Endocrine Abstracts

The human homeostasis is determined by psycho-neuro-endocrine-immuno processes. This biological balance-system depends on their communication of direct environment (eg. nutrition, respiration, etc. as in the metabolism). The basic of human communication-way with environment are defined by nutrition. This contains various agents: eg. proteins, lipids, sugars, vitamins, ions, etc. When the elements of nutrition is substituted, the markers of homeostatic processes and regulations are needed to follow. In this work our aim was to investigate the AVP mediated neuroendocrine regulation, by sugar (erythritol, saccharin, xylitol, stevia) substitutes. In the experiment Wistar ♂ rats were treated with erythritolin vivo: 0.05 g/500 cm³, saccharin: 2.5 g/500 cm³, xylitol: 0.05 g/500 cm³ and stevia: 0.05 g/500 cm³ for 16 weeks (n = 5/groups). After treating, neurohypophysis were prepared from the Wistar rats for in vitro primer, monolayer cell culture model (NH). The tissues were digested enzymatically (trypsin: 0.2%/Sigma, Germany/for 30 min; collagenase/Sigma, Germany/: 30 µg/cm³ for 40 min; dispase/Sigma, Germany/: 50 µg/cm³ for 40 min in phosphate-buffered saline; temperature: 37°C). Mechanical dissociation was achieved with nylon blutex sieves (Ø: 83 and 48 µm). Cultures were controlled for viability (>95%) by trypan blue tests,after than for function for AVP release (in aspecific and specific regulation). In the research protocol investigation was in NH models: untreated as control, treated with 10^–6 M of dopamine (DA) and/or sulpiridine, and then exposed to erythritol, saccharin, xylitol and stevia, during 120 min. The AVP releases of NH model were measured by radioimmunoassay. The protein content was detected by modified Lowry method. The data were analysed by ANOVA statistical program (n = 6). Our results showed mild modified AVP release activity by different treatments of sugar substitutes. However the AVP release showed expressed changes in the neuroendocrine regulation, when the in vivo sugar supplementation was combined by in vitro DA stimulation. The DA receptor (R_DA) functions were tested by sulpiridine. Our experiments showed that the mechanisms of DA regulated AVP release were supervised by R2_DA. These processes were modulated by erythritol, saccharin, xylitol, stevia. This works was supported by EFOP-3.6.1-16-2016-00008 and EFOP-3.4.3-16-2016-00014, TAMOP-4.2.4.A/2-11/1-2012-0001.