Comparison of 8-weeks of full versus split body resistance training on appetite and energy intake in non-obese untrained men.

To investigate the effects of 8-weeks of full versus split body resistance training (RT) on appetite and energy intake in non-obese untrained men. The participants were pair-matched based on their initial fat mass and then randomly allocated into one of two treatment groups: Full body (FB, n = 20), in which all muscle groups were trained in every session, or Split body (SB, n = 15), in which upper and lower muscle groups were trained alternated per session; both groups trained in non-consecutive days, three times per week with total number of sets performed equated between groups. Energy intake, body composition, and strength performance were evaluated at pre-training, and after 8-weeks of RT, as well as self-reported hunger, fullness, and desire to eat, that were assessed at fasted and feed states pre- and post-intervention. FB and SB resistance training increased fat-free mass (FFM) (p < 0.001); and FB induced greater maximal strength improvement (p = 0.027). At fasted state self-reported hunger increased, and fullness decreased, while in feed state desire to eat something fatty increased in both groups. Carbohydrate intake (p = 0.011) decreased in both groups. In conclusion, FB and SB training increased orexigenic drive (increasing hunger and decreasing fullness), however, total energy intake and fat mass did not change after 8-weeks of RT in non-obese untrained men.Registered under Brazilian Registry of Clinical Trials no. RBR-3wkcvyw.

Role of hydrogen sulfide in ventilatory responses to hypercapnia in the medullary raphe of adult rats.

NEW FINDINGS: What is the central question of this study? There is evidence that H2 S plays a role in the control of breathing: what are its actions on the ventilatory and thermoregulatory responses to hypercapnia via effects in the medullary raphe, a brainstem region that participates in the ventilatory adjustments to hypercapnia? What is the main finding and its importance? Hypercapnia increased the endogenous production of H2 S in the medullary raphe. Inhibition of endogenous H2 S attenuated the ventilatory response to hypercapnia in unanaesthetized rats, suggesting its excitatory action via the cystathionine ß-synthase-H2 S pathway in the medullary raphe. ABSTRACT: Hydrogen sulfide (H2 S) has been recently recognized as a gasotransmitter alongside carbon monoxide (CO) and nitric oxide (NO). H2 S seems to modulate the ventilatory and thermoregulatory responses to hypoxia and hypercapnia. However, the action of the H2 S in the medullary raphe (MR) on the ventilatory responses to hypercapnia remains to be elucidated. The present study aimed to assess the role of H2 S in the MR (a brainstem region that contains CO2 -sensitive cells and participates in the ventilatory adjustments to hypercapnia) in the ventilatory responses to hypercapnia in adult unanaesthetized Wistar rats. To do so, aminooxyacetic acid (AOA; a cystathionine ß-synthase (CBS) enzyme inhibitor), propargylglycine (PAG; a cystathionine γ-lyase enzyme inhibitor) and sodium sulfide (Na2 S; an H2 S donor) were microinjected into the MR. Respiratory frequency (fR ), tidal volume (VT ), ventilation ( V̇E ), oxygen consumption ( V̇O2 ) and body temperature (Tb ) were measured under normocapnic (room air) and hypercapnic (7% CO2 ) conditions. H2 S concentration within the MR was determined. Microinjection of the drugs did not affect fR , VT and V̇E during normocapnia when compared to the control group. However, the microinjection of AOA, but not PAG, attenuated fR and V̇E during hypercapnia in comparison to the vehicle group, but had no effects on Tb . In addition, we observed an increase in the endogenous production of H2 S in the MR during hypercapnia. Our findings indicate that endogenously produced H2 S in the MR plays an excitatory role in the ventilatory response to hypercapnia, acting through the CBS-H2 S pathway.

Cigarette smoke exposure causes systemic and autonomic cardiocirculatory changes in rats depending on the daily exposure dose.

AIMS: To evaluate the systemic changes and autonomic cardiocirculatory control of awaken rats chronically exposed to the cigarette smoke (CS) of 1 or 2 cigarettes/day. MAIN METHODS: Rats were exposed to clean air (control) or cigarette smoke of 1 (CS1) or 2 (CS2) cigarettes/animal/day for 30 days. Then, arterial pressure (AP) and heart rate (HR) were recorded in conscious rats to assess spontaneous baroreflex sensitivity and HR and AP variabilities. Evoked baroreflex and cardiac autonomic tone were evaluated by vasoactive drugs and autonomic blockers, respectively. In another group, ventilatory and cardiovascular parameters were recorded under hypoxia and hypercapnia stimulus. At the end of protocols, heart, lung, kidneys and liver were collected for histological analysis. KEY FINDINGS: Rats exposed to CS showed morphological changes, being more evident in the CS2 group. Also, less weight gain and cardiac hypertrophy were prominent in CS2 rats. Basal AP and HR, spontaneous baroreflex sensitivity and cardiovascular variabilities were similar among groups. CS exposure progressively blunted the bradycardia response to phenylephrine (-2.2 ± 0.1 vs. -1.7 ± 0.2 vs. -1.5 ± 0.2) while the tachycardia response to sodium nitroprusside was slightly increased compared to control. Vagal tone was not affected by CS, but CS2 rats exhibited higher sympathetic tone (-25 ± 4 vs. -28 ± 4 vs. -56 ± 9) and lower intrinsic HR (411 ± 4 vs. 420 ± 8 vs. 390 ± 6). Exposure to CS of 2 cigarettes also exacerbated the reflex cardiovascular and ventilatory responses to hypoxia and hypercapnia. SIGNIFICANCE: CS exposure for 30 days promoted systemic changes and autonomic cardiocirculatory dysfunction in rats depending on the daily exposure dose.

