Charakterystyka okołodobowej funkcji wydzielniczej nerek w przypadku zahamowania syntezy tlenku azotu ze szczególnym uwzględnieniem wpływu melatoniny w warunkach prawidłowej funkcji szyszynki

Svitlana B. Semenenko, Svitlana U. Karatieieva, Oksana V. Bakun, Ksenia V. Slobodian, Alla I. Peryzhniak

HIGHER STATE EDUCATIONAL INSTITUTION OF UKRAINE “BUKOVINIAN STATE MEDICAL UNIVERSITY”, CHERNIVTSI, UKRAINE

 

ABSTRACT

The features of сhronorhythmic alterations of excretory renal function under the physiological conditions of the pineal gland (PG) under the influence of a blockade of synthesis of nitrogen monoxide (NO) and melatonin correction were investigated.

The aim: Aim of our work was to investigate circadian characteristic of kidney excretory function influenced by nitrogen monoxide synthesis blockade under conditions of pineal gland normal with peguliarities of melatonin effect.

Materials and methods: The experiments were conducted on 72 mature non-linear albino male rats with their body mass 0,15-0,18 kg. The animals were kept under vivarium conditions at a stable temperature and air humidity fed on a standard dietary intake.

Results and conclusions: Based on a series of studies, the blockade of NO synthesis and melatonin correction resulted in a decrease in the average daily urinary output and a decrease in the removal of potassium ions from urine, relative to control, during the observation period. Therefore, the clarification of the features of сhronorhythmic alterations of the excretory renal function under the physiological conditions of the PG under the influence of blockade of NO synthesis and melatonin correction is important for the knowledge of the mechanisms of occurrence and development of pathological conditions, which will enable to improve the early diagnosis, improve the treatment of renal pathology and timely preventative measures.

 

Wiad Lek 2018, 71, 7, -1335

 

Introduction

According to literature it is known that the vital activity of an organism is provided by a clearly coordinated system of biological rhythms [1, 2]. The hormone that regulates the rhythms of the organs and tissues are melatonin [3, 4, 5]. It provides high reliability of the functional state of the organism. In the complex mechanism of kidney function control [6] the prominent integrative role belongs to the local intracellular messenger – nitrogen monoxide (NO) [7]. The kidneys are characterized by сircadian оrganization of functions [8]. However, the peculiarities of the chrono-organization and the mechanisms of the participation of hormones in the biorhythmic regulation [9] of the excretory function of the kidneys remain insufficiently studied [10].

The aim

Aim of our work was to investigate circadian characteristic of kidney excretory function influenced by nitrogen monoxide synthesis blockade under conditions of pineal gland normal with peguliarities of melatonin effect. Main tasks of research: the study of circadian characteristic of kidney excretory function influenced by nitrogen monoxide synthesis blockade under conditions of pineal gland normal with peguliarities of melatonin effect.

Materials and methods

The experiments were conducted on 72 mature non-linear albino male rats with their body mass 0,15-0,18 kg. The animals were kept under vivarium conditions at a stable temperature and air humidity fed on a standard dietary intake. The control group included animals (n=36) kept under conditions of usual light regimen (12.00L:12.00D) during 7 days. The experimental group included animals (n=36) injected with N-nitro-L-arginine (L-NNA) in the dose of 20 mg/kg during 7 days under the normal conditions of pineal gland (12.00L:12.00D) and melatonin in the dose of 0,5 mg/kg during 7 days simultaneously. On the 8th day the animals were exposed to 5% water load with heated to room temperature water supplied and the parameters of the kidney excretory function under conditions of forced diuresis were investigated.

The experiments were conducted with 4 hour interval during the day. The diuresis, concentration and excretion of potassium ions, concentration and excretion of creatinine, glomerular filtration rate, relative water reabsorption, endogenous creatinine concentration index, protein concentration and excretion were studied. The results were statistically processed by means of “Cosinor-analysis” method and parametric methods of variation statistics. The diagnostics of functional peculiarities was based on the analysis of changes of the following characteristics: daily mean, amplitude, acrophase and circadian rhythm curve shape. Individual chronograms for every animal obtained were distributed by the principle of maximal acrophase identity and intersecting for every group of chronograms daily mean, amplitude and phase structure (by the interval of time between acro- and bathyphase) were calculated by “Cosinor-analysis” method. All the stages of the experiment were carried out keeping to the major requirements of the European Convention on Human Attitude to Animals.

The experimental data obtained were processed on personal computers with the program package EXCE-2003 (Microsoft Corp., USA). The values of arithmetic mean sampling (х), its dispersion and mean error (Sx) were calculated. To detect probable differences of the results in the experimental and control groups of animals Student (t) coefficient was determined, after that probability of sampling differences (p) and mean confidence interval by the tables of Student distribution were detected. The values were considered reliable with р<0,05.

