Age-Related Changes of Elements in the Tendons of the Peroneus Longus Muscles in Thai, Japanese, and Monkeys

To elucidate compositional changes of the tendon of the peroneus longus muscle with aging, the authors investigated age-related changes of elements in the insertion of tendons of the peroneus longus muscle (peroneus longus tendons) in Thai, Japanese, and monkeys and the relationships among element contents by direct chemical analysis. After ordinary dissections at Chiang Mai University and Nara Medical University were finished, the peroneus longus tendons were resected from the subjects. The peroneus longus tendons were also resected from rhesus and Japanese monkeys bred in Primate Research Institute, Kyoto University. The wraparound regions of the insertion tendons of the peroneus longus muscle in contact with the cuboid bone were used as the peroneus longus tendon. After ashing with nitric acid and perchloric acid, element contents were determined with an inductively coupled plasma-atomic emission spectrometer. It was found that there were no significant correlations between age and the seven elements, such as Ca, P, S, Mg, Zn, Fe, and Na, in the peroneus longus tendons of Thai and Japanese. The Ca content higher than 10 mg/g was contained in seven cases out of 34 peroneus longus tendons of Thai (incidence?=?20.6%) and in one case out of 22 peroneus longus tendons of Japanese (incidence?=?4.5%), respectively. All of the peroneus longus tendons with the Ca content higher than 10 mg/g were found in Thai and Japanese men. In the peroneus longus tendons of monkeys, the Ca and P content increased suddenly at 2 years of age and reached to about 40 mg/g at 5 years of age. Thereafter, the Ca and P content did not increase in the peroneus longus tendons of monkeys at old age. Regarding the relationships among element contents, significant direct correlations were found among the contents of Ca, P, Mg, Zn, and Na in Thai and monkeys, whereas significant inverse correlations were found between S and element contents, such as Ca, P, Mg, Zn, and Na, in Thai and monkeys.     

Age-related changes of elements and relationships among elements in human tendons and ligaments

To elucidate compositional changes of the tendons and ligaments with aging, the authors investigated age-related changes of element contents in the insertion tendons of the biceps brachii muscle, central tendons of the diaphragma, Achilles’ tendons, posterior longitudinal ligaments (PLLs) of the cervical spine, ligamenta capitum femorum, and anterior cruciate ligaments. After ordinary dissections by medical students, the three tendons and three ligaments were resected and element contents were determined by inductively coupled plasma-atomic emission spectrometry. It was found that the elements, such as Ca, P, S, Mg, Na, Zn, and Fe, did not change significantly in the three tendons and two ligaments with aging, except for the PLLs where Ca and Mg increased significantly with aging and Fe decreased significantly with aging. With regard to the relationships among elements, the common finding that there were significant correlations between Ca and P contents and between Ca and Mg contents was obtained in the three ligaments. Likewise, the common finding that there was a significant correlation between Ca and Mg contents was obtained in the three tendons. Regarding the relationship between Ca and P contents, the three tendons were different from the three ligaments.     

Age-Related Changes of Elements in the Anterior Commissures and the Relationships Among their Elements

To elucidate compositional changes of the anterior commissure with aging, the authors investigated age-related changes of elements in the anterior commissures and the relationships among their elements. After ordinary dissection at Nara Medical University was finished, the anterior commissures were resected from 45 subjects, ranging in age from 70 to 101 years. The subjects consisted of 22 men and 23 women. After ashing with nitric acid and perchloric acid, the element content of the anterior commissures was determined by inductively coupled plasma-atomic emission spectrometry. The seven element contents of Ca, P, S, Mg, Zn, Fe, and Na did not change significantly in the anterior commissures with aging. Regarding the relationships among their element contents, significant correlations were found among the contents of Ca, Mg, Zn, and Na in the anterior commissures. The gender difference that the Zn content was significantly higher in men than in women was found in the anterior commissure.     

Age-related changes of elements and relationships among elements in the common bile and pancreatic ducts

To elucidate compositional changes of the common bile and main pancreatic ducts with aging, the authors investigated age-related changes of element contents in the common bile and pancreatic ducts by inductively coupled plasma-atomic emission spectrometry. After ordinary dissection by medical students was finished, the common bile ducts and main pancreatic ducts (pancreatic ducts) were resected and the element contents were determined. The Mg content increased significantly only in the pancreatic duct with aging, but the other element contents did not change significantly in both the common bile and pancreatic ducts with aging. Regarding the relationship among the elements, significant direct correlations were found among the contents of Ca, P, S, and Mg in the common bile ducts, with some exceptions between P and either S or Mg contents. In the pancreatic ducts, significant direct correlations were found between S and Mg contents and between P and Na contents. The relationships in the elements between the common bile and pancreatic ducts were examined. It was found that there were significant direct correlations in the Ca, Mg, and Fe contents between the common bile and pancreatic ducts; that is, as Ca, Mg, and Fe increased in the common bile duct, they increased simultaneously in the pancreatic duct.     

