Role of tactile stimulation during the preweaning period on the development of the peripheral sensory sural (SU) nerve in adult artificially reared female rat.

Maternal deprivation, as a result of the artificial rearing (AR) paradigm, disturbs electrophysiological and histological characteristics of the peripheral sensory sural (SU) nerve of infant and adult male rats. Such changes are prevented by providing tactile or social stimulation during isolation. AR also affects the female rat's brain and behavior; however, it is unknown whether this early adverse experience also alters their SU nerve development or if tactile stimulation might prevent these possible developmental effects. To assess these possibilities, the electrophysiological and histological characteristics of the SU nerve from adult diestrus AR female rats that: (i) received no tactile stimulation (AR group), (ii) received tactile stimulation in the anogenital and body area (AR-Tactile group), or (iii) were mother reared (MR group) were determined. We found that the amplitude, but not the area, of the evoked compound action potential response in SU nerves of AR rats was lower than those of SU nerves of MR female rats. Tactile stimulation prevented these effects. Additionally, we found a reduction in the outer diameter and myelin thickness of axons, as well as a large proportion of axons with low myelin thickness in nerves of AR rats compared to the nerves of the MR and AR-Tactile groups of rats; however, tactile stimulation only partially prevented these effects. Our data indicate that maternal deprivation disturbs the development of sensory SU nerves in female rats, whereas tactile stimulation partially prevents the changes generated by AR. Considering that our previous studies have shown more severe effects of AR on male SU nerve development, we suggest that sex-associated factors may be involved in these processes.

Mother and sibling interactions during the preweaning period influence myelination and impulse propagation of the sensory sural nerve in the adult rat.

To investigate whether mother and sibling interactions during the preweaning period influence the histological and electrophysiological characteristics of the sensory sural nerve (SUn) in the adult rat, litters composed of 1, 3, 6, 9, and 12 male pups (P) were formed and the pups routinely weighed until postnatal day 60 (PND60). At PND9, 3P and 6P litters showed greater body weight than pups without siblings or from 9P or 12P litters, and such differences in weight were maintained until adulthood. Analysis of maternal licking at PND8 and 9 showed that pups from large litters received fewer licks than pups from small size litters. At PND60, SUn of rats from 6P and 9P litters had greater compound action potential (CAP) amplitude and a higher proportion of axons with large myelin thickness than nerves from rats of 1P, 3P, or 12P litters. SUn of heaviest rats from 9P and 12P litters had greater CAP area and myelination than the lightest rats from the same litters. We propose that a complex interplay of sensory, social, and nutritional factors arising from mother and littermate interactions during the preweaning period influence myelination and the propagation of action potentials in the SUn of adult rats.

Day-Night Variations in the Concentration of Neurotransmitters in the Rat Lumbar Spinal Cord.

The purpose of this study was to analyze the light-dark variations in the concentrations of several neurotransmitters in the lumbar spinal cord of rats. Six groups of male Wistar rats were exposed to a 12 h light-12 h dark cycle for 70 days. At different time points of the experimental day (8, 12, 16, 20, 24 and 4 h), one of the groups of rats was randomly selected to be sacrificed, and the spinal cords were removed. The gamma-aminobutyric acid (GABA), glutamate (GLU), dopamine, serotonin, epinephrine (E), and norepinephrine (NE) levels in each extracted spinal cord were measured with high-pressure liquid chromatography (HPLC)-EQ and HPLC-fluorescence systems. Our results indicate that the spinal concentrations of GABA and GLU showed sinusoidal variation in a 24 h cycle, with the highest peak in the dark period (~20 h). Dopamine and serotonin also fluctuated in concentration but peaked in the light period (between 8 and 12 h), while E and NE concentrations showed no significant fluctuations. The possible relationship between neurotransmitter spinal concentration and sensitivity to pain and locomotor activity is discussed. It was concluded that most of the neurotransmitter levels in the lumbar spinal cord showed circadian fluctuations coupled to a light-dark cycle.

Multiparity modifies contractile properties of pelvic muscles affecting the genesis of vaginal pressure in rabbits.

