Further acquisitions on gonadal function in bromocriptine treated hyperprolactinemic male patients.

The diurnal variation of plasma total and free testosterone (tT and fT) and the gonadotropinemic response to LH-RH were evaluated in a group of hyperprolactinemic impotent males with pituitary microprolactinoma before and during therapy with bromocriptine, a well known dopamine agonist drug. Before treatment, basal levels not only of tT but also of fT were decreased and the diurnal variation of both tT and fT was absent. Moreover, the LH-RH test showed a delay in the LH response peak, together with normal basal levels of LH. Bromocriptine therapy caused normalization of both the secretion response of LH to LH-RH and of the secretion pattern of tT and of fT (basal levels and diurnal variation) besides a significant decrease in PRL levels and an improvement in sexual function. The possible effects of high plasma levels of PRL at various levels of the hypothalamus-pituitary-testicular axis are discussed.

Comparison of biochemical markers of bone turnover and bone mineral density in different groups of climacteric women.

In the present study we evaluated plasma levels of two markers of bone turnover (osteocalcin (OC) and urinary pyridinium cross-links) in association with bone mineral density (BMI) in different groups of climacteric women. We have investigated 158 women in pre-, peri- and postmenopause. Blood and urine samples for assay of hormones and markers were collected and bone mineral density (BMD) was measured by DEXA densitometry in the distal tenth of the non-dominant forearm. There was a significant increase in mean absolute levels of both markers in perimenopause and women in natural and surgical menopause, with respect to women in premenopause. There was a significant correlation between OC and deoxypyridoline (DPYR) in peri- and postmenopause groups. In peri- and postmenopause groups, BMD was correlated with an increase in the biochemical markers of bone remodeling. In the present study, OC and DPYR were found to have good sensitivity for identifying perimenopausal women with pathological BMD. The present results reveal a positive and significant correlation between DPYR and OC, inversely proportional to BMD, during hormone replacement therapy. These markers therefore turn out to be sensitive not only for monitoring severe pathology of bone turnover, but also for monitoring slight physiological deficits in bone equilibrium beginning in perimenopause.