Age-Related Changes of the Concentrations of Select Elements in the Prostates of Japanese

To elucidate compositional changes of the prostate with aging, the authors investigated age-related changes of elements in the prostates and the relationships among their elements using Japanese and Thai. After ordinary dissections by students at Nara Medical University and Chiang Mai University were finished, the prostates were resected from the subjects. Fifty-seven Japanese subjects ranged in age from 65 to 101 years (average age = 82.5 ± 7.8 years), whereas 13 Thai subjects ranged in age from 43 to 86 years (average age = 67.9 ± 11.9 years). After ashing with nitric acid and perchloric acid, element contents were determined by inductively coupled plasma–atomic emission spectrometry. It was found that although there were no significant correlations between age and seven element contents, such as Ca, P, S, Mg, Zn, Fe, and Na, in the prostates of Japanese, high contents of Ca (>5 mg/g) and P (>4 mg/g) were contained in one fourth of the prostates of Japanese over 70 years of age. In the prostates of Thai, a significant direct correlation was found between age and Ca content, but it was not found between age and the other element contents, such as P, S, Mg, Zn, Fe, and Na. Regarding the relationships among their elements, extremely significant direct correlations were found among the contents of Ca, P, Mg, Zn, and Na in the prostates of Japanese. In the prostates of Thai, significant direct correlations were found among the contents of Ca, Mg, and Zn, but no significant correlations were found between Ca and P contents and between P and Mg contents. Regarding the relationships among their elements, there were differences between the prostates of Japanese and Thai. To examine whether element contents changed in prostatic hypertrophy, the transverse width of the Japanese prostates was measured. No significant correlations were found between the transverse width and element contents, such as Ca, P, S, Mg, Zn, Fe, and Na, in the Japanese prostates. Therefore, it is unlikely that the increase of elements results in prostatic hypertrophy.     

Age-Related Changes of Elements in Human Olfactory Bulbs and Tracts and Relationships Among Their Contents

To elucidate compositional changes of the olfactory bulb and tract with aging, the authors investigated age-related changes of elements in the olfactory bulbs and tracts of Japanese and the relationships among the elements. After ordinary dissection at Nara Medical University was finished, the olfactory bulbs were resected with the olfactory tracts from 40 subjects. The subjects consisted of 15 men and 25 women, ranging in age from 65 to 102 years (average age = 84.6 +/- 7.5 years). After ashing with nitric acid and perchloric acid, element contents in the olfactory bulbs and tracts were analyzed by inductively coupled plasma-atomic emission spectrometry. Seven elements of Ca, P, S, Mg, Zn, Fe, and Na did not change significantly in the olfactory bulbs and tracts with aging. The Ca, P, and S contents of major elements were less than 10 mg/g in all of the olfactory bulbs and tracts. Regarding the relationships among the elements, extremely or very significant direct correlations were found among the contents of Ca, P, Mg, Zn, and Na in the olfactory bulbs and tracts, with one exception. In addition, an extremely significant direct correlation was found between S and Mg contents and a very significant direct correlation was found between P and S contents. As P increased in the olfactory bulb and tract, Ca, Mg, Zn, Na, and S also increased in the olfactory bulb and tract.     

Age-Related Changes of Elements and Relationships Among Elements in Human Hippocampus, Dentate Gyrus, and Fornix