AIMS: To characterize the contractile properties of the bulbospongiosus (Bsm), isquiocavernosus (Ism), and pubococcygeus muscles (Pcm), and their involvement in the genesis of vaginal pressure in nulliparous and multiparous rabbits. METHODS: Age-matched nulliparous and multiparous rabbits were used to record the isometric contractile responses of each muscle as well as the intravaginal pressure evoked by single square electrical pulses and stimulation trains of ascending frequency. To establish significant differences between groups, two-tail unpaired Student t tests were carried out. The linear correlation between intravaginal pressure and muscle contractile force was analyzed with Pearson correlation tests. For all cases, a P ≤ 0.05 was set as statistically significant. RESULTS: Multiparity decreased the contractile force of Bsm and Ism generated by high-frequency stimulation trains. The normalized force of the Pcm increased when evoked at 1, 4, and 10 Hz while this decreased at higher frequencies (20, 50, and 100 Hz). The contraction of both Bsm and Ism raised particularly the pressure on the perineal vagina while that of the Pcm increased the pressure in the pelvic vagina. Such a functional segregation is still present in multiparous rabbits albeit it was modified. CONCLUSIONS: Multiparity induces changes in the contractile responses of Bsm, Ism, and Pcm, which alterates the vaginal pressure.

Oxytocin, a main breastfeeding hormone, prevents hypertension acquired in utero: A therapeutics preview.

Hypertension is a major risk factor for ischemic heart disease and stroke, leading causes of morbidity and death worldwide. Intrauterine growth restriction (IUGR), caused by an excess of glucocorticoid exposure to the fetus, produces an imbalance in oxidative stress altering many biochemical and epigenetic gene transcription processes exposing the fetus and neonate to the 'thrifty' phenotype and pervasive polymorphisms appearance damaging health, cognitive, and behavioral processes in later life. OT is a major regulator of oxidative stress radicals that plays a major role in neonatal maturation of the central nervous system and many peripheral tissues expressing oxytocin/oxytocin-receptor (OT/OTR) system in the early postnatal period. OT and OTR are damaged by IUGR and early stress. This review highlights the fact that hypertension is likely to be a legacy of preterm birth due to IUGR and failure to meet nutritional needs in early infancy when fed formula instead of breastfeeding or human milk.

Fiber type composition of pubococcygeus and bulbospongiosus striated muscles is modified by multiparity in the rabbit.

AIMS: We analyzed the effect of multiparity on the fiber type composition of two skeletal muscles involved in the maintenance of the micturition process, the pelvic pubococcygeus (Pc) and perineal bulbospongiosus (Bs) muscles in nulliparous and multiparous rabbits (Oryctolagus cuniculus). METHODS: We used the basic ATPase and NADH-TR techniques to identify and characterize slow, intermediate, and fast fiber types and glycolitic and oxidative fibers in muscles, respectively. RESULTS: Pc muscles of multiparous rabbits present relatively high percentages of slow and intermediate fibers but a low percentage of fast fibers (P < 0.05) as compared to Pc muscles from nulliparous rabbits, while percentages of glycolytic and oxidative fibers were similar (P > 0.05). Bs muscles of multiparous rabbits had a higher proportion of intermediate and glycolytic fibers (P < 0.05) than muscles of nulliparous. Both, Pc and Bs muscles of nulliparous and multiparous rabbits contain slow fibers with similar large cross sectional area, but fast fibers in multiparous muscles showed small cross sectional area than in nulliparous. CONCLUSIONS: Multiparity modified the fiber type composition of Pc and Bs muscles in female rabbits. We propose that the contractile force and the physiological role of both muscles during micturition are affected because of the observed changes in the relative composition of muscle fiber types.

Depressing effect of electroacupuncture on the spinal non-painful sensory input of the rat.

The aim of this study was to explore the effect of electroacupuncture (EA) applied in the Zusanli (ST36) and Sanyinjiao (SP6) points on the N1 component of the cord dorsum potential (CDP) evoked by electrical stimulation of the sural nerve (SU) in the rat. The experiments were performed in 44 Wistar rats (250-300 g) anesthetized with ketamine (100 mg/kg) and xylazine (2 mg/kg). A bilateral laminectomy was performed to expose the L3 to S2 segments of the spinal cord. The SU nerve was exposed and placed on pairs of hook electrodes for electrical stimulation. The N1-CDPs were recorded with three silver-ball electrodes located on the dorsal surface of the L5 to S1 segments. Ipsilateral high and low EA stimulation (100, 2 Hz, 6 mA, 30 min) induced a considerable reduction in the amplitude (45 ± 5.6, 41 ± 6.2%) of the N1-CDP recorded at the L6 segmental level. Recovery of the N1-CDP amplitude occurred approximately 1-3 s after EA. Sectioning of the saphenous and superficial peroneal nerves reduced the depressing effect provoked by the EA stimulation (18.7 ± 1.3, 27 ± 3.8%). Similarly, sectioning of the posterior and anterior tibial, deep peroneal and gastrocnemius nerves partially reduced the effect provoked by EA (11 ± 1.5, 9.8 ± 1.1, 12.6 ± 1.9%). Intravenous picrotoxin (1 mg/kg) also reduced the action of low and high EA (23 ± 4.8, 27 ± 5.2%). It is suggested that EA stimulation depresses non-painful sensory pathways through the activation of specific inhibitory pathways that receive modulatory actions from other sensory and muscle afferent inputs in the rat spinal cord.

