Effect of aging on the reparative ability of rat gastric mucosa after acute injury

The aim of this study was to investigate the effect of aging on the regenerative capacity of the gastric mucosa after acute injury. This study was conducted on 36 male albino rats for the study of mucosal injury by using 2 M NaCI. The animals were equally divided into 3 subgroups aged 4, 12, 24 months. The animals in each subgroup were killed 1, 6, 24, and 48 hours after intake of NaCI. Paraffin sections were prepared from specimens of the gastric mucosa of rats and stained by Hx and E, PAS and Alcian blue/PAS. One hour postinjury, the gastric mucosa of young rats showed a lesion index of 70.1% and the grade of mucosal injury was classified as grade I. The gastric mucosa of old rats demonstrated a lesion index of 88.3%, and the mucosal injury was grade II. The gastric mucosa of senescent rats demonstrated a lesion index of 100% with mucosal injury of grade III. Six hours post-injury, the lesion index of young rat gastric mucosa was 10.7%, several areas of regeneration with groups of flattened cells covering most of the mucosal surface were observed and further expansion of the neck region was demonstrated. The gastric mucosa of old rats showed a lesion index of 26.5%, and regeneration was detected in some areas. In senescent rats, the lesion index was 74.9%, the neck region was expanded and the mucosal surface was still mostly exposed with no signs of regeneration. Twenty four hours post-injury, the mucosal surface of young rats showed complete regeneration with small, cubical cells having rounded nuclei. Partial re-establishment of the glandular structure pattern was also observed. On the other hand, the gastric mucosa of old rats showed a lesion index of 10.0%, and clumps of proliferating cells were seen covering most of the mucosal surface. The gastric mucosa of senescent rats showed a lesion index of 37% with only intermittent clusters of regenerating epithelial at the same time post-injury. Forty eight hours post-injury, the glandular structure of young rat gastric mucosa has been completely re-established and the regenerated epithelial cells appeared normal. The gastric mucosa of old rats also showed evidence of regeneration and partial re-establishment of the glandular architecture and gastric pits. However, gastric mucosa of senescent rats demonstrated a lesion index of 10.2%, partial healing with focal sites of healing failure and incompletely reestablished glandular architecture. Aging is associated with increased susceptibility of the gastric mucosa to injury and delayed repair process. Irritating foods and drugs such as NSAIs should be avoided in the elderly and if necessary, their dose should be adjusted and proper follow up should be provided to avoid severe gastric mucosal injuries

Effect of atrial extract on the ACTH and cortisol response to stress in rats

Twenty male albino rats were divided into two groups: Control group [receiving intravenous placebo] and experimental group [receiving intravenous atrial extract [80 mug/kg body weight] before being subjected to stress induced by ether inhalation for 60 seconds]. Plasma ACTH, cortisol, aldosterone, glucose and sodium were estimated for all rats basally as well as 15, 30 and 45 minutes after ether inhalation. In placebo-treated rats, ether inhalation resulted in statistically significant increase in plasma ACTH and cortisol. In atrial extract-treated rats, the ACTH and cortisol responses to stress were statistically suppressed when compared with the control response. No changes in plasma aldosterone, glucose or sodium were detected

study of some trace elements in fingernail and hair of Egyptian bilharzial patients using short neutron activation

The concentration of 10 elements has been determined in fingernail and hair of four groups representing normal and hepatosplenic [bilharzial] subjects. Samples were collected from rural inhabitants to the east of Alexandria City and irradiated with thermal neutrons from a Triga Mark III Reactor, for 10 minutes. Measurements were made using HPGe detector, ADC and PDP 11 /34. The analysis were performed using the RAYGUN program. The results showed an increase in the concentration of AI, Cl and I in both fingernail and hair of bilharzial patients than normal while Mg, Ca, K, Mn, Cu, and Sr decreased. Most of the elements showed a higher concentration in fingernail than in hair

Effects of cold exposure and starvation on plasma glucose insulin and catecholamine levels in albino rats

The metabolic interactions of cold exposure and starvation on plasma glucose, insulin and catecholamine levels were studied in male albino rats. Cold exposure [48 hr at 5C] significantly reduced plasma glucose and insulin levels and increased plasma noradrenaline level. Cold exposure of starved rats [48 hr at 5C] significantly reduced plasma glucose and insulin levels with no change in plasma catecholamine levels. Results from this study indicated that, cold exposure and starvation act synergistically in decreasing the capacity of the pancreatic islets to secrete insulin and that glucose utilization may be enhanced with barely detectable insulin levels in cold starved rats

Prenatal development of the human parotid gland

The prenatal development of the human parotid gland has been investigated in 26 fetuses from the 10th week of gestation to full term. At 10-12 weeks, the gland was composed of primitive ducts and terminal buds of primitive acini surrounded by loose mesenchyme. The acini continued to increase in number and size till full term. At 16 weeks, the lobulation of the developing gland was recognizable together with differentiation of the primitive ducts into intra- and interlobular ducts. At 20 weeks, both intercalated and striated ducts were distinguished and their number increased gradually with age. At birth, the ducts and acini appeared fewer and less crowded than those of the adult and the gland appeared devoid of fat cells. PAS- and AB-positive secretory materials appeared in the epithelial cells of both ducts and acini and in their lumina during the 12th week. This secretory activity persisted throughout pregnancy. The functional significance of the secretory products is discussed