The present study investigated the participation of D-serine and NR2 in antinociception produced by blockade of central erythropoietin-producing hepatocellular carcinoma (Eph) A4 (EphA4) signaling in rats with trigeminal neuropathic pain. Trigeminal neuropathic pain was modeled in male Sprague-Dawley rats using mal-positioned dental implants. The left mandibular second molar was extracted under anesthesia, and a miniature dental implant was placed to induce injury to the inferior alveolar nerve. Our current findings showed that nerve injury induced by malpositioned dental implants significantly produced mechanical allodynia; additionally, the inferior alveolar nerve injury increased the expression of D-serine and NR2 subunits in the ipsilateral medullary dorsal horn (trigeminal subnucleus caudalis). Intracisternal administration of EphA4-Fc, an EphA4 inhibitor, inhibited nerve injury-induced mechanical allodynia and upregulated the expression of D-serine and NR2 subunits. Moreover, intracisternal administration of D-amino acids oxidase, a D-serine inhibitor, inhibited trigeminal mechanical allodynia. These results show that D-serine and NR2 subunit pathways participate in central EphA4 signaling after an inferior alveolar nerve injury. Therefore, blockade of D-serine and NR2 subunit pathways in central EphA4 signaling provides a new therapeutic target for the treatment of trigeminal neuropathic pain.

The increases of industrial and technological development and human activities have disturbed the balance of natural nitrogen (N) circulation. These phenomena have induced that large amounts of N are to be present in excess in air, soil and water environment. We investigated the effects of excess of reactive nitrogen (Nr) compounds on soil and water environment ecosystems through literature and case studies, and suggested the strategy of mitigating the acidification in soil and water ecosystems. Nr moves to air, soil and water media, can be converted to different types, and interacts with other chemical compounds. As an efficient N management plan, the evaluation (application of monitoring and safety index) and the chemical restoration (research and development) of the acidification in soil and water environment ecosystems are required to minimize the effects of Nr as well as policies to regulate the various emission sources and amounts of Nr.

본 시험은 수도 멸구류의 난기생봉인 Anagrus nr. flaveolus의 월동후 반휴에 있어서 기생활동시기와 맥전에 있어서 기생율, 기주범위 그리고 본답에 있어서 기생활동등에 관하여 1977년부터 1979년까지 경남 진주에 위치한 본 시험국 시험포장을 중심으로 실시한 것으로서 그 결과를 요약하면 다음과 같다. 1. 반휴에 있어서 Anagrus nr., flaveolus의 월동후 기생활동은 4월상순에 가장 활발 하였으나 4월중 이후는 맥전으로 이동됨에 따라 현저히 감소되었다. 2. 맥전에 있어서 Anagrus nr. flaveolus의 애멸구 (Laodelphax striatellus F.)의 난에 대한 기생율은 애멸구 산란 최성기인 4월 중하순경에 였다. 3. 본답에 있어서 A. nr. flaveolus의 기생범위은 애멸구(Laodelphax striatellus F.), 흰등멸구(Segatella furcifera H.) 및 벼멸구(Nilaparvata lugens S.)였으며 그 중에서 애멸구난에 대한 기생율이 가장 높았다. 4. 본답에 있어서 기생활동은 7월상순과 8월하순9월상순 사이에 가장 활발하였으며 농약을 많이 살포하는 시기인 7월 8월은 살충제 무살포답이 살포답에 비하여 기생율이 현저히 높았으며 10월 이후부터 월동전까지는 반휴에서 기생활동이 활발하였다.