To elucidate compositional changes of the limbic system with aging, the authors investigated age-related changes of elements in the hippocampus, dentate gyrus, and fornix and the relationships among elements by direct chemical analysis. After ordinary dissections at Nara Medical University were finished, the hippocampi, dentate gyri, and fornices were resected from identical cerebra of the subjects which consisted of 23 men and 23 women, ranging in age from 70 to 101 years. After ashing with nitric acid and perchloric acid, element contents were determined by inductively coupled plasma-atomic emission spectrometry. The average contents of P, Zn, and Na were significantly less in both the hippocampi and dentate gyri compared with the fornices. It was found that the Ca and Mg contents increased significantly in the hippocampus with aging; the P content increased significantly in the dentate gyrus with aging, whereas the Na content decreased in the dentate gyrus with aging; and the Mg content increased significantly in the fornix with aging. Regarding the relationships among elements, a significant direct correlation between Ca and Fe contents and an extremely significant inverse correlation between P and Zn contents were found in both the hippocampi and dentate gyri. In addition, a significant direct correlation between P and Mg contents was found in both the hippocampi and fornices. Pearson's correlation was used to examine whether there were elements with significant correlation among the hippocampus, dentate gyrus, fornix, and mammillary body. Significant correlations were found in five elements of Ca, P, Mg, Zn, and Fe except for S and Na among the hippocampus, dentate gyrus, and mammillary body with one exception. Regarding the fornix, significant correlations were found in two elements of P and Fe between the fornix and hippocampus, dentate gyrus, or mammillary body.     

Calcium Increase in the Mammillary Bodies with Aging

To elucidate compositional changes of the mammillary body with aging, the authors investigated age-related changes of elements, relationships among their elements, and gender differences in the mammillary bodies by direct chemical analysis. After ordinary dissection at Nara Medical University was finished, the mammillary bodies were resected from the cerebra of the subjects. The subjects consisted of 19 men and 25 women, ranging in age from 70 to 101 years (average age?=?83.8?±?7.2 years). After ashing of the mammillary bodies with nitric acid and perchloric acid, element contents were determined by inductively coupled plasma–atomic emission spectrometry. It was found that the Ca content increased slightly and significantly in the mammillary bodies with aging, but the P, S, Mg, Zn, Fe, and Na contents did not change significantly with aging. Regarding the relationships among elements, significant correlations were found among the contents of Ca, P, S, and Mg in the mammillary bodies, with one exception between P and Mg contents. With regard to the seven element contents, no significant gender differences were found in the mammillary bodies.     

Age-related Changes of Elements in Human Corpus Callosum and Relationships Among These Elements

To elucidate compositional changes of the corpus callosum with aging, the authors investigated age-related changes of elements and relationships with their element contents in the corpus callosum. After ordinary dissection by medical students at Nara Medical University was finished, the genu, trunk, and splenium of the corpus callosum were resected from the subjects ranging in age from 58 to 94 years. The element contents of the corpus callosum were determined by inductively coupled plasma-atomic emission spectrometry. The contents of Ca, P, S, Mg, Zn, Fe, and Na did not change significantly in the genu, trunk, and splenium of the corpus callosum with aging. Regarding the relationships among the element contents, significant correlations were found among the contents of Ca, P, S, Mg, and Fe in all of the genu, trunk, and splenium of the corpus callosum with some exceptions.     

Age-Related Decrease of the Phosphorus Content in the Ligamentum Capitis Femoris of Monkeys

To elucidate compositional changes of the ligament with aging, the authors investigated age-related changes of elements in the ligamentum capitis femoris (LCF) of monkeys with a wide range of ages by direct chemical analysis. Used rhesus and Japanese monkeys consisted of 9 males and 22 females, ranging in age from newborn to 31 years (average age?=?10.4?±?10.9 years). After incineration with nitric acid and perchloric acid, element contents were determined by inductively coupled plasma-atomic emission spectrometry. It was found that the P content decreased significantly in the LCFs of monkeys with aging, but other six element contents, Ca, S, Mg, Zn, Fe, and Na, did not change significantly with aging. Assuming that the P content indicated the active cell density and the S content indicated the protein amount, an age-related change of the mass ratio of P/S was examined in the LCFs. The mass ratio of P/S decreased significantly in the LCFs in childhood. Regarding the relationships among elements, significant direct correlations were found among the Ca, P, S, and Mg contents in the LCFs. It was suggested that the active cell density of the connective tissue cells might decrease significantly in the LCF in childhood.     

Age-dependent decreases of sulfur and magnesium in human round ligaments of the uterus and relationships among elements

To elucidate the compositional change of ligaments with aging, the authors investigated both age-related changes of elements and relationships among elements in the round ligaments of the uterus (round ligaments) by inductively coupled plasma-atomic emission spectrometry. The bilateral round ligaments were resected from 20 cadavers and also from the uteri removed surgically from 11 patients bearing uterine myoma or cancer. Thirty-one subjects ranged in age from 34 to 92 yr. It was found that both S and Mg decreased gradually in the round ligaments with aging, but Ca, P, Zn, Fe, and Al did not change significantly with aging. Regarding the relationships among elements, very significant direct correlations were found among the contents of Ca, P, S, and Mg in the round ligaments, whereas significant inverse correlations were found between the contents of Zn and elements, such as Ca, P, S, and Mg. It should be noted that there was an extremely significant direct correlation between Ca and P contents in the round ligaments.     

