The Search for Diagnostic Criteria to Divide the Wistar Rat Population into Phenotypes during Modeling of Post-Traumatic Stress Disorder.

The levels of circulating hormones (corticosterone, testosterone, and leptin) and interleukins were studied in sexually mature male Wistar rats against the background of post-traumatic stress disorder (predator threat stress). It was found that in addition to the previously used anxiety index determined by animal behavior, the population of stressed individuals can be divided into stress-resistant and stress-sensitive phenotypes by the level of leptin and the index of anabolism (testosterone/corticosterone ratio). For the first time, it was determined that in stress-resistant rats, the levels of leptin and the testosterone/corticosterone index exceeds the control values, while in stress-sensitive individuals, these indicators are much lower.

Drawbacks and Unexpected Advantages of the Response to Modeling Posttraumatic Stress Disorder in Old Wistar Rats.

In modeling post-traumatic stress disorder (PTSD), old Wistar rats exhibit the same general signs of a PTSD-like condition as young rats do. The ratio of testosterone to corticosterone levels was assessed as a new index and proved to provide a guideline for dividing the rat population into low- and high-anxiety groups when modeling PTSD. Several features were observed in behavior, psycho-emotional manifestations, hormone levels, and myocardial state in old rats.

Changes in the Expression of Pluripotency Factor Oct-4 and Intensity of Apoptosis in the Uterus during Spontaneous and Immune-Dependent Abortions in Mice.

We studied the expression of pluripotency factor Oct-4 and the intensity of apoptosis in the uterus during spontaneous and immune abortions in mice. Increased expression of factor Bax and reduced protein Bcl-2 synthesis in cells of the decidual membrane and decreased Oct-4 expression in the myometrium and perimetrium were detected. Thus, both spontaneous and immune-dependent abortions impair the apoptosis processes in the decidua and the formation of a pool of Oct-4 cells in the uterus.

Analysis of Healing of Rat Uterine Wall After Full-Thickness Surgical Incision.

We studied the dynamics of morphological changes in the operated segment of the uterine horn of Sprague-Dawley rats during the first 2 weeks of the wound-healing process after a full-thickness surgical incision with regard to the estrous cycle phase. Morphometric parameters of injured uterine right horn were compared with those in the intact left horn of the same animal as a control of changes determined by the hormonal background. It was found that the uterine epithelium in the focus of injury was restored as soon as on day 2 after surgery under the influence of estrous cycle hormones.

Comparison of the Adaptive Capacity in Old and Young Wistar Rats to Stress Exposure and Acute Hypoxic Hypoxia.

We compared behavioral and psychoemotional manifestations of young and old male Wistar rats in elevated plus-maze, the levels of corticosterone and testosterone, as well as the resistance to acute hypoxic hypoxia before and after stress exposure (10-min swimming sessions over 10 days). The behavioral characteristics, responses of the main stress hormone corticosterone, and resistance to acute hypoxic hypoxia were identical in both age groups before and after stress. A distinguishing feature was pronounced flattening of the psychoemotional manifestations in old animals.