ABSTRACT
BACKGROUND: The relationship between the activity of the epiphysis and gonads in rats of different sex and age in different seasons of the year was determined by studying the levels of melatonin and testosterone in the blood plasma. Determination of the levels of melatonin and testosterone in the serum of rats was carried out by enzyme-linked immunosorbent assay. To assess the relationship between the levels of melatonin and testosterone the correlation coefficient was calculated. Based on the study of the levels of melatonin and testosterone in serum the circannual relationship between the activity of the pineal gland and gonads in males of reproductive age has been determined. In females, the relationship between the levels of melatonin and testosterone without the circannual dependence has been determined. The strongest correlation between melatonin and testosterone is present in males at the age of 9 months in autumn, and it corresponds to the human age of 29-30 years.
Subject(s)
Age Factors , Epiphyses/physiology , Gonads/physiology , Seasons , Animals , Female , Humans , Male , Melatonin/metabolism , Rats , Reproduction , Sex FactorsABSTRACT
The aim of the research was to study the state of melatonin-positive-labeled cells (MPLC) of GM in desynchronosis in rats of different age and gender. 780 sections of the pyloric part of the gastric mucosa were studied in rats of both genders at the age of 9, 15 and 20 months. Animals were divided into intact control groups and the groups of the animals kept under the conditions of continuous light for 14 days - desynchronosis. The study was performed by the method of immunohistochemical staining with the primary antibodies to melatonin (Biorbyt, UK) and the secondary Alexa Fluor 488-conjugated antibody (Abcam, UK). In the course of the research it was found that MPLC in all experimental groups were mainly located in the basal and middle segments of the tubular glands of gastric mucosa and were represented by three types of cells. In desynchronosis the number of melatonin-positive-labeled cells significantly reduced in almost every age group, with the exception of females at the age of 20 months. Thus in elderly males and females the number of melatonin-positive-labeled cells of type III increases, whereas in young and mature males it decreases, and cells of type I predominate.
Subject(s)
Circadian Rhythm , Gastric Mucosa/radiation effects , Melatonin/metabolism , Age Factors , Animals , Cell Count , Female , Gastric Mucosa/cytology , Gastric Mucosa/metabolism , Light , Male , Photoperiod , Rats , Sex FactorsABSTRACT
In male rats of different ages, we studied the functional activity of the pineal gland and the gonads during different seasons by determining the levels of melatonin and testosterone in the blood serum. It was found that the highest levels of melatonin observed in male rats in summer and winter, and the lowest - in autumn. The lowest level of melatonin has been established in the group of rats aged 9 months - 127.28+5.11 pmol/l that was 22% lower than the level of melatonin in 3 months old rats (P!0,05), and 20% below the level of melatonin in rats of 15 months old (Ps0,05). The highest level determined in rats aged 3 months (corresponds to the age of man -14 years old), the lowest - in rats 20 months-(corresponds to the age 55-56 years old). At the same time, the low level of melatonin was defined in rats aged 9 months in the autumn (corresponds to the age of man 29-30 years). In the study of testosterone levels in different seasons it was found that the highest level in all age groups presents in autumn, the lowest - in winter. When comparing the levels of testosterone in different age groups, it was determined that the fall of the highest level of testosterone present in the blood of males age 9 months and 15 months, which corresponds to the age of 29-30 and 43-44 of human years. Significant difference between the levels of testosterone in the groups that correspond to the reproductive age - rats of age 3, 9 and 15 months, are present only in the autumn; spring and summer - significant differences between the levels of testosterone absent. The degree of correlation differed in rats of different ages in different seasons: the highest correlation between the levels of melatonin and testosterone was determined in rats aged 9 months in autumn. The correlation coefficients in rats aged 20 months old have been weak - from 0.05 in the spring to 0.17 in autumn that shows the changes in neurohormonal regulation which occur with age.
