Pakkanen Soile Anja Eliisa, de Vries Annemarie, Raekallio Marja Riitta, Mykkänen Anna Kristina, Palviainen Mari Johanna, Sankari Satu Marja, Vainio Outi Maritta
Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, P.O. Box 57, 00014, Helsinki, Finland.
Davies Veterinary Specialists, Manor Farm Business Park, Higham Gobion, Hertfordshire, UK.
Acta Vet Scand. 2018 May 9;60(1):27. doi: 10.1186/s13028-018-0380-x.
Romifidine, an α-2 adrenoceptor agonist, is a widely-used sedative in equine medicine. Besides the desired sedative and analgesic actions, α-2 adrenoceptor agonists have side effects like alterations of plasma concentrations of glucose and certain stress-related hormones and metabolites in various species. Vatinoxan (previously known as MK-467), in turn, is an antagonist of α-2 adrenoceptors. Because vatinoxan does not cross the blood brain barrier in significant amounts, it has only minor effect on sedation induced by α-2 adrenoceptor agonists. Previously, vatinoxan is shown to prevent the hyperglycaemia, increase of plasma lactate concentration and the decrease of insulin and non-esterified free fatty acids (FFAs) caused by α-2 adrenoceptor agonists in different species. The aim of our study was to investigate the effects of intravenous romifidine and vatinoxan, alone and combined, on plasma concentrations of glucose and some stress-related hormones and metabolites in horses.
Plasma glucose concentration differed between all intravenous treatments: romifidine (80 μg/kg; ROM), vatinoxan (200 μg/kg; V) and the combination of these (ROM + V). Glucose concentration was the highest after ROM and the lowest after V. Serum FFA concentration was higher after V than after ROM or ROM + V. The baseline serum concentration of insulin varied widely between the individual horses. No differences were detected in serum insulin, cortisol or plasma adrenocorticotropic hormone (ACTH) concentrations between the treatments. Plasma lactate, serum triglyceride or blood sodium and chloride concentrations did not differ from baseline or between the treatments. Compared with baseline, plasma glucose concentration increased after ROM and ROM + V, serum cortisol, FFA and base excess increased after all treatments and plasma ACTH concentration increased after V. Serum insulin concentration decreased after V and blood potassium decreased after all treatments.
Romifidine induced hyperglycaemia, which vatinoxan partially prevented despite of the variations in baseline levels of serum insulin. The effects of romifidine and vatinoxan on the insulin concentration in horses need further investigation.
罗米非定是一种α-2肾上腺素能受体激动剂，是马医学中广泛使用的镇静剂。除了预期的镇静和镇痛作用外，α-2肾上腺素能受体激动剂在各种物种中具有副作用，如血糖以及某些应激相关激素和代谢物的血浆浓度改变。相反，瓦替诺生（以前称为MK-467）是α-2肾上腺素能受体的拮抗剂。由于瓦替诺生不会大量穿过血脑屏障，因此它对α-2肾上腺素能受体激动剂诱导的镇静作用影响较小。以前的研究表明，瓦替诺生可预防不同物种中由α-2肾上腺素能受体激动剂引起的高血糖症、血浆乳酸浓度升高以及胰岛素和非酯化游离脂肪酸（FFA）减少。我们研究的目的是调查静脉注射罗米非定和瓦替诺生单独及联合使用对马血浆葡萄糖浓度以及一些应激相关激素和代谢物的影响。
所有静脉注射治疗之间的血浆葡萄糖浓度有所不同：罗米非定（80μg/kg；ROM）、瓦替诺生（200μg/kg；V）以及两者的组合（ROM+V）。葡萄糖浓度在注射罗米非定后最高，在注射瓦替诺生后最低。血清FFA浓度在注射瓦替诺生后高于注射罗米非定或ROM+V后。个体马匹之间胰岛素的基线血清浓度差异很大。各治疗组之间的血清胰岛素、皮质醇或血浆促肾上腺皮质激素（ACTH）浓度未检测到差异。血浆乳酸、血清甘油三酯或血钠和血氯浓度与基线相比或各治疗组之间没有差异。与基线相比，注射罗米非定和ROM+V后血浆葡萄糖浓度升高，所有治疗后血清皮质醇、FFA和碱剩余升高，注射瓦替诺生后血浆ACTH浓度升高。注射瓦替诺生后血清胰岛素浓度降低，所有治疗后血钾降低。
罗米非定诱导高血糖症，尽管血清胰岛素基线水平存在差异，但瓦替诺生可部分预防。罗米非定和瓦替诺生对马胰岛素浓度的影响需要进一步研究。
