ABSTRACT
The pharmacological manipulation with selective inhibitor of serotonin reuptake (SSRIs) can modify the operation of the serotonergic system and may facilitate or inhibit the action of this system, inducing changes in the morphology of the skeletal muscle of rats. The objective of this study was to evaluate the action of the treatment with fluoxetine during the critical period of the animal´s life on development of the soleus and lateral gastrocnemius muscles, under the aspects of weight, the number of nuclei of myocyte cells and cross-sectional area of muscle fibers. Twenty four (30 and 90-day-old) male Wistar rats were used. They were treated with saline solution (NaCl 0.9%; 1 ml/100 g of body weight) or fluoxetine (10 mg; 1 ml/100g of body weight). The animals were divided in Saline Group (GS-30 and GS-90) and Fluoxetine Group (GF-30 and GF-90). The fluoxetine group showed a reduction on weight (g) of soleus (p=0.046) and lateral gastrocnemius (p=0.02) muscles in rats with 90 days. A lesser number of myonuclei was observed in fluoxetine group than saline group of 30 days (soleus, p<0.001; lateral gastrocnemius, p0.007) and 90 days (soleus, p=0.002; lateral gastrocnemius, p0.038). The cross section area of fluoxetine groups is also smaller than the saline groups with 30 days (soleus, p=0.03; lateral gastrocnemius, p=0.041) and 90 days (soleus, p=0.042; lateral gastrocnemius, p=0.012). The treatment of fluoxetine during the critical period of development of the nervous system of rats, causes early changes in the structure of muscle fibers that seem to be related to reducing the weight of the soleus and gastrocnemius muscles only in late stage of the animal's life. Thus, the dosage used ISRS, suggests an inhibitory effect of 5-HT in relation to variables on the development of the skeletal muscle tissue of rats.
La manipulación farmacológica con inhibidores selectivos de la recaptación de la serotonina (ISRS) pueden cambiar el funcionamento del sistema serotoninérgico y facilitar o inhibir la acción de este sistema, induciendo cambios en la morfología del músculo esquelético de ratones. El objetivo fue analizar los efectos de la manipulación farmacológica neonatal con fluoxetina en el desarrollo de la masa muscular, número de núcleos y área de la sección transversa de las fibras de los músculos sóleo y gastrocnemio lateral. Se utilizaron 24 ratones Wistar machos, de 30 y 90 días de edad, tratados con solución salina (NaCl 0,9%, 1m/100 g de peso corporal) y fluoxetina (1 mg; 1 ml/100 g de peso corporal). Los animales fueron divididos en grupos con solución salina (GS-30 y GS-90) y fluoxetina (GF-30 y GF-90). El grupo tratado con fluoxetina mostró una reducción de peso (g) de los músculos sóleo (p=0,0046) y gastrocnemio lateral (p=0,02) en 90 días. Además, se observó en este mismo grupo una reducción de núcleos en 30 días (M. sóleo, p<0,001; M. gastrocnemio lateral, p0,007) así como en el período de 90 días (M. sóleo, p=0,002; M. gastrocnemio lateral, p0,038). También se observó reducción del área de la sección transversal en los animales tratados con fluoxetina durante el período de 30 días (M. sóleo, p=0,03; M. gastrocnemio lateral, p= 0,041;) y 90 días (M. sóleo, p=0,042; M. gastrocnemio lateral, p=0,012). El tratamiento con fluoxetina durante el período crítico del desarrollo del sistema nervioso de ratones, induce cambios prematuros en la estructura de la fibra muscular, los que parecen estar relacionados con la reducción de peso de los músculos sóleo y gastrocnemio en una fase tardía de vida del animal. En consecuencia, la dosis utilizada de ISRS, sugiere un efecto inhibidor de la 5-HT, en relación a las variables estudiadas sobre el desarrollo del tejido muscular esquelético de ratones.
