Effects of zinc and/or iron deficiency on rectal temperature in rats

A possible role of plasma aldosterone in hypotension secondary to iron-deficiency anaemia combined with zinc deficiency in rats

Patients with Fe-deficiency anaemia are often afflicted by hypotension. However, the mechanism of secondary hypotension in Fe-deficiency anaemia is unknown. To investigate the pathogenesis of secondary hypotension in Fe-deficiency anaemia, we examined the effects of Fe deprivation on plasma aldosterone concentration and blood pressure in rats. A total of forty 4-week-old male Sprague–Dawley rats were assigned into four treatment groups of ten each for the 4-week study: Fe-deficient group (FD), Zn-deficient group (ZD), Fe/Zn-deficient group (FZD) and control group (CON). At days 26 and 27, blood pressure was measured by the tail-cuff method. Plasma aldosterone concentration was determined by ELISA. The data were analysed by Tukey's multiple comparison test. Rats in the FZD had significantly lower mean blood pressure (P < 0·01) and diastolic blood pressures (P < 0·05) and plasma aldosterone concentration (P < 0·01) compared to the CON. These results suggest that blood pressure is decreased in Fe-deficiency anaemia combined with Zn deficiency partly due to decreased circulating aldosterone concentrations in addition to decreased haematocrit.

Gender-related differences in a process of the age-dependent alterations of the elements in monkey sino-atrial node

Gender differences in the trace elements of monkey sino-atrial (SA) node were investigated in a process of age-dependent alterations. Sixty hearts from Japanese and rhesus monkeys (30 male and 30 female) used were aged ranging from 1-day- to 30-year-old. The elements were analyzed using an inductively coupled plasma-atomic emission spectrometer (ICP-AES). Advancing age decreased all the trace elements. Ca, P, S and Mg significantly decreased. The correlation coefficients of Ca and P were -0.178±0.081 (p<0.05) and -0.088±0.022 (p<0.05) in male (n=30), and -0.095±0.026 (p<0.05) and -0.069±0.017 (p<0.05) in female (n=30), respectively. The age-dependent coefficients for Fe/Ca, Zn/Ca, Fe/P, Fe/S, Zn/S, Fe/Mg and Zn/Mg were exhibited markedly in male, but all was less in female. In gender-related differences, only a ratio of P/Ca (p<0.05) was significantly observed with ageing. The trace elements such as Cu, Se and Sn were less detected in the SA nodes. These results indicate that the age-dependent changes in the ratios of elements are appeared more rapidly in male monkey SA node, and the gender difference is observed in ratio of P/Ca. The different attenuations may be involved with the age- and gender-related SA nodal functions.