Increases of calcium and phosphorus in the uterine arteries with aging

To elucidate compositional changes of the uterine artery with aging, the authors investigated age-related changes of elements in the uterine arteries. After ordinary dissection by medical students at Nara Medical University was finished, the uterine arteries were resected from the subjects. The element content of the uterine arteries was analyzed by inductively coupled plasma-atomic emission spectrometry. The subjects ranged in age from 58 to 99 yr (average age=82.7±10.1 yr). It was found that the Ca, P, and Na contents increased progressively in the uterine arteries with aging. A significant accumulation of Ca and P in the uterine arteries was found in the sixties and increased markedly in the eighties. It should be noted that as far as the arteries in those over 70 yr of age, the extent of accumulation of Ca and P was the highest in the uterine arteries within the limits of the arteries analyzed by us. Regarding the relationships among elements, significant direct correlations were found among the contents of Ca, P, Mg, Zn, and Na. As Ca increased in the uterine arteries, P, Mg, Zn, and Na increased simultaneously in the arteries.     

Age-dependent Increases of Calcium, Phosphorus, and Sodium in the Uterine Arteries of Thai

To elucidate compositional changes of the uterine artery with aging, the authors investigated age-related changes of elements in the uterine arteries of Thai. After ordinary dissection by medical students at Chiang Mai University was finished, the uterine arteries were resected from Thai subjects. Thai subjects ranged in age from 27 to 86 years (average age = 63.3 +/- 17.7 years). The element content of the uterine arteries was analyzed by inductively coupled plasma-atomic emission spectrometry. It was found that the Ca, P, and Na contents increased progressively in the uterine arteries of Thai with aging. A significant accumulation of Ca and P in the uterine arteries of Thai was found in the sixties patients, and the accumulation increased markedly in the seventies. Regarding the uterine arteries in subjects more than 60 years, the extent of accumulation of Ca and P in the uterine arteries of Thai was one half of that in the uterine arteries of Japanese. Regarding the relationships among elements, extremely significant direct correlations were found among the contents of Ca, P, Mg, Zn, and Na in the uterine arteries of Thai. As Ca increased in the uterine arteries of Thai, P, Mg, Zn, and Na increased simultaneously in the arteries.     

Scarce Occurrence of Calcification in Human Sinoatrial Nodal Arteries in Old Age

To elucidate age-related changes of the sinoatrial (sinuatrial) nodal (SAN) artery, the authors investigated age-related changes of elements in the SAN artery by direct chemical analysis. In addition, the effects of different arterial origins, arterial sizes, and genders on element accumulation were investigated in the SAN artery. Fifty-nine formalin-fixed adult Thai hearts were dissected, and the following three types of the SAN artery were found: The first type was a single SAN artery arising from the right coronary artery (RCA). The second type was a single SAN artery arising from the proximal segment of the left circumflex artery (LCX). The third type was dual SAN artery arising from both the RCA and the LCX. For element analysis, both 41 single SAN arteries arising from the RCA and the LCX and 18 larger branches of dual SAN artery were used. After the arteries were incinerated with nitric acid and perchloric acid, element contents were determined by inductively coupled plasma-atomic emission spectrometry. It was found that seven element contents such as Ca, P, S, Mg, Zn, Fe, and Na did not change significantly in the SAN arteries with aging. Regarding the relationships among seven elements in the SAN arteries, extremely significant direct correlations were found among P, S, Mg, and Fe contents with one exception. However, no significant correlations were found between Ca and either P or Mg contents in the SAN arteries. To examine an effect of the different arterial origins on element accumulation, the SAN arteries were separated into the RCA and the LCX groups by the arterial origin and age-related changes of element contents were compared between two groups. It was found that there were no significant differences between the RCA and the LCX groups in age-related changes of Ca and P contents. No gender differences were found in age-related changes of Ca and P contents in the SAN arteries. To elucidate whether calcification occurred in the SAN arteries in old age, both the mass ratios of Ca/P and Mg/Ca were estimated in the SAN arteries. The mass ratio of Ca/P increased progressively in the SAN arteries with Ca increase, being not constant. The mass ratio of Mg/Ca decreased gradually in the SAN arteries with Ca increase, but the average mass ratio of Mg/Ca was very high, being 49.4 ± 16.5%. These results indicated that calcification scarcely occurred in the SAN arteries in old age, independently of the arterial origin and gender.     