Influence of chronic food deprivation on structure-function relationship of juvenile rat fast muscles.

In the present study, we analyze the influence of chronic undernutrition on protein expression, muscle fiber type composition, and fatigue resistance of the fast extensor digitorum longus (EDL) muscle of male juvenile rats (45 ± 3 days of life; n = 25 and 31 rats for control and undernourished groups, respectively). Using 2D gel electrophoresis and mass spectrometry, we identified in undernourished muscles 12 proteins up-regulated (8 proteins of the electron transport chain and the glycolytic pathway, 2 cross-bridge proteins, chaperone and signaling proteins that are related to the stress response). In contrast, one down-regulated protein related to the fast muscle contractile system and two other proteins with no changes in expression were used as charge controls. By means of COX and alkaline ATPase histochemical techniques and low-frequency fatigue protocols we determined that undernourished muscles showed a larger proportion (15% increase) of Type IIa/IId fibers (oxidative-glycolytic) at the expense of Type IIb (glycolytic) fibers (15.5% decrease) and increased fatigue resistance (55.3%). In addition, all fiber types showed a significant reduction in their cross-sectional area (slow: 64.4%; intermediate: 63.9% and fast: 61.2%). These results indicate that undernourished EDL muscles exhibit an increased expression of energy metabolic and myofibrillar proteins which are associated with the predominance of oxidative and Type IIa/IId fibers and to a higher resistance to fatigue. We propose that such alterations may act as protective and/or adaptive mechanisms that counterbalance the effect of chronic undernourishment.

Endogenous content and release of [(3)H]-GABA and [(3)H]-glutamate in the spinal cord of chronically undernourished rat.

The aim of this study was to determine the effect of chronic undernutrition on the content and release of γ-amino butyric acid (GABA) and glutamate (GLU) transmitters in the rat spinal cord. The release of [(3)H]-GABA and [(3)H]-GLU was determined by radioactive liquid scintillation techniques, and the concentrations of GABA and GLU in spinal cord preparations from control and undernourished young rats (50-60 days old) were measured by reverse-phase HPLC. The GABA and GLU contents in the lumbar spinal dorsal horn (L6 segment) were significantly lower in undernourished rats relative to control rats (22.2 ± 3.7 and 10.7 ± 1.9 %, respectively; P < 0.05). Spinal cord blocks from undernourished animals also showed lower rates of [(3)H]-GABA and [(3)H]-GLU release than controls (27.6 ± 3.5 and 12.8 ± 2.5 %, respectively; P < 0.01). We propose that the decreases in GLU content and release are consistent with a reduced activation of either afferent fibers, spinal glutaminergic neurons, or both. Furthermore, we propose that the decreased content and release of GABA in undernourished animals are related to a depression in pre- and post-synaptic inhibition. In addition, we hypothesize that the reductions in GABA content and release serve as compensatory mechanisms to counterbalance decreases in sensory transmission and GLU content in the spinal cord of the chronically undernourished rat.

Locomotion Outcome Improvement in Mice with Glioblastoma Multiforme after Treatment with Anastrozole.

