR immunopositivity was widely distributed in CCMG of goat, and different levels of staining existed in neurons, satellite cells and nerve fibers. All the neurons were IFNGR positive. Almost every cytoplasm of neurons were dyed tan, were IFNGR positive, only a few cytoplasmic stained weak were weakly positive. In the nucleus of neurons, the karyoplasms were strongly positive, and the nucleolus were weakly positive or negative. In the non-neuronal structure, the satellite cells and nerve fibers were moderately or weakly positive. The relative expression of IFNGR in neuron was very significantly higher than that in non-neuronal structure (P＜0.01). The PCR detection results showed that there was a clear white target band at 300-400 bp in the line of PCR production. The DNA sequenced analysis showed that the full length of IFNGR1 gene amplified by PCR was 376 bp. Homologous comparison with other species indicated that IFNGR1 gene of goat homology with sheep (98%, XM_004011371.1) was the highest, followed by cattle (97%, NM_001035063.1), Sus scrofa (84%, NM_001177907.1), Oryctolagus cuniculus (73%, XR_085137.1) and Rattus norvegicus (66%, NM_053783.1), in the NCBI.【Conclusion】The results suggested that the IFNGR in the CCMG of goats mainly expressed and located in sympathetic postganglionic neurons which were provided with the conditions for the role of IFN-γ, which implied that the CCMG may act as critical point to coordinate the immune regulation of IFN-γ with neuroregulation of autonomic nerve on gastrointestinal tract.

Key words: interferon-&gamma, receptors, celiac superior mesenteric ganglion, immunohistochemical SP method, PCR, goat