Compositional changes of human mitral valves with aging

To elucidate compositional changes of the mitral valve with aging, the authors investigated the relationships among element contents in the mitral valves. The subjects consisted of 10 men and 15 women, ranging in age from 65 to 102 yr. After the ordinary dissection, mitral valves, lower parts of the interventricular septa, and terminal crests containing the sinoatrial nodes were resected and the element contents were determined by inductively coupled plasma-atomic emission spectrometry. The interventricular septa and sinoatrial nodes were used to compare with the mitral valves. With regard to the mitral valve, it was found that extremely significant correlations were found among the contents of Ca, P, Mg, and Na, but no significant correlations were found between the contents of S and elements such as Ca, P, or Mg. Regarding the interventricular septum, it was found that an extremely significant correlation was found between P and S contents; very significant correlations were found between Ca and Mg contents and between Mg and S contents; and a significant correlation was found between P and Mg contents. However, no significant correlation was found between Ca and P contents in the interventricular septa. In the terminal crest containing the sinoatrial node, significant correlations were found among the contents of Ca, P, Mg, and S. The present study revealed that with regard to the relationships among element contents, the compositional change of the mitral valve was intermediate between those of the thoracic aorta and the interventricular septum.     

Element Distribution in Visual System,the Optic Chiasma,Lateral Geniculate Body,and Superior Colliculus

To elucidate compositional changes of the visual system with aging, the authors investigated age-related changes of elements in the optic chiasma, lateral geniculate body, and superior colliculus, relationships among their elements, relationships among their brain regions from a viewpoint of elements, and gender differences in their elements by direct chemical analysis. After ordinary dissection at Nara Medical University was finished, the optic chiasmas, lateral geniculate bodies, and superior colliculi were resected from identical cerebra of the subjects. The subjects consisted of 14 men and 10 women, ranging in age from 75 to 96 years (average age = 85.6 ± 5.9 years). After ashing with nitric acid and perchloric acid, element contents were determined by inductively coupled plasma-atomic emission spectrometry. As the result, the average content of P was significantly higher in the optic chiasma and superior colliculus compared with the lateral geniculate body. Regarding age-related changes of elements, no significant changes with aging were found in seven elements of the optic chiasma, lateral geniculate body, and superior colliculus in the subjects more than 75 years of age. The findings that with regard to the relationships among elements, there were extremely significant direct correlations between Ca and Zn contents and significant inverse correlations between Mg and Na contents were obtained in common in all of the optic chiasma, lateral geniculate body, and superior colliculus. It was examined whether there were significant correlations among the optic chiasma, lateral geniculate body, and superior colliculus in the seven elements and the following results were obtained: There were significant direct correlations between the optic chiasma and lateral geniculate body in both the P and Mg contents; there was a significant direct correlation between the optic chiasma and superior colliculus in the Fe content; and a significant direct correlation was found between the lateral geniculate body and superior colliculus in the Mg content. Regarding the gender differences in elements, it was found that both the Ca and Zn contents of the lateral geniculate body were significantly higher in women than in men.     

Age-Related Differences and Relationships Between Elements in Human Amygdala and Other Limbic System or Basal Ganglia

To elucidate the compositional changes of the amygdala with aging, the authors investigated age-related differences of elements in human amygdalae. In addition, the relationships between the amygdala and other brain regions were investigated from a viewpoint of elements. After ordinary dissections at Nara Medical University were finished, the amygdalae were removed from the cerebra of the subjects who consisted of 22 men and 23 women, ranging in age from 70 to 101 years. In addition, the hippocampus, dentate gyrus, mammillary body of the limbic system and the caudate nucleus, putamen, and globus pallidus of the basal ganglia were also removed from the identical cerebra. After the brain samples were incinerated with nitric acid and perchloric acid, the element contents were determined by inductively coupled plasma-atomic emission spectrometry. It was found that both the Ca and Mg contents increased significantly in the amygdalae with aging, but the other five element contents (P, S, Zn, Fe, and Na) did not change significantly in the amygdalae with aging. Regarding the relationships among elements, very significant or significant direct correlations were found among the Ca, P, and Mg contents in the amygdalae. To explore the relationships between the amygdala and either other limbic system or basal ganglia, the correlations between seven elements of the amygdala and hippocampus, dentate gyrus, or mammillary body, and between those of the amygdala and caudate nucleus, putamen, or globus pallidus which derived from the identical cerebra, were analyzed with Pearson’s correlation. It was found that regarding the four elements of Ca, P, Mg, and Fe, a close relationship existed between the amygdala and hippocampus, globus pallidus, or mammillary body.     