Glioblastoma Multiforme (GBM) is a tumor that infiltrates several brain structures. GBM is associated with abnormal motor activities resulting in impaired mobility, producing a loss of functional motor independence. We used a GBM xenograft implanted in the striatum to analyze the changes in Y (vertical) and X (horizontal) axis displacement of the metatarsus, ankle, and knee. We analyzed the steps dissimilarity factor between control and GBM mice with and without anastrozole. The body weight of the untreated animals decreased compared to treated mice. Anastrozole reduced the malignant cells and decreased GPR30 and ERα receptor expression. In addition, we observed a partial recovery in metatarsus and knee joint displacement (dissimilarity factor). The vertical axis displacement of the GBM+anastrozole group showed a difference in the right metatarsus, right knee, and left ankle compared to the GBM group. In the horizontal axis displacement of the right metatarsus, ankle, and knee, the GBM+anastrozole group exhibited a difference at the last third of the step cycle compared to the GBM group. Thus, anastrozole partially modified joint displacement. The dissimilarity factor and the vertical and horizontal displacements study will be of interest in GBM patients with locomotion alterations. Hindlimb displacement and gait locomotion analysis could be a valuable methodological tool in experimental and clinical studies to help diagnose locomotive deficits related to GBM.

Metal ion content of internal organs in the calorically restricted Wistar rat.

BACKGROUND: Despite the agreed principle that access to food is a human right, undernourishment and metal ion deficiencies are public health problems worldwide, exacerbated in impoverished or war-affected areas. It is known that maternal malnutrition causes growth retardation and affects behavioral and cognitive development of the newborn. Here we ask whether severe caloric restriction leads per se to disrupted metal accumulation in different organs of the Wistar rat. METHODS: Inductively coupled plasma optical emission spectroscopy was used to determine the concentration of multiple elements in the small and large intestine, heart, lung, liver, kidney, pancreas, spleen, brain, spinal cord, and three skeletal muscles from control and calorically restricted Wistar rats. The caloric restriction protocol was initiated from the mothers prior to mating and continued throughout gestation, lactation, and post-weaning up to sixty days of age. RESULTS: Both sexes were analyzed but dimorphism was rare. The pancreas was the most affected organ presenting a higher concentration of all the elements analyzed. Copper concentration decreased in the kidney and increased in the liver. Each skeletal muscle responded to the treatment differentially: Extensor Digitorum Longus accumulated calcium and manganese, gastrocnemius decreased copper and manganese, whereas soleus decreased iron concentrations. Differences were also observed in the concentration of elements between organs independently of treatment: The soleus muscle presents a higher concentration of Zn compared to the other muscles and the rest of the organs. Notably, the spinal cord showed large accumulations of calcium and half the concentration of zinc compared to brain. X-ray fluorescence imaging suggests that the extra calcium is attributable to the presence of ossifications whereas the latter finding is attributable to the low abundance of zinc synapses in the spinal cord. CONCLUSION: Severe caloric restriction did not lead to systemic metal deficiencies but caused instead specific metal responses in few organs.

Hypothalamic A11 Nuclei Regulate the Circadian Rhythm of Spinal Mechanonociception through Dopamine Receptors and Clock Gene Expression.

Several types of sensory perception have circadian rhythms. The spinal cord can be considered a center for controlling circadian rhythms by changing clock gene expression. However, to date, it is not known if mechanonociception itself has a circadian rhythm. The hypothalamic A11 area represents the primary source of dopamine (DA) in the spinal cord and has been found to be involved in clock gene expression and circadian rhythmicity. Here, we investigate if the paw withdrawal threshold (PWT) has a circadian rhythm, as well as the role of the dopaminergic A11 nucleus, DA, and DA receptors (DR) in the PWT circadian rhythm and if they modify clock gene expression in the lumbar spinal cord. Naïve rats showed a circadian rhythm of the PWT of almost 24 h, beginning during the night-day interphase and peaking at 14.63 h. Similarly, DA and DOPAC's spinal contents increased at dusk and reached their maximum contents at noon. The injection of 6-hydroxydopamine (6-OHDA) into the A11 nucleus completely abolished the circadian rhythm of the PWT, reduced DA tissue content in the lumbar spinal cord, and induced tactile allodynia. Likewise, the repeated intrathecal administration of D1-like and D2-like DA receptor antagonists blunted the circadian rhythm of PWT. 6-OHDA reduced the expression of Clock and Per1 and increased Per2 gene expression during the day. In contrast, 6-OHDA diminished Clock, Bmal, Per1, Per2, Per3, Cry1, and Cry2 at night. The repeated intrathecal administration of the D1-like antagonist (SCH-23390) reduced clock genes throughout the day (Clock and Per2) and throughout the night (Clock, Per2 and Cry1), whereas it increased Bmal and Per1 throughout the day. In contrast, the intrathecal injection of the D2 receptor antagonists (L-741,626) increased the clock genes Bmal, Per2, and Per3 and decreased Per1 throughout the day. This study provides evidence that the circadian rhythm of the PWT results from the descending dopaminergic modulation of spinal clock genes induced by the differential activation of spinal DR.

