Premenstrual increase of intracellular magnesium levels in women with ovulatory, asymptomatic menstrual cycles.

Intracellular magnesium (Mg) levels regulate several enzymatic reactions and the hypoactivity of Mg has been involved in different pathological states. In addition to other factors, gonadal hormones, too, have been found to interfere in Mg balance. This study evaluates the changes in Mg in women throughout the normal menstrual cycle and those measured at weekly intervals in males. Magnesium and potassium (K) levels were measured in the plasma, red blood cells (RBC), lymphocytes (LC) and polymorphonucleated cells (PMN) of 11 normal menstruating women, in different periods of their menstrual cycle. Blood samples were collected every 4th day. According to the time and LH, progesterone and estradiol levels, they were classed as follicular (Foll), periovulatory (OV), luteal (Lut) or premenstrual (PM). The Menstrual Distress Questionnaire completed by the subjects revealed that no significant symptomatology was present. Four blood samples were also collected from 4 normal males, at weekly intervals. Mg and K were determined by atomic absorption spectrophotometry. LC and PMN were purified by centrifugation on a Ficoll discontinuous gradient. No differences were found in males versus females in the Mg or K contents in the different compartments. In the 4 periods tested, the K levels were constant, in both females and males. The same applies for Mg contents in males. In females, Mg contents, as well as the Mg/K ratio in LC and PMN, showed a significant increase in the premenstrual period compared with the other periods of the cycle. On the contrary, plasma and RBC Mg levels were constant throughout the cycle.