Age-related changes of elements in thoracic and abdominal aortas and coronary, common carotid, pulmonary, splenic, common iliac, and uterine arteries and relationships in elements among their arteries

To elucidate whether the accumulation of elements occurred simultaneously in the various arteries with aging, the authors investigated age-related changes of elements in the eight arteries, such as the thoracic and abdominal aortas and the coronary, common carotid, pulmonary, splenic, common iliac, and uterine arteries, and the relationships in the element contents among their arteries. After ordinary dissection by medical students was finished, the thoracic and abdominal aortas and the coronary, common carotid, pulmonary, splenic, common iliac, and uterine arteries were resected from the subjects, who ranged in age from 58 to 94 yr. The element contents were analyzed by inductively coupled plasma-atomic emission spectrometry. It was found that the accumulation of Ca was the highest in the common iliac artery and decreased in the order of the uterine artery, abdominal aorta, coronary artery, thoracic aorta, splenic artery, common carotid artery, and pulmonary artery. Regarding the relationships in the element contents among the eight arteries, it was found that there were significant direct correlations in the contents of Ca, P, Mg, Zn, Fe, and Na between the coronary and splenic arteries, and there were significant correlations in the contents of Ca, P, and Mg between the abdominal aorta and pulmonary artery.     

Studies on the Characteristic of Element Contents in the Dominant Plant Species of the Three gorges Region in China

The characteristics of the contents of 20 elements (Al, Fe, Mn, Ca, Mg, K, S, Si, P, Cd, Cu, Zn, Ti, Ni, Sr, Mo, Na, B, Cr, V) in 16 plant species collected from the Three Gorges Region in China were investigated. The average contents of Ca, K and Mg were higher than 1 000 μg·g-1, that of Al, P, Si, Fe, S and Mn ranged between 100—1 000 μg·g-1 and Ti, Cu, Ni, Cr, Mo, Cd and V were less than 10 μg·g- 1. The level of Na content was less than that of the reported. The main character of the element contents was of the Ca> K type. The contents of P, S, Ca and K in different plant samples showed a normal distribution pattern, while Al and Mn showed a elements lognormal distribution pattern. Plant species differed greatly in the element contents. On analyzing the coefficient of variation (C. V., % ), Al, Mn, Mg, Ni, Sr and Fe had higher C.V., while the C.V. of K, S, P, Cr, Cd and Cu was less than 60%, and Cu had the lowest C.V. The correlations between Al and Fe, Al and Ti, Al and Cr, A1 and V, Cd and Sr, Cd and Mo, Fe and V, Zn and Cr, Ni and Sr, Mg and Ni, Mo and Sr, Ca and Sr, Cr and Mo, Na and Mg, Na and P, P and S were statistically significant in different plant species. The classification of the 16 plant species and 20 dements by two-way indicator species analysis (TWINSPAN) method may suggest the difference in dement contents of the different plant species.     

Age-related attenuation in the elements in monkey sino-atrial node

Changes in trace elements of the sino-atrial (SA) node with aging was investigated using 24 hearts of the Japanese and rhesus monkeys of ages ranging from 27 d to 30 yr. With aging, sympathetic activity decreases and SA nodal function deterionates. The SA nodal tissue was removed from the anatomical position and was confirmed by means of histological observation. The elements, such as Ca, P, S, Mg, Na, Fe, and Zn, were analyzed using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Advancing age never increased the contents of the trace elements, but decreased them. The correlation coefficients for the age-dependent attenuations were −0.561 (n=24, p<0.01) in Ca and −0.482 (n=24, p<0.05) in P. The correlations for the attenuations induced by other trace elements were not significant. Furthermore, close relationships of the elements between Ca and P, S, Zn, or Na contents, between P and Zn or Na contents, and between Zn and Na contents were observed. These results indicate that the elements in the monkey SA node are attenuated with an increase in age, presumably suggesting the age-related suppression of cardiac functions as a result of the histological alterations of the SA nodal cells.