Prolactin induced cyto-architectural changes in the corpuscles of Stannius of stinging catfish, Heteropneustes fossilis acclimated to different calcium media

Adult fish Heteropneustes fossilis were divided into 4 groups –(i) Group A: kept in artificial freshwater and daily injected intraperitoneally with vehicle; (ii) Group B: kept in artificial freshwater and were daily injected intraperitoneally with 0.1 mg/100 g body wt of oProlactin; (iii) Group C: maintained in calcium-deficient freshwater and daily injected intraperitoneally with vehicle; (iv) Group D: kept in calcium-deficient freshwater and daily injected intraperitoneally with 0.1 mg/100 g body wt of oProlactin. Blood samples were taken 2 h after the last injection on 1, 3, 5, 10 and 15 days of the treatment. Plasma calcium levels were analyzed. The corpuscles of Stannius (CS) were fixed for histological studies. Artificial freshwater: The plasma calcium levels of vehicle-injected specimens (group A) remained unaltered throughout the experiment. Following prolactin treatment (group B) the plasma calcium levels progressively increased from day 3 to day 5. The values became normocalcemic at day 10 and day 15. After day 5 following prolactin administration (group B), the nuclear volume of AF-positive cells increased and the cells were seen degranulated. After day 10, there was an increased dilatation of sinusoids and the nuclear volume of AF-positive cells showed further increase. On day 15, these changes were exaggerated. The AFnegative cells of the corpuscles of Stannius of prolactin-treated fish (group B) showed no change in their histological structure and nuclear volume. Calcium-deficient freshwater: The plasma calcium level decreased in vehicle-injected fish (group C) from day 1 to day 3 (as compared to level of the fish kept in artificial freshwater). Thereafter, the level increased from day 5 resulting in hypercalcemia at day 10 and day 15. In prolactin treated fish (group D) the plasma calcium level indicated progressive increase from day 5 to day 15. In the vehicle-injected fish (group C) the AF-positive cells of corpuscles of Stannius showed accumulati

Altered vitamin D3 metabolism in the ovary and periovarian adipose tissue of rats with letrozole-induced PCOS

Vitamin D3 (VD3) plays an important role in the ovary and its deficiency is associated with ovarian pathologies, including polycystic ovary syndrome (PCOS). However, there is no data related to VD3 metabolism in the ovary during PCOS. Herein, we investigated differences in the expression of VD3 receptor (VDR) and key VD3 metabolic enzymes, 1α-hydroxylase (CYP27B1) and 24-hydroxylase (CYP24A1), in the ovary and periovarian adipose tissue (POAT) of control (proestrus and diestrus) and PCOS induced by letrozole rats. Vdr, Cyp27b1 and Cyp24a1 mRNA expression was determined, their protein abundance was examined and immunolocalized. Furthermore, VD3 metabolite concentrations in plasma (25OHD) and tissues (ovary and POAT; 1,25(OH)2D3), and plasma calcium level were determined. 25OHD concentration decreased markedly in letrozole-treated rats in comparison with controls, whereas calcium concentration did not vary among the examined groups. The amount of 1,25(OH)2D3 decreased in both ovary and POAT of PCOS rats. In the ovary, we found decreased Cyp27b1 and increased Vdr mRNA expression in letrozole-treated and diestrus control group. Corresponding protein abundances were down-regulated and up-regulated, respectively but only following letrozole treatment. In POAT, only Cyp27b1 transcript level and CYP27B1 protein abundance were decreased in letrozole-treated rats. VDR was immunolocalized in healthy and cystic follicles, while CYP27B1 and CYP24A1 were found exclusively in healthy ones. Concluding, our results provide the first evidence of disrupted VD3 metabolism in the ovary and POAT of PCOS rats. The reduced 1,25(OH)2D3 concentration in those tissues suggests their contribution to VD3 deficiency observed in PCOS and might implicate in PCOS pathogenesis.

