Diabetes augments the risk of hypertension. Although several factors have been implicated in the development of such hypertensive state, we designed this study to investigate blood pressure development, the activity of angiotensin-converting enzyme (ACE) in blood as well as sympathetic neurotransmission in the vas deferens of diabetic rats. We used streptozotocin (STZ)-induced diabetic rats (60 mg/kg) in order to evaluate the systolic blood pressure (SBP), ACE activity and peripheral sympathetic neurotransmission. We observed the following changes of parameters: increase of SBP, decrease of heart rate, augmentation of plasma ACE activity, enhancement of phasic and tonic vas deferens contractions elicited by electrical stimulation at 5 Hz, increase of maximal response to noradrenaline (NA) and decrease of adenosine triphosphate (ATP)-elicited contraction of vasa deferentia. The results reveal that in the development of hypertension in diabetic rats, augmentation of circulating ACE activity precedes the sympathetic dysfunction. Additionally, it seems that the purinergic and noradrenergic neurotransmission is compromised.

Hypertension and diabetes development had been characterized as idiopathic disorders tightly interconnected, and therefore it is essential to understand how the functionality of neurohormonal pathways are involved in both diseases. Hypertensive and diabetic patients have shown increased systolic blood pressure (SBP), oxidative stress, vascular hypertrophy, and remodeling. It is well established that the long-term consumption of red wine and/or polyphenol-stilbene causes cardioprotective and antihypertensive effects; however, some functions remain unrevealed. Downstream pathways such as reactive oxygen species (ROS), sympathoadrenal axis represented by β₁-adrenoceptors, and renin–angiotensin system via angiotensin-II receptors critically contribute to hypertension development.

Objectives: Angiotensin I-converting enzyme (ACE) was initially correlated with SCZ in studies showing a correlation of ACE increased enzyme activity with memory impairments. Possible role for ACE in SCZ was also suggested by ACE activity interaction with dopaminergic mechanisms to modulate abnormalities of sensorimotor gating. In addition, we have demonstrated higher ACE activity in blood of SCZ subjects, ACE activity implication in cognitive performance in SCZ and its power as predictor for SCZ diagnosis. Methods: ACE activity was determined in the serum and in selected brain regions of an animal model presenting SCZ-like behavior, before and after the treatment with typical and atypical antipsychotics, and also in the serum of animals receiving the psychostimulants amphetamine/lisdexamphetamine. Results: Dopaminergic manipulations with antipsychotics and psychostimulants influenced the ACE activity, but with no correlation with the animal blood pressure. Conclusions: The validity of measuring the ACE activity in animal blood to predict the activity in CNS, as well as the lack of correlation between the activity and blood pressure, before and after the treatment with antipsychotics, were confirmed here. Correlations of the present findings with data from clinical studies also strengthen the value of this animal model for studying several aspects of SCZ.

It is known that red wine has cardioprotective properties. However, its influence is unknown about purinergic system. Therefore, we study the influence of the treatment with red wine or ethanol in purinergic neurotransmission. We used Wistar Kyoto rats (WKY), diabetic streptozotocin-induced WKY and spontaneously hypertensive rats (SHR), treated with red wine (12.5%) or ethanol (12.5%). The cardiovascular function stimulated with purinergic agonists and systolic blood pressure (SBP) was assessed. In atria of diabetics and SHRs, the P1 receptor response was decreased, unlike the P2 receptor response was increased. Likewise, in aorta the affinity to adenosine (ADO) was decreased from SHRs and diabetics. Furthermore, the P2X function was increased just SHRs. All these alterations were improved after treatment with red wine, resulting in reduction of SBP from diabetics and SHRs, but not when treated with ethanol. This study has important implications, because it is shown that consumption of red wine can improve cardiovascular system by purinergic neurotransmission.