Exercise and pyridostigmine prevents gastric emptying delay and increase blood pressure and cisplatin-induced baroreflex sensitivity in rats.

Cisplatin treatment induces an autonomic dysfunction and gastrointestinal and cardiovascular disorders. Physical exercise as well as pyridostigmine treatment induces improves in the autonomic nervous system. In the current study, we investigated the effect of physical exercise and pyridostigmine treatment on gastrointestinal and cardiovascular changes in cisplatin-treated rats. Rats were divided into groups: Saline (S), Cisplatin (Cis), Exercise (Ex), Cisplatin+Exercise (Cis+Ex), Pyridostigmine (Pyr), and Cisplatin+Pyridostigmine (Cis+Pyr). We induced gastrointestinal dysmotility by administering 3 mg kg-1 of cisplatin once week for 5 weeks. The Ex was swimming (1 h per day/5 days per week for 5 weeks with 5% b.w.). GE was evaluated through the colorimetric method of fractional red phenol recovery 10 min after feeding. Pyr groups received 1.5 mg kg-1, p.o. or concomitant Cis treatment. Moreover, gastric contraction in vitro and hemodynamic parameters such as MAP, HR, and evoked baroreflex sensitivity were assessed, as well as sympathetic and parasympathetic tone and intrinsic heart rate (IHR). Cis decrease GE vs. saline (p<0.05). Cis+Ex or Cis+Pyr prevented (p<0.05) decrease in GE vs. Cis rats. Cis decreased (p<0.05) gastric responsiveness in vitro vs. saline. Cis+Ex or Cis+Pyr prevented this phenomenon. Cis treatment increase MAP and decrease in HR (p<0.05) vs saline. Cis+Ex or Cis+Pyr attenuated (p<0.05) both alterations. Cis increased sympathetic tone and decreased vagal tone and IHR (p<0.05) vs. the saline. Cis+Ex or Cis+Pyr prevented those effects vs. the Cis group. In conclusion, physical exercise and pyridostigmine treatment improves autonomic dysfunction and prevented GE delay and changes in hemodynamic parameters, baroreflex sensitivity, and cardiac autonomic control in cisplatin-treated rats.

Acetylcholinesterase inhibition prevents alterations in cardiovascular autonomic control and gastric motility in L-NAME-induced hypertensive rats.

AIMS: Autonomic dysfunction in arterial hypertension affects cardiorespiratory control and gastric motility and has been characterized by increased sympathetic and reduced parasympathetic activity. In the present work we investigated the effects of anticholinesterase drugs [donepezil (DON) or pyridostigmine (PYR)] on cardiovascular, autonomic, and gastric parameters in L-NAME-induced hypertensive rats. MATERIALS AND METHODS: Daily oral gavage of L-NAME (70 mg/kg/day) was performed over 14 days in male Wistar rats (180-220 g), whereas daily oral gavage of DON or PYR (1.6 and 22 mg/kg/day, respectively) started 2 days after the L-NAME treatment initiation and lasted 12 days. The development of hypertension was verified by tail plethysmography technique. After the end of treatments, the animals were subjected to experimental protocols (6-12 animals per group; total number of animals used: 78). KEY FINDINGS: L-NAME hypertensive animals had no alterations in heart rate (HR) and intrinsic HR, but showed reduction in baroreflex sensitivity, parasympathetic tone, and gastric motility; and the sympathetic tone, chemoreflex sensitivity, and the LF (low frequency) band of systolic arterial pressure (SAP) variability were increased. DON or PYR attenuated the increase in mean arterial pressure (MAP) induced by L-NAME. Both anticholinesterase drugs were effective in preventing the decrease in baroreflex sensitivity, parasympathetic tone and gastric motility, and also prevented the increases in peripheral chemoreflex response and cardiac sympathetic tone. SIGNIFICANCE: Acetylcholinesterase inhibition with DON or PYR is a promising pharmacological approach to increase parasympathetic function, thus preventing the hypertension-induced alterations in the cardiovascular, gastrointestinal and autonomic systems.