Subject(s)
Animals , Male , Rats , Fluoxetine/pharmacology , Selective Serotonin Reuptake Inhibitors/pharmacology , Muscle, Skeletal/drug effects , Organ Size/drug effects , Rats, Wistar , Muscle Fibers, Skeletal/drug effects , Muscle Cells/drug effectsABSTRACT
Objective: To study the effect of 4-6 weeks' treadmill training of male SD rats on the contractile function of their gastrocnemius myosin heavy chain (MHC). Methods: Forty male SD rats were randomly divided into control group and training group. The treadmill training of the training group rats was incessantly performed for 4-6 weeks at an intensity of about 75% VO 2max (18.5-24 m/min, gradient of 0°, each training session lasting 50 minutes, twice a day). The content of gastrocnemius MHC mRNA was tested by reverse transcription polymerase chain reaction (RT-PCR), and the changes of muscle fibre and its cross-section area (CSA) were measured using immunohistochemistry. Electric stimulation tests were used to determine the maximal tension of isometric contraction of the post-training gastrocnemius. Results: Circled digit one After continuous treadmill training for 4-6 weeks, we found that the content of the total MHC, MHC I, MHC II x, MHC II a mRNAs was 105%, 105%, 109% and 108% of that in the resting control group, respectively, and the MHC II b mRNA content did not change significantly. The percentage of MHC I mRNA in the total MHC mRNA increased while that of MHC II mRNA decreased after aerobic training. Circled digit two The slow type of fibre type I was the main part of the MHC after training and the CSA of the muscle fibres increased simultaneously. Circled digit three The maximal tension of isometric contraction by pulse stimulation of square wave in the training group increased significantly compared with that in the control group (P<0.01). Conclusion: The findings indicate that aerobic exercise may promote an increase in the contractile function of MHC.
ABSTRACT
Assessment of the optic nerve head or the retinal nerve fiber layer is essential for the early diagnosis and monitoring of glaucoma. We compared mean retinal nerve fiber layer[RNFL]thickness with Average, and compared RNFL CSA with Integral between Heidelberg Retina Tomograph[HRT] and GDx nerve fiber analyzer[GDx]at global, superior, inferior, nasal and temporal area. Mean RNFL thickness in HRT was significantly greater than Average in GDx at all quadrants[p<0.001], and correlated with Average at global, superior and inferior area[p<0.05]. RNFL CSA in HRT was significantly greater than Integral in GDx at superior, inferior and nasal quadrants[p<0.001], and correlated with Integral at superior and inferior quadrants[p<0.05]. In conclusion, the two parameters related to nerve fiber layer in HRT were measured greater than those in GDx. Correlations of the above parameters between HRT and GDx were mainly present at superior and inferior quadrant. These results may come from regional difference in measurement between HRT and GDx, and uncorrected disc tilting in HRT appears to have adverse effects on the correlations of the above parameters between HRT and GDx at nasal or temporal quadrant.
Subject(s)
Early Diagnosis , Glaucoma , Nerve Fibers , Ophthalmoscopes , Optic Disk , Retina , RetinaldehydeABSTRACT
The purpose of this study was to investigate the effects of regular swimming, walking and aerobic exercise on bone density, muscle strength and % body fat in elderly women (above average 65-year-old). Thus, the study suggested that there is basic data for osteoporosis prevension, physical fitness development and health management. This research provided as follows ; 1. The bone density increases of lumbar and femur (femoral neck, ward's triangle, trochanter) site were found as ordinal of aerobic group, walking group, swimming group and control group. 2. The measuring site of muscle strength increases and % body fat decreases were found as ordinal of aerobic group, walking group, swimming group and control group. 3. The bone density of lumbar and femur get significant correlation coefficient with back strength, leg extension and % body fat in the control group. 4. The bone density of lumbar and femur were significant correlation coefficient with back strength and leg extension in the swimming group. Furthermore we can find significant correlation coefficient between bone density of lumbar and % body fat. 5. There are significant correlation coefficient between bone density of lumbar and back strength, leg flexion, leg extension in the walking group. Foremore we can find significant correlation coefficient between bone density of femur and back strength, leg extension and % body fat. 6. There are significant correlation coefficient between bone density of lumbar and grip strength, back strength, leg flexion, leg extension. Furthermore we can find significant correlation coefficient between bone density of femur and grip strength, back strength, leg flexion, leg extension and arm extension. But % body fat would be correlated with bone density of lumbar only. 7. The bone density of the sum of four group in the lumbar and femur was correlated with muscles strength and % body fat. Although swimming exercise of elderly women wouldn't effect the increase of bone density, it influence to muscle strength and leg strength increase. However, walking and aerobic exercise were considered as optimal exercise type for bone density and muscle strength increases. It would be suggested that the study supplies some information for increasing physical fitness and bone density if lifestyle and amount of calcium ingestion so on can be controlled and the exercise prescription of individual according to physical fitness level has been given.