Growth performance, carcass traits, muscle fiber characteristics and skeletal muscle mRNA abundance in hair lambs supplemented with ferulic acid.

Ferulic acid (FA) is a phytochemical with various bioactive properties. It has recently been proposed that due to its phytogenic action it can be used as an alternative growth promoter additive to synthetic compounds. The objective of the present study was to evaluate the growth performance, carcass traits, fiber characterization and skeletal muscle gene expression on hair-lambs supplemented with two doses of FA. Thirty-two male lambs (n = 8 per treatment) were individually housed during a 32 d feeding trial to evaluate the effect of FA (300 and 600 mg d-1) or zilpaterol hydrochloride (ZH; 6 mg d-1) on growth performance, and then slaughtered to evaluate the effects on carcass traits, and muscle fibers morphometry from Longissimus thoracis (LT) and mRNA abundance of ß2-adrenergic receptor (ß2-AR), MHC-I, MHC-IIX and IGF-I genes. FA increased final weight and average daily gain with respect to non-supplemented animals (p < 0.05). The ZH supplementation increased LT muscle area, with respect to FA doses and control (p < 0.05). Cross-sectional area (CSA) of oxidative fibers was larger with FA doses and ZH (p < 0.05). Feeding ZH increased mRNA abundance for ß2-AR compared to FA and control (p < 0.05), and expression of MHC-I was affected by FA doses and ZH (p < 0.05). Overall, FA supplementation of male hair lambs enhanced productive variables due to skeletal muscle hypertrophy caused by MHC-I up-regulation. Results suggest that FA has the potential like a growth promoter in lambs.

Heart Rate Variability and Psychometric Analysis in Patients with Hyperactive Heart Fire Syndrome.

Background: Hyperactive heart fire syndrome is characterized by anxiety, insomnia, dream-disturbed sleep, tongue ulcers, heat in the hands, and palpitations. However, syndrome differentiation is often subjective due to a lack of objective, quantifiable variables. Objectives: To identify changes in heart rate variability (HRV) and psychometric analysis in patients with hyperactive heart fire syndrome. Methods: Healthy controls (n = 33) were compared to patients with hyperactive heart fire syndrome (n = 48) from the Integrative University Clinic of the State University of Ecatepec Valley (CIU-UNEVE). Physiological outcome measures included heart rate (HR), the standard deviation of the normal-to-normal heartbeat intervals (SDNN), low (LF) and high frequency (HF) power, and the LF/HF ratio. Psychometric outcome measures included the Athens Insomnia Scale (AIS) and the Hamilton Anxiety Rating Scale (HARS). Results: Compared to controls, hyperactive heart fire patients had higher HR (9.6 ± 2.62%), LF (22 ± 4.21%) and LF/HF ratio (23 ± 3.14%), and lower SDNN (21 ± 2.33%) and HF (18 ± 4.61%). Patients showed increased anxiety, both with somatic (33 ± 11.2%) and psychic symptoms (39 ± 10.5%) with more difficulty falling asleep (47 ± 9.9%) and diurnal impact of sleep (31 ± 9.6%). Conclusion: Hyperactive heart fire patients may have a sympathovagal imbalance due to a reduced parasympathetic tone and/or adominant sympathetic tone, which may be at the origin of the observed symptoms of insomnia and anxiety.

Effects of Ferulic Acid Supplementation on Growth Performance, Carcass Traits and Histochemical Characteristics of Muscle Fibers in Finishing Pigs.

FA dietary supplementation on the growth performance, carcass traits and histochemical characteristics of the Longissimus thoracis muscle from finishing pigs was investigated. Four hundred and twenty pigs were used in this study, and 105 animals (with five replicate pens and 21 pigs per pen) were assigned to one of four treatments: basal diet (BD) without additives (C-); BD + 10 ppm ractopamine hydrochloride + 0.97% lysine (C+); BD + 25 ppm of FA (FA); and BD + 25 ppm of FA + 0.97% lysine (FA-Lys). Dietary supplementation with FA or ractopamine increased both the average daily gain (14%) and loin muscle area (19%), while fat deposition decreased by 53%, in comparison with C- (p < 0.05). The growth performance of pigs treated with FA was similar to those of ractopamine (p > 0.05). The histochemical analysis showed that FA and C+ treatments induced a shift in muscle fiber types: from fast fibers to intermediate (alkaline ATPase) and from oxidative to glycolytic fibers. Muscle tissues from animals treated with FA or ractopamine had a lower cross-sectional area and a greater number of muscle fibers per area (p < 0.05). Findings regarding growth performance and carcass traits indicate that FA supplementation at 25 ppm without extra-lysine can replace the use of ractopamine as a growth promoter in finishing pigs.

