Fenwick D C, Daniel R C
Department of Physiology and Pharmacology, University of Queensland, St Lucia, Australia.
Br Vet J. 1992 Jul-Aug;148(4):283-99. doi: 10.1016/0007-1935(92)90082-C.
Six HK (high erythrocyte potassium) and 7 LK (low erythrocyte potassium) dairy cows were subjected to a 4-h intravenous infusion of 4.7% Na2EDTA solution to induce and maintain hypocalcaemia. Blood samples taken immediately before infusion, hourly for 7 h, and at 24 h after commencement of infusion were subjected to determination of concentration (or count) of 16 analytes. The mean changes in concentrations (or counts) of the various blood analytes were calculated for the periods 0-4, 4-7, 7-24, and 0-24 h after commencement of the infusion for all cows combined, and then separately for the HK and LK groups of cows. Plasma Ca(PCa), plasma inorganic phosphorus (PiP) and plasma potassium (PK) showed significant decreases during the 4-h infusion period and were still below pretreatment levels 24 h later. AST, CPK, PCVs and white cell-counts (WCCs) showed significant early increases which were still significantly elevated 24 h later. Plasma magnesium (PMg) and erythrocyte Na(ENa) and K(EK) all showed delayed changes which still persisted 24 h later. Significant between-group differences were present for PCVs which increased significantly more in the LK than the HK group during the infusion period, for PCa which showed a greater increase in the HK cows than the LK cows during the 4-7 h early clinical recovery period, and for plasma bilirubin (PBil) which showed a greater increase from 0 to 24 h in the HK group than in the LK group. Urine samples, collected before infusion, 4-7 h and 24 h after commencement of the infusion, were subjected to analysis for glucose, protein, pH, 'blood' and ketones. Most cows showed increases in urinary glucose, protein and 'blood'.
选取6头高红细胞钾（HK）奶牛和7头低红细胞钾（LK）奶牛，静脉输注4.7%的乙二胺四乙酸二钠（Na2EDTA）溶液4小时，以诱导并维持低钙血症。在输注前即刻、输注7小时期间每小时以及输注开始后24小时采集血样，测定16种分析物的浓度（或计数）。计算所有奶牛合并后以及HK和LK奶牛组分别在输注开始后0 - 4、4 - 7、7 - 24和0 - 24小时各血液分析物浓度（或计数）的平均变化。血浆钙（PCa）、血浆无机磷（PiP）和血浆钾（PK）在4小时输注期间显著下降，24小时后仍低于预处理水平。谷草转氨酶（AST）、肌酸磷酸激酶（CPK）、红细胞压积（PCV）和白细胞计数（WCC）早期显著升高，24小时后仍显著高于正常水平。血浆镁（PMg）、红细胞钠（ENa）和红细胞钾（EK）均出现延迟变化，24小时后仍持续存在。红细胞压积在输注期间LK组比HK组显著升高，血浆钙在4 - 7小时早期临床恢复期HK奶牛比LK奶牛升高幅度更大，血浆胆红素（PBil）在0至24小时HK组比LK组升高幅度更大，这些指标组间差异显著。在输注前、输注开始后4 - 7小时和24小时收集尿样，分析葡萄糖、蛋白质、pH值、“潜血”和酮体。大多数奶牛尿中葡萄糖含量、蛋白质含量和“潜血”增加。
