Our objective was to evaluate the maternal-fetal transfer of melatonin in pregnant women. Serum melatonin concentration was measured by high-performance liquid chromatography with electrochemical detection in a maternal vein and in the umbilical artery and umbilical vein at the time of birth. Blood samples were obtained from 12 women who had spontaneously delivered vaginally at night. A single oral dose of melatonin was administered to each of 33 patients who underwent a cesarean section, and, blood samples were taken at 1, 2, 3, or 4 hr after the administration of melatonin at delivery. Cesarean section was performed between 1300 and 1500 hr. The mean melatonin concentrations of melatonin in maternal peripheral venous blood and umbilical arterial and umbilical venous blood did not differ significantly, and positive correlations in the serum levels of melatonin were observed between the three sources of blood. The oral administration of 3 mg of melatonin to pregnant women led to marked increases in the serum levels of melatonin, with maximum levels observed 2 hr (21.84 +/- 2.09 ng/ml) after drug administration. Changes in serum levels of melatonin in the umbilical vein and artery resembled those found in the maternal vein. Serum melatonin concentrations did not differ significantly between the maternal vein and the umbilical veins. Serum levels of melatonin in the umbilical vein after the administration of melatonin were significantly and closely correlated with those in the maternal vein (r = 0.924, P < 0.001). These results suggest that, in humans, melatonin is transferred from the maternal to the fetal circulation both easily and rapidly. A potential for the therapeutic use of melatonin as an antioxidant exists in the patients with preeclampsia.
Tamura S, Masuda Y, lnokuchi I, Terasawa K, Sugiyama N. Effect of and indication ,for tonsillectomq1 in IgA nephropurhy. Acta Otolaryngol (Stockh) 1993; Suppl 508: 23-28.Although more than 20 years have passed since the initial report of IgA nephropathy, the etiology of this disease is still unclear. Some reports suggest that the tonsil is an important etiological factor. We performed tonsillectomy on 26 patients with IgA nephropathy associated with chronic tonsillitis, and followed up the patients for two years after the operation to evaluate its clinical effect on this disease. Twelve patients (efficacy rate 46%) showed distinct improvement in urinary findings after the operation, although the efficacy rate went down as renal injury advanced. Serum IgA levels decreased significantly after the operation both in patients who improved and in those who did not; the decrease was especially evident in patients who had high levels of serum IgA before tonsillectomy. In 4 patients who improved. the level of circulating immune complex (CIC) was extremely high before, and decreased significantly after. the operation. One patient suffered renal failure three years after tonsillectomy. When renal injury has advanced to the clinically apparent degree, as occurred in this patient, tonsillectomy is absolutely contraindicated. In reaching a decision as to whether tonsillectomy is indicated in mild cases, the change in the number of erythrocytes in urinary sediments may be a sensitive parameter of the tonsillar provocation test. Key worcls: serum IgA, circulating immune comp1e.u. tonsillar protioration test. 583-90, 1984.
These findings suggest that O2- potentiates vascular tension in human umbilical artery, in part, by suppressing NO synthesis in the endothelium. The vasorelaxation by exogenously generated ONOO suggests that this moiety has biological relevance in vasoregulation of the human umbilical artery.
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