Effect of exercise training on aging-induced changes in rat papillary muscle.

Background: The effects of aging on papillary muscle have been widely demonstrated, but no data on the effects of exercise on the age-related changes are available.

Objective: To analyze the effects of aging on the morphological and quantitative properties of papillary muscle and investigate whether a long-term moderate exercise program would exert a protective effect against the effects of aging.

Methods: We used electron microscopy to study the density of myocytes, capillaries and connective tissue and the cross-sectional area of myocytes of the papillary muscle of the left ventricle of 6- and 13-month-old untrained and exercised Wistar rats.

The developing and restructuring superior cervical ganglion of guinea pigs (Cavia porcellus var. albina).

Post-natal development comprises both maturation (from newborn to adult) and ageing (from adult to senility) and, during this phase, several adaptive mechanisms occur in sympathetic ganglia, albeit they are not fully understood. Therefore, the present study aimed at detecting whether post-natal development would exert any effect on the size and number of a guinea pig's superior cervical ganglion (SCG) neurons. Twenty right SCGs from male subjects were used at four ages, i.

Low-intensity treadmill exercise-related changes in the rat stellate ganglion neurons.

Stellate ganglion (SG) represents the main sympathetic input to the heart. This study aimed at investigating physical exercise-related changes in the quantitative aspects of SG neurons in treadmill-exercised Wistar rats. By applying state-of-the-art design-based stereology, the SG volume, total number of SG neurons, mean perikaryal volume of SG neurons, and the total volume of neurons in the whole SG have been examined.

Asymmetric post-natal development of superior cervical ganglion of paca (Agouti paca).

Functional asymmetry has been reported in sympathetic ganglia. Although there are few studies reporting on body side-related morphoquantitative changes in sympathetic ganglion neurons, none of them have used design-based stereological methods to address this issue during post-natal development. We therefore aimed at detecting possible asymmetry-related effects on the quantitative structure of the superior cervical ganglion (SCG) from pacas during ageing, using very precise design-based stereological methods.

Placental microstructure and efficiency in cloned bovines: a design-based stereological approach.

Somatic nuclear transfer allows scientists to produce identical copies of individuals (clones) and offers the potential for research in various fields. However, the production of cloned bovines is inefficient, partly because of high rates of embryonic mortality associated with abnormal placental development, although the exact mechanisms are still unclear. In the present study, we have applied design-based stereological methods to quantify placental morphology in cloned and non-cloned Nelore bovines (280-297 days of gestation).

Macro- and microstructure of the superior cervical ganglion in dogs, cats and horses during maturation.

The superior cervical ganglion (SCG) provides sympathetic input to the head and neck, its relation with mandible, submandibular glands, eyes (second and third order control) and pineal gland being demonstrated in laboratory animals. In addition, the SCG's role in some neuropathies can be clearly seen in Horner's syndrome. In spite of several studies published involving rats and mice, there is little morphological descriptive and comparative data of SCG from large mammals.

Size and number of binucleate and mononucleate superior cervical ganglion neurons in young capybaras.

The total number of neurons in the superior cervical ganglion (SCG) of adult capybaras is known from a previous study, where a marked occurrence of binucleate neurons (13%) was also noted. Here, distribution, number and fate of binucleate neurons were examined in younger, developing capybaras, aged 3 months. The mean neuronal cross-sectional area was 575.

Postnatal-related changes in the size and total number of neurons in the caudal mesenteric ganglion of dogs: total number of neurons can be predicted from body weight and ganglion volume.

Aging is mostly characterized by a progressive decline of neuronal function that involves both the central and the peripheral nervous system. The aging process is accompanied by changes in either the number or the size of neurons. However, these data are controversial and not very well known in the sympathetic ganglia of large mammals.

The muscular organization of the stomach of capybara (Hydrochoerus hydrochaeris): an architectural view.

Twenty-two stomachs from adult capybaras were used in this study, and an acid digestion mesoscopic technique was pursued using different concentrations of nitric acid to observe the muscular organization of the stomach. The capybara's stomach possessed a muscular coat composed of four layers or strata: external longitudinal, external oblique, circular and internal oblique. Also, the cardiac and pyloric sphincter muscles were comprised of three or two different layers, respectively.

Preservation of cadavers for surgical technique training.

Objective: To evaluate a technique for preservation of organoleptic tissue characteristics (color, odor, texture, and flexibility) in cadavers used for surgical instruction.

Study Design: Experimental study.

Animals: Forty-three canine cadavers.

Estimate of size and total number of neurons in superior cervical ganglion of rat, capybara and horse.

The superior (cranial) cervical ganglion was investigated by light microscopy in adult rats, capybaras (Hydrochaeris hydrochaeris) and horses. The ganglia were vascularly perfused, embedded in resin and cut into semi-thin sections. An unbiased stereological procedure (disector method) was used to estimate ganglion neuron size, total number of ganglion neurons, neuronal density.