Epicatechin treatment generates resilience to chronic mild stress-induced depression in a murine model.

Several studies have proposed that cocoa products-enriched in flavonoids reduce anxiety and depressive symptoms. (-)-Epicatechin (Epi), a flavonoid present in high concentration in cocoa, has been associated with many dark chocolate effects and has been postulated as an exercise mimetic. Physical exercise is used as an adjuvant treatment for many depressive patients. This study aimed to evaluate the impact of Epi on resilience in depression-like behavior in a murine model. Male mice were randomly selected and divided into four groups (n = 8/group). Beginning at the age of 8-9 weeks, the mice were subjected to Chronic Mild Stress (CMS) and/or treatment Epi for five weeks. Epi was administered by oral gavage twice daily/5 weeks. The control group was housed in conditions without stress and Epi treatment. Depressive behavior was evaluated by sucrose preference and open field tests. Interestingly, Epi reduced anhedonia and anxiogenic behavior in the murine stress model. These results suggest that Epi induces resilience to stress-induced depression. Furthermore, our findings propose that muscles respond to Epi treatment according to their type of metabolism and that kynurenine aminotransferases (KATs) could play a role in modulating this response.

Chronic Undernutrition Differentially Changes Muscle Fiber Types Organization and Distribution in the EDL Muscle Fascicles.

Fiber type composition, organization, and distribution are key elements in muscle functioning. These properties can be modified by intrinsic and/or extrinsic factors, such as undernutrition and injuries. Currently, there is no methodology to quantitatively analyze such modifications. On one hand, we propose a fractal approach to determine fiber type organization, using the fractal correlation method in software Fractalyse. On the other hand, we applied the kernel methodology from machine learning to build radial-basis functions for the spatial distribution of fibers (distribution functions), by dividing into square cells a two-dimensional binary image for the spatial distribution of fibers from a muscle fascicle and mounting on each cell a radial-basis function in such a way that the sum of all cell functions creates a smooth version of the fiber histogram on the cell grid. The distribution functions thus created belong in a reproducing kernel Hilbert space which permits us to regard them as vectors and measure distances and angles between them. In the present study, we analyze fiber type organization and distribution in fascicles (F2, F3, F4, and F5) of the extensor digitorum longus muscle (EDLm) from control and undernourished male rats. Fibers were classified according to the ATPase activity in slow, intermediate, and fast. Then, (x, y) coordinates of fibers were used to build binary images and distribution functions for each fiber type and both conditions. The fractal organization analysis showed that fast and intermediate fibers, from both groups, had a fractal organization within the four fascicles, i.e., the fiber assembly is distributed in clusters. We also show that chronic undernutrition altered the organization of fast fibers in the F3, although it still is considered a fractal organization. Distribution function analysis showed that each fiber type (slow, intermediate, and fast) has a unique distribution within the fascicles, in both conditions. However, chronic undernutrition modified the intra-fascicular fiber type distributions, except in the F2. Altogether, these results showed that the methodology herein proposed allows for analyzing fiber type organization and distribution modifications. On the other side, we show that chronic undernutrition alters not only the fiber type composition but also the organization and distribution, which could affect the muscle functioning, and ultimately, its behavior (e.g., locomotion).

Single vs. Combined Therapeutic Approaches in Rats With Chronic Spinal Cord Injury.

