Angiotensinergic and GABAergic transmission in the medial preoptic area: role in urinary bladder and cardiovascular control in female rats

Introduction: The medial preoptic area (mPOA) participates in thermoregulatory control and blood pressure modulation as shown by studies with electrical stimulation of this or cobalt chloride injection, a non-selective synapse inhibitor. This study aimed to investigate whether angiotensin II (Ang II) GABA could act not the mPOA mediate cardiovascular micturition pathways. Methods: Female Wistar rats were submitted stereotaxic surgery for implantation guide cannula into 7 days prior experiments. Afterwards, animals isoflurane- anesthetized catheterization femoral artery vein urinary bladder cannulation mean arterial (MAP), heart rate (HR), intravesical (IP) recordings, respectively. After baseline MAP, HR, IP recordings 15 min, Ang (0.1 nM, 1 μL), losartan (AT-1 receptor antagonist, 100 (50 mM, μL) saline (1 injected mPOA, variables measured additional 30 min. In different group rats, AT-1 receptor, converting enzyme (ACE), GABAa gene expression was evaluated samples qPCR. data are ± SEM One-way ANOVA (Tukey posttest) paired Student t-test (P <0.05). Results: injection evoked significant hypotension (−37±10 mmHg, n = 6, p 0.024) bradycardia (−47 20 bpm, 0.030) compared (+1 mmHg +6 2 6). A increase observed after (+72.25 17.91%, 0.015 vs. −1.80 2.98%, saline). No changes HR injection. Injection fall MAP (−68 < 0.0001 −115 14 0.0002 −1 +4 saline), but no IP. ACE mRNA all samples. Discussion: Therefore, female mediated transmission is involved regulation central phasic dependent on receptors seems be those 3 parameters. contrast, GABAergic pathways nevertheless, neurotransmission control.