Abstract-We showed that the training-induced, pressure-lowering effect correlates with decreased arteriole wall/lumen ratio and venule growth in the gracilis muscle. To investigate whether these beneficial changes are tissue-specific or occur in other muscles and tissues, we analyzed the effects of hypertension and training on microcirculatory profile of locomotor/nonlocomotor muscles and another nonmuscular tissue. Spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats were submitted to low-intensity training (50% to 60% maximal exercise capacity, 13 weeks); age-matched control rats were kept sedentary. Trained and sedentary rats were instrumented for pressure and heart rate measurements at rest. Morphometric analyses (arterioles, capillaries, venules) were performed in all tissues. Training attenuated pressure and heart rate only in SHR. Arterioles (inner diameter Ͻ30 m) were markedly hypertrophied in sedentary SHR, but wall/lumen ratio was equally reduced (Ϸ30%) and normalized by training in locomotor (soleus, gastrocnemius, gracilis) and nonlocomotor skeletal muscles (temporalis) in the myocardium and diaphragm, without changes in the renal cortex. Training also increased venule density (Ϸ2-fold) only in locomotor and nonlocomotor muscles of SHR. Capillary density was similarly increased in all exercised muscles of both groups, with no change in temporalis and kidneys. Data suggest that growth/proliferation of small venules and regression of hypertrophied arteriole wall/lumen ratio are generalized tissue-specific (skeletal muscle) and group-specific (SHR) adjustments to training to reduce local resistance and augment physical capacity of circulation, thus contributing to training-induced pressurelowering effect. They are accompanied by remodeling of myocardium (cardiac output) and diaphragm arterioles (ventilatory adjustments), stressing the importance of training as a nonpharmacological therapy to control pressure levels in hypertension. Key Words: life style Ⅲ hypertension, chronic Ⅲ arterioles Ⅲ capillaries Ⅲ myocardium Ⅲ kidney C hronic hypertension is a highly prevalent disease (affecting 20% of adults and Ϸ50% of elderly) and a common risk factor for different cardiovascular diseases. The search for efficient pharmacological and nonpharmacological antihypertensive therapies is a goal pursued by many researchers and clinicians. 1-3 Experimental evidence has shown that regular physical activity reduces pressure in hypertensive patients, contributing to the decrease cardiovascular morbidity and mortality rates. 3,4 However, very little information on the mechanisms underlying the beneficial effects of repetitive exercise is available.In two recent well-controlled studies on male spontaneously hypertensive rats (SHR), 5,6 we confirmed the efficacy of low-intensity aerobic training to reduce pressure levels, showing in addition that pressure reduction was significantly correlated with both hind limb resistance decrease and normalization of the enlarged arteriole wall-to-lumen ratio, presented by the gr...

Taurine, an important mediator of cellular volume regulation in the central nervous system, is accumulated into neurons and glia by means of a highly specific sodium-dependent membrane transporter. During hyperosmotic cell shrinkage, net cellular taurine content increases as taurine transporter activity is enhanced via elevated gene expression of the transporter protein. In hypo-osmotic conditions, taurine is rapidly lost from cells by means of taurine-conducting membrane channels. We reasoned that changes in taurine transporter activity also might accompany cell swelling to minimize re-accumulation of taurine from the extracellular space. Thus, we determined the kinetic and pharmacological characteristics of neuronal taurine transport and the response to osmotic swelling. Accumulation of radioactive taurine is strongly temperature dependent and occurs via saturable and non-saturable pathways. At concentrations of taurine expected in extracellular fluid in vivo, 98% of taurine accumulation would occur via the saturable pathway. This pathway obeys Michaelis-Menten kinetics with a K m of 30.0 ± 8.8 lM (mean ± SE) and J max of 2.1 ± 0.2 nmol/mg protein min. The saturable pathway is dependent on extracellular sodium with an effective binding constant of 80.0 ± 3.1 mM and a Hill coefficient of 2.1 ± 0.1. This pathway is inhibited by structural analogues of taurine and by the anion channel inhibitors, 4,4¢-diisothiocyanostilbene-2, 2¢-disulfonic acid (DIDS) and 5-nitro-2-(3 phenylpropylamino) benzoic acid (NPPB). NPPB, but not DIDS, also reduces the ATP content of the cell cultures. Osmotic swelling at constant extracellular sodium concentration reduces the J max of the saturable transport pathway by approximately 48%, increases K diff for the non-saturable pathway by 77%, but has no effect on cellular ATP content. These changes in taurine transport occurring in swollen neurons in vivo would contribute to net reduction of taurine content and resulting volume regulation.

Nonsuicidal self-injury (NSSI) is prevalent and affects mainly the youth population. It is prospectively associated with suicide attempts, making it a target for suicide prevention. Recently, several studies have investigated neural pathways of NSSI using neuroimaging. However, there is a lack of systematized appraisal of these findings. This systematic review aims to identify and summarize the main neuroimaging findings of NSSI in youth. We followed PRISMA statement guidelines and searched MEDLINE, APA PsycInfo, and Google Scholar databases for neuroimaging studies, irrespective of imaging modality, specifically investigating NSSI in samples with a mean age of up to 25 years old. Quality assessment was made using the Newcastle–Ottawa and Joanna Briggs Institute scales. The initial search retrieved 3030 articles; 21 met inclusion criteria, with a total of 938 subjects. Eighteen studies employed functional neuroimaging techniques such as resting-state and task-based fMRI (emotional, interpersonal exposure/social exclusion, pain, reward, and cognitive processing paradigms). Three studies reported on structural MRI. An association of NSSI behavior and altered emotional processing in cortico-limbic neurocircuitry was commonly reported. Additionally, alterations in potential circuits involving pain, reward, interpersonal, self-processing, and executive function control processes were identified. NSSI has complex and diverse neural underpinnings. Future longitudinal studies are needed to understand its developmental aspects better.

The use of PRN (as-needed) psychotropic medication in borderline patients has not been well characterized. This study had three purposes: (i) to describe the prevalence of PRN psychotropic medication use among borderline patients and other personality-disordered comparison subjects over 14 years of prospective follow-up; (ii) to examine the rates reported by ever-recovered and never-recovered borderline patients; and (iii) to examine the reasons for taking PRN medication reported by these patients. Overall, the prevalence of PRN psychotropic medication use was initially approximately 3 times higher among borderline patients than other personality-disordered comparison subjects, with a significant one- third decline in the use of PRN medication reported by borderline patients over time. In analyses restricted to borderline patients, never-recovered borderline patients were about twice as likely to use PRN medication than ever-recovered borderline patients over time. In terms of reasons for use, the rates of PRN medication use to decrease agitation for both diagnostic groups declined significantly over time, although they remained significantly higher among borderline patients. Likewise, never-recovered borderline patients reported higher use of PRN medication to decrease agitation than ever-recovered borderline patients over time. The results of this study indicate that PRN psychotropic medication is widely used for the treatment of borderline patients, particularly those who have not achieved a recovery in both the symptomatic and psychosocial realms. They also suggest that borderline patients use proportionally more PRN medication to decrease agitation than other personality comparison subjects, with lower proportional use to reduce agitation found among recovered borderline patients.

No abstract