Expression Of Nuclear Factor-kappa B, Intercellular Adhesion Molecules-1 In Dura Mater Of Glyceryl Trinitrate Infusion Rat And The Role Of 94-95-10Y

ObjectiveMigraine is a common and episodic neurological disorder. In recent years, there has been a tremendous progress in the pathophysiological mechanisms and biochemical pathways of migraine. Neurogenic inflammation within dura mater has been proposed as fundamental to the pathogenesis of migraine. Sensitization and activation of the trigeminal ganglia nerves that innervate the meningeal blood vessels and release of neuropeptide calcitonin gene-related peptide (CGRP) is believed to play an important role in neurogenic inflammation within dura mater.Along with the development of modern molecular biology, expression and regulation of gene in migraine were focused on nuclear factor-kappa B ( NF-κB ) and inhibitory-kappa B ( I-κB ). NF-kB belongs to a rel/ NF-κB family and is primarily found in immune, inflammation and cellar defenses, which plays a critical role in regulating expressions of multiple genes. Intercellular adhesion molecules-1 (ICAM-1 ) is an inducible intercellular adhesion protein, which mediates the adhesion between leucocytes and vascular cells. It exerts important roles in the inflammatory response. ICAM-1, low expression levels in the static condition, is regulated by multiple transcription factors. NF-κB activities in early time course and IL-1β, TNF-α, iNOS expressions in a delayed time course increases in dura maters of rats after glyceryl trinitrate (CTN) infusion. However, NF-κB, ICAM-1 expressions and gene regulations of ICAM-1 are unknown in dura maters of rats after CTN infusion.Compound 94-95-10Y is a new anti-migraine alkaloid abstracted from the plant drugs by our laboratory. Our previous studies had proved that 94-95-10Y inhibited the releases of CQRP and plasma protein extravasations in dura maters of rats with migraine, which reflect the inflammatory response of dura maters. However, the further mechanisms in the inflammatory response are unclear. Inthe present study, we established the rat migraine model of GTN infusion. Using the immunohistochemistry and Western-blot, we examined the characteristics of NF-kB and ICAM-1 protein expressions in dura maters of rats after GTN infusion. The histochemistry examined the inflammatory response in dura maters of rats after GTN infusion. Meanwhile, we examined the roles of 94-95-10Y on NF-kB and ICAM-1 expressions and the inflammatory response in dura maters of rats after GTN infusion.MethodsRat migraine model was established with GTN 2μg. · kg^-1 · min^-1 infusion for 30min. The immunohistochemistry was used to observe NF-kB expressions in cell nuclei of dura maters of rats 0.5, 1.0, 1. 5, 2. 0, 4. Oh after GTN infusion or 2. Oh after normal saline infusion. The levels of NF-kB protein expressions in cell nucleus of dura maters of rats at the same time points were detected by Western-blot. Western-blot was also used to facilitate the observation of ICAM-1 protein expressions in dura maters of rats 0. 5,2. 0,4. 0,6. 0,10. Oh after GTN infusion or 4h after normal saline infusion. The intraperitoneal injection of pyrro-lidine dithiocarbamate (PDTC) (50, 100, 200mg · kg^-1) and 94-95-10Y (10, 20, 30 mg · kg^-1 ) were administered 20min before GTN infusion. DHT infusion (50μg · kg^-1) was administered at GTN infusion 15min. NF-kB and ICAM-1 protein expressions in dura maters of rats were examined 2,4h after normal saline or GTN infusion, respectively. Meanwhile, we examined the inflammatory response in dura maters of rats 2h after normal saline or GTN infusion.ResultsThere are no significant differences in mean arterial blood pressure (MABP) and heart rate (HR) between GTN infusion rats and normal saline infusion rats. Blood vascular dilatation and infiltration of lymphocytes, mono-cytes, neutrophils and plasma cells were found in each group after GTN infusion.The positive NF-kB staining was detected in cell nuclei of dura maters of rats after GTN infusion. The increases of NF-kB protein expression levels in cell nucleus of dura maters of rats appeared 0. 5h after GTN infusion, reached the peak 1. 5h after GTN infusion and then gradually decreased, but the NF-kB protein expression remained beyond normal levels at 2,4h after GTN infusion.The increases of ICAM-1 protein expressions in dura maters of rats were detected 2h after GTN infusion. The increases of the ICAM-1 protein expression levels in dura maters of rats reached the peak 4h after GTN infusion and then gradually decreased, but the ICAM-1 protein expressions remained beyond normal levels at 6, 10h after GTN infusion.After administration of PDTC (50, 100, 200mg · kg^-1) , 94-95-10Y (10, 20, 30mg · kg^-1) and DHT (50μg · kg^-1) , NF-kB and ICAM-1 protein expression levels of dura maters of rats were reduced. 94-95-10Y and DHT alleviated the inflammatory response in dura maters of rats.Conclusions1. GTN infusion with 2μg · kg^-1 · min^-1 induces blood vascular dilatations and infiltrations of inflammatory cells in dura maters of rats, suggesting that GTN infusion accords with the standard of migraine model.2. An early time course consistent with CTN infusion induces the increase of NF-kB protein expression levels in cell nuclei of dura maters of rats, suggesting that NF-kB participates the pathogenesis of migraine.3. A delayed time course consistent with CTN infusion induces the increases of ICAM-1 protein expression levels in dura maters of rats and NF-kB up-regu-lates the increases of ICAM-1 protein expression levels in dura maters of rats after GTN infusion. The blockade of NF-kB expression levels may dedicate a new target in the treatment of migraine.4. 94-95-10Y inhibits the increases of NF-kB protein expression levels in cell nuclei of dura maters of rats. It also inhibits ICAM-1 protein expression levels in dura maters of rats, and alleviates the inflammatory response in dura maters of rats. As a concluding remark, 94-95-10Y might be a prospective anti-mi-...