The Determination Of Inorganic Elements In Skeletons Of Gansu Zokor (Myospalax Cansus) And The Analysis About Ca/P Metabolism In Its Skeletons

Skeleton has a great amounts of inorganic elements. As the mineral"sink", the mineral flux between skeleton and other organ,tissue, as the plasma, the gutand the kidney, is the essential way of mineral metabolism. Skeleton mineralmetabolism mainly means the metabolism of Ca and P. Most surface-dwelling animalsreceive sunshine radiation, and mediate absorption and reabsorption of mineralrespectively in intestine and kidney, release and depositon of Ca in skeleton via VitaminD₃-dependent active absoption. Gansu zokor (Myospalax cansus), which is a kind ofherbivorous animal, leads a strictly chthonic existence, perpetually dark and devoid ofultraviolet radiation. They appear to be naturally deficient in vitamin D₃, for the fact thatthey cannot synthesize vitamin D₃ endogenously or attain it from the food. Thus,whether there are differences on contents of inorganic elements in skeletons and Ca/Pmetabolism between Gansu zokor and other surface-dwelling animals. So, weinvestigated inorganic elements in skeletons of Gansu zokor via FAAS (AtomicAbsorption Spectrometry), GFASS (Graphite Furnace Atomic AbsorptionSpectrometry), SP (Spectrophotometry), ISE (Ion Slective Electrode), and comparedresults with data in papers. Then, we compared skeleton Ca/P metabolism betweenGansu zokor and SD rats, both of which accepted oral Ca supplementation, anddiscussed probable mechanism in Ca,P absorption of Gansu zokor.The results are as follow:1. The contents and distributions of the inorganic macroelements—Ca, K, Na, Mg,and P in skeletons of Gansu zokor (Myospalax cansus) were determined by AAS(Atomic Absorption Spectrometry) and SP (Spectrophotometry). The results are asfollows: The contents of these five elements in Gansu zokor, s skeletons are in theturn of Ca＞P＞K＞Na＞Mg. This is mainly due to the food habit. In different parts ofskeletons, contents of these five elements have differences, some of which aresignificant by F-test (p＜0.05). The total amount of these elements is also different indifferent parts: skeletons of forelimb＞skeletons of backlimb＞backbone, and this mayrelate to what importance these skeletons play in when moving. Gansu zokor has anormal content of Ca in skeletons, however, as a kind of solitary subterranean rodent, it has no precondition to synthesize Vitamin D₃—the most important factor to help toabsorb Ca. According to the ratio of Ca to P, these two elements may exist as a form ofCa₁₀(PO₄)₆(OH)₂. in skeletons of Gansu zokor.2. The contents and distributions of the inorganic microelements—Fe,Cu,Zn,Mn,Cr,Ni,Co,Mo,Cd,As,Pb,Al and F in skeletons of Gansu zokor (Myospalaxcansus) were determined by FAAS (Fire Atomic Absorption Spectrometry), GFASS(Graphite Furnace Atomic Absorption Spectrometry), ISE (Ion Slective Electrode) andSP (Spectrophotometry). The results are as follow: The contents of these thirteenelements in Gansu zokor's skeletons are in the turn of Al＞Fe＞Zn＞F＞Mn＞Cu＞Pb＞As＞Cr＞Co＞Ni＞Mo＞Cd. In different parts of skeletons, contnets of mostelements, have significant differences by F-test (P＜0.05), while the others, includingZn and Mn, are not significant (P≥0.05). The contents of inorganic microelements inthe skull are the most. By correlation analysis, there's a significant positive correlationbetween Cu and Fe, Fe and Zn, Co and As, Mo and Cd, As and Cd (0.01＜P＜0.05); asignificant negative correlation between Zn and Pb, Mo and Cd, As and Pb (0.01＜P＜0.05);and a extremely significant positive correlation between Cu and Al, Cu and Ni, Co and Mo,Co and Cd, Co and Pb, Cd and Pb (P＜0.01).3. Gansu zokor and SD rats do or not accept oral Ca supplementation wereinvesgated. Data, including body weight, weight of food intake, contents of Ca and P infemur, concentrations of Ca and P in plasma of four groups, were determined andcompared. Coorrelation and regression analysis between/among contents of Ca/P infemur and amounts of Ca/P ingested, concentrations of Ca/P in plasma. The resultssuggested that Ca supplementation led a marked increase in body weight and foodintake on Gansu zokor. The linear relationship between ingested and femur Ca/P wassignificantly correlated (P＜0.01) of Gansu zokor, while there is not any significance intwo SD rats groups (P＞0.05), implying that this process is nonsaturable. It appears,therefore, this underground inhabitant relies upon highly efficient, passive mineraluptake. This is adequate to meet their mineral requirements and maintain mineralhomeostasis in the absence of vitamin D₃.