The regenerative capability of the central nervous system is limited after traumatic spinal cord injury (SCI) due to intrinsic and extrinsic factors that inhibit spinal cord regeneration, resulting in deficient functional recovery. It has been shown that strategies, such as pre-degenerated peripheral nerve (PPN) grafts or the use of bone marrow stromal cells (BMSCs) or exogenous molecules, such as chondroitinase ABC (ChABC) promote axonal growth and remyelination, resulting in an improvement in locomotor function. These treatments have been primarily assessed in acute injury models. The aim of the present study is to evaluate the ability of several single and combined treatments in order to modify the course of chronic complete SCI in rats. A complete cord transection was performed at the T9 level. One month later, animals were divided into five groups: original injury only (control group), and original injury plus spinal cord re-transection to create a gap to accommodate BMSCs, PPN, PPN + BMSCs, and PPN + BMSCs + ChABC. In comparison with control and single-treatment groups (PPN and BMSCs), combined treatment groups (PPN + BMSCs and PPN + BMSCs + ChABC) showed significative axonal regrowth, as revealed by an increase in GAP-43 and MAP-1B expression in axonal fibers, which correlated with an improvement in locomotor function. In conclusion, the combined therapies tested here improve locomotor function by enhancing axonal regeneration in rats with chronic SCI. Further studies are warranted to refine this promising line of research for clinical purposes.

Changes in Heart Rate Variability in Patients with Spleen-Qi Deficiency Syndrome.

Many functional diseases are related to dysautonomia, and heart rate variability has been used to assess dysautonomia. However, heart rate variability has not been studied in Spleen-Qi deficiency syndrome (SQDS). Healthy volunteers (n = 37) and patients with SQDS (n = 67), recruited from the Clinic of the State University of Ecatepec Valley were included in the study. Outcome measures were average heart rate, standard deviation of the normal-to-normal heartbeat intervals, low frequency (LF), high frequency (HF) power, and the LF/HF ratio. Also, intestinal peristalsis, gastrointestinal symptoms (GSs), fatigue, and level of attention were measured. Standard deviation of the normal-to-normal heartbeat intervals (17 ± 2.3%) and HF (14 ± 3.1%) were lower in SQDS patients (17 ± 1.3%) than in healthy volunteers. SQDS patients had higher heart rate, LF power, LF/HF ratio, and fatigue scores (9.6 ± 1.12%, 16 ± 2.1%, 22 ± 3.8%, and 21 ± 4.1%). The fatigue correlated positively with the LF/HF ratio and negatively with HF power. The SQDS group had lower concentration performance (16.2 ± 1.9%) in the d2 test. The intestinal peristalsis showed a reduction (15 ± 1.3%) as compared with control. GS score and peristalsis correlated negatively with HF. Our results suggest that the pathology of SDQS could be associated with a low vagal tone which causes a decrease in peristalsis, increased fatigue, reduced attention, and appearance of GSs.

Physiological changes of growth hormone during lactation in pup rats artificially reared.

During the lactation period, rat pups are fed by the dam, and the patterns of mother-pup interaction change during this period. Additionally, there are changes in feeding; first, mother´s milk is the only food needed for sustenance, and later, it is combined with solid food and water. GH serum concentrations depend on both maternal-pup interaction and energy metabolism. In the artificial rearing (AR) procedure, pups are deprived of mother-pup interaction, and the feeding pattern is controlled. This rearing paradigm has been used in rats to analyze the effects of maternal deprivation on social behavior. In the present study, we analyzed the variation in GH, acylated ghrelin and IGF-1 serum concentrations throughout the lactation period in AR pups. At pnd7, the maternal rearing (MR) pups responded to a 4 h fast with a drop in GH serum concentration, which is a well-known response to maternal deprivation. GH serum levels in the AR pups did not change, suggesting an adaptation phenomenon. A dopamine inhibitory effect of GH secretion was observed in pnd7 cultured somatotropes, suggesting dopamine regulation of GH secretion at this age. Acylated ghrelin serum levels in the AR pups showed an inverted pattern compared to that in the MR pups, which was related to the artificial feeding pattern. IGF-1 serum levels were lower in the AR pups than in MR pups, which was associated with hepatic GH resistance and with low Igf1 mRNA expression at pnd7. Interestingly, at pnd14, both pup groups showed high hepatic Igf1 mRNA expression but low IGF-1 serum levels, and this was inverted at pnd21. However, serum glucose levels were lower in the AR pups at pnd14 but reached the same levels as the MR pups at pnd21. Moreover, hepatomegaly and higher hepatic GH-receptor levels were observed in the AR pups at pnd21, which was in agreement with an absence of a solid food meal. During AR, the pups lost the maternal interaction-stimulated GH secretion, which correlated with lower IGF-1 serum levels during the first week of postnatal development. Later, the AR pups exhibited hepatic responses, in order to satisfy the metabolic demand for the normal weaning, with low carbohydrates levels in their meal.