Effect of intensive noise on prohibitively seizure brain of white rats and their offspring with dependence on gender, age, initial sensitivity and reactivity, frequency noise irritation
In this article is studied of the influence of sound impacts on the threshold of convulsive activity of brain (TCAB) in rats of the two lines and their progeny of the first generation (n = 314) depending on initial sensitivity and reactivity to sound impacts, age, sex, mode of presentation of sound impacts using a intense (86 decibels) sound impacts(SI). During the experiment in the population of the initial highliminal Wistar rats about 3.85 % of immature rats (1 months-old) and 33.33 % of the onset of puberty rats (2 months-old) and 9.62 % of adult ones (6 and 20 months-old) had epileptiform audiogenic convulsive assault (EACA) during to the first sound impact and, accordingly, about 7.7, 16.7, 7.69 % had only audiogenic motor excitation (AME) that did not transform to any convulsive assaults. Rare (over 2 days on 3 day; gentle, coaching mode) 30-multiple sound impacts led to decrease their TCAB in 33.33 % of 2 months - old rats (up to 24 SI), in 13.6 % of the 6 months-old (up to 30 SI), in 4.8 % of 20 months-old (variably, 13.3 % SI) and, accordingly, in 8.7, 16.7, 13.6 and 4.8 % of rats it led to their AME. After 3 months repeated cycle of 30-multiple rare SI did not decrease their TCAB on the remaining after the first cycle of SI to high-threshold rats. Rare 30-multiple SI in the line of Krushinskii - Molodkina (K-M) of mature rats with genotypical determinate low TCAB did not affect on the reactivity and sensitivity to SI. There were lengthened and aggravated of EACA and course of post attack (reparative) period. Frequent sound impacts (i.e. daily, depleting mode) reduced the latent period with lengthened and prolonged duration of EACA, lengthened and aggravated post attack disorders, and to 12 SI animals stopped to respond EACA to SI. They ate and drank poorly, but after 7-14 days of break EACA was recovered. During affecting by sound impacts in 2 months-old progeny of the first generation from low-threshold line of K-M rats suffered the impact of 30-multiple rare SI for all animals died as a result of clonical convulsions without recovery of breathing and cardiac activity. 6 months-old progeny of the first generation from high-threshold Wistar rats suffered the 30-multiple rare sound impacts did not react by epileptiform audiogenic convulsive paroxysm to acoustic stress.