A rare case of acute kidney injury and anemia induced by hypercalcemia

Hypercalcemia may result in acute kidney injury (AKI) and arterial hypertension. Anemia as a consequence of this constellation is nowhere described. A female patient underwent total thyroidectomy in 2007, since then being under continuous daily medication with 100 μg thyroxin, 1.6 g calcium and 1.0 μg alfacalcidol. In 2017, after accidentally overdosing alfacalcidol fourfold for several weeks leading to massive hypercalcemia (plasma calcium level 16.7 mg/dL), the otherwise healthy patient developed symptoms of AKI, such as serum creatinine 2.48 mg/dL, plus severe hypertension and acute anemia (hemoglobin concentration 10.2 g/dL). After cessation of calcium and alfacalcidol medication for 9 days, hypercalcemia and AKI symptoms and anemia recovered within 14 and after 62 days, respectively. The patient is currently free of complaints and has been sufficiently treated with half of the yearslong pre-event calcium/alfacalcidol dose. In conclusion, hypercalcemia with consecutive AKI after vitamin D overdose can occur asymptomatically. The treatment does not compulsorily include washout by hyperhydration and diuretics. AKI may lead to anemia, possibly caused by the deterioration of the release of erythropoietin.

1,25(OH)2D3 Induced Alterations in Plasma Calcium, Inorganic Phosphate, Ultimobranhial Gland and Parathyroid Gland of the Garden Lizard, Calotes Versicolor

1,25(OH)2D3Induced Alterations in Plasma Calcium, Inorganic Phosphate, Ultimobranhial Gland and Parathyroid Gland of the Garden Lizard,Calotes VersicolorGarden lizardsCalotes versicolorwere procured and given daily intraperitoneal injections of 30 pmol of 1,25(OH)2D3/50 g body wt for 30 days. Lizards were sacrificed on the 1st, 3rd, 5th, 10th, 15thand 30thday of the experiment. The plasma calcium levels ofC. versicolorremain unaffected after day 1 following 1,25(OH)2D3treatment. After day 3 the levels increase significantly which progresses up to day 10. Thereafter, the plasma calcium level tends to decrease on day 15 and the levels become normal at day 30. In 1,25(OH)2D3injected lizards the plasma inorganic phosphate levels remain unaltered up to day 3. After day 5, the value increases significantly. This increase progresses up to day 15. On day 30, the levels become almost normal. The ultimobranchial gland exhibits hyperactivity following 5 day 1,25(OH)2D3treatment which is expressed by an increase in the nuclear volume and weak staining response of the cytoplasm of ultimobranchial cells. After day 10, the nuclear volume is further increased and some of the cells are exhausted. Following 15 days 1,25(OH)2D3treatment the nuclear volume records an increase and many degenerating cells are discerned. After day 30, the nuclear volume is almost normal, most cells seem to be recovered and only a few degenerating cells are noticed. After day 10 and day 15 following 1,25(OH)2D3treatment, the parathyroid glands ofC. versicolorshow reduced chromaticity of nuclei and a progressive decrease in the nuclear volume of parathyroidal cells. On day 30, the nuclear volume tends to become normal and a few degenerating cells are observed.

Effect of vitamin D3 on duodenal calcium absorption in vivo during early development

The effect of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and vitamin D deficiency on duodenal calcium absorption in suckling and weaned rats was determined by an in situ loop technique. In vitamin D-replete (+D) rats, the linear, or nonsaturable, component of calcium absorption was very efficient in 14-day-old pups and decreased with age until 35 days. The saturable component, which was undetectable in 14-day-old pups, became detectable by 18 days of age and increased until 26 days of age. Calcium absorption was not reduced in vitamin D-deficient (-D) 14-day-old pups as compared with +D pups. A high dose of 1,25(OH)2D3 increased the plasma calcium level of +D suckling rats but had no effect on calcium absorption even with milk present in the loop. Weaned -D rats had a reduced saturable component of absorption (P less than 0.01) compared with +D rats. A high dose of 1,25(OH)2D3 significantly increased calcium absorption and plasma calcium levels of -D rats. Our results indicate that during suckling calcium absorption occurs by a process that is insensitive to vitamin D. After weaning both saturable and nonsaturable processes appear to contribute to calcium absorption, and the saturable component can be influenced by vitamin D status or a high dose of 1,25(OH)2D3.