Bisphenol-A antagonizes the rapidly modulating effect of DHT on spinogenesis and long-term potentiation of hippocampal neurons.

Bisphenol A (BPA), a common environmental endocrine disruptor, modulates estrogenic, antiestrogenic, and antiandrogenic effects throughout the lifespan. Recent studies found more obvious adverse effect of BPA on some neurobehavior in males than that in females. In this study, BPA at 10-100 nM rapidly increased the densities of the dendrite spine and synapse in cultured hippocampal neurons of rats in vitro within 1 h. Co-treatment of BPA (100 nM) with dihydrotestosterone (DHT, 10 nM) or with 17ß-E2 (10 nM) completely eliminated the promotion of DHT or 17ß-E2 in the densities of the dendritic spine and synapse. Pretreatment of estrogen receptors (ERs) antagonist ICI182,780 but not of androgen receptors (ARs) antagonist flutamide (Flu) for 30min completely blocked BPA-enhanced densities of the dendritic spine and synapse. Pretreatment of flutamide for 30min before BPA and DHT completely rescued BPA-enhanced densities of the dendritic spine and synapse. Furthermore, pretreatment of ERK1/2 inhibitor U0126 or p38 inhibitor SB203580 entirely eliminated BPA-induced increases in the densities of the dendritic spine and synapse. Meanwhile, BPA (100 nM) enhanced long-term potentiation (LTP) induction of dentate gyrus in hippocampal slices of younger male rats, which was not blocked by co-incubation of flutamide but was inhibited by pretreatment of an P38 inhibitor SB203580. Co-application of BPA with DHT inhibited DHT-suppressed LTP. These results are the first demonstrating the antagonism of BPA to the rapid modification of DHT in synaptic plasticity. However, BPA alone rapidly promotes spinogenesis and synaptic activity through ER instead of AR, and both ERKs and p38 signaling pathways are involved in these processes.

[Effects on secretory function of rat gonad by Erxian decoction and its disassembled prescriptions].

OBJECTIVE: To explain functions, differences and coordination of three divided combinations of the "Erxian decoction", the famous traditional Chinese formula, on the effective sites of gonad gland at the cell level. METHOD: The effects of Erxian decoction and its main disassembled prescriptions, "Kidney Warming", "Yin Nourishing" and "Chong-ren Adjusting", on the level of testosterone (T) progesterone (P) estradiol (E2), respectively secreted by the primary culture Leydig cell, luteal cell and granulosa cell, were measured by radioimmunoassay. RESULT: (1) Erxian decoction could stimulate the T secretion while its three main disassembled prescriptions would seem no individual promoting effect on the secretion of T. (2) Erxian decoction and the "Kidney Warming" had the stimulating effect on P secretion, and the action of the whole formula being better than that of the "Kidney Warming". (3) Erxian decoction and its main disassembled prescriptions had the stimulating effect on E2 secretion, especially the whole formula. CONCLUSION: Erxian decoction can stimulate the secretion of T of the Leydig cell, P of luteal cell and E2 of granulosa cell. It can be seen that the effect of the whole formula is better than that of its main disassembled prescriptions.