Results and discussion

Kidney functions are subordinated to accurate circadian organization in the control animals. At blockade of NO synthesis under conditions of melatonin, significant changes in the daily diuresis rhythm (table I) were observed. The architectonic rhythm of urination was inverse in relation to the chronograms of animals that were under conditions of hyperfunction of the pineal gland (PG) with blockade of synthesis of NO and control animals. The batiphase of rhythm was detected at 12.00 hr, the maximum rhythm displacement was shifted from 8.00 hr to 16.00 hr relative to the control group of animals and in animals that were administered L-NNA in the background of hyperfunction of the PG it was at 20.00 hr. The chronorhythmic rearrangements in animals that blocked the synthesis of NO on the background of hyperfunction of the PG and permanent illumination suggest that the blockade of NO synthesis and the use of melatonin changes the phase structure of the rhythm. The administration of melatonin against the backdrop of oppression of the synthesis NO caused a decrease in the diuresis daily mean in comparison with the control group (fig. 1). The combination of blockade of synthesis NO with the correction of melatonin in animals with hypo- and hyperfunction of PG in conditions of blockade of synthesis NO had no additive effect.

The changes in diuresis in animals administered melatonin under the blockade of NO synthesis led to a violation of the processes of ultrafiltration (table I). Features of the chronorhythm of the velocity of glomerular filtration were characterized by an inverse character with an acrophase of 4.00 hr and a bytephase at 8.00 hr. The attention was drawn to a decrease in the level of the indicator at all the study intervals of the day compared with control animals and animals with hypofunction PG of blockade of synthesis of NO an increase in the index for rats with hyperfunction of the PG, which was administered L-NNA, at 8.00, 12.00 and 16.00 hr, at 8.00 and 24.00 hr it was 2.6 times lower than control values and at 8.00 hr a 2 times higher than that of animals that were under hyperfunctional PG with blockade of synthesis NO. The daily mean was lower than that of a control animals and rats with hypofunction of PG in the blockade of NO synthesis but higher relative to the PG hyperfunction animals that were administered L-NNA indicating the total effect of blockade NO synthesis and hypofunction of PG (fig. 2).

The decrease in the velocity of glomerular filtration led to a slight decrease in the relative reabsorption of water which counterbalanced glomerulo-tubular processes (table I). The architectonic rhythms of these parameters were different, the maximum values were recorded at different intervals of the day. This indicated a potentiating effect of the blockade of NO synthesis in terms of melatonin correction. Despite the decrease in the rate of ultrafiltration there was a decrease in the concentration of creatinine in blood plasma (table I) except for 8.00 hr and 24.00 hr as compared to control animals. The similar changes were also recorded during the blockade of NO under conditions of hyperfunction indicating the important role of NO and melatonin in these processes. The rhythm acquired sinusoidal character. The average daily level was lower than the benchmark. The amplitude of the rhythm was significantly higher than that of animals that were under the standard light regime and amounted to the 26,3%. Thus in this case the correction by melatonin reduced the effect of blockade of synthesis NO.

Within the daily period the rhythm adjustment of the concentration index of endogenous creatinine was recorded with a violation of its phase structure (table I). The average daily level was 19,3 units and was lower than in the control and animals with hypofunction of the PG with blockade of synthesis NO. The combined effect of inhibiting NO synthesis and melatonin correction resulted in a decrease in the concentration index of endogenous creatinine.

Since the average daily excretion of potassium ions was probably lower than 12% of animals that were under physiological conditions it can be assumed that the synthesis of melatonin is one of the reasons for the disturbance of potassium homeostasis (table I) mechanisms (fig. 3).

Under such experimental conditions chronorhythmic rearrangements of the excretory renal function were accompanied by a decrease in urinary protein excretion over the course of the day (table I). Compared to the control group of animals and rats that were under the hypofunction of the PG and the blockade of NO synthesis the level of performance remained low (fig. 4). Thus under the influence of melatonin against the background of the blockade of NO synthesis, chronorhythmic alterations of architectonics and phase structure of the rhythms of most indicators of excretory renal function were observed. The decrease of the amplitudes of the chronorhythms was found which in our opinion is an important diagnostic feature of the stress of adaptive possibilities at the border of adaptation transition to unadaptation.

Conclusions

Based on the data of the conducted research series it was established that the effect of melatonin on the background of blockade NO synthesis leads to a decrease in the average daily urinary rhythm level relative to the control group of animals in the antiphasic structure relative to other groups of observation and also leads to a significant decrease in excretion of potassium ions in the urine during the observation period relative to control animals and rats with hypofunction PG under conditions of blockade synthesis NO.

The significant inhibition of glomerular filtration velocity was observed in control animals and rats with hypofunction of L-NNA which reduced the basal level of protein excretion in urine with displacement of the position of the acro- and battiphase rhythm, in control animals and rats with hypofunction of PG which blocked the synthesis NO which is a consequence of the combined effect of blockade NO synthesis and the effect of melatonin.

It should be noted that the administration of melatonin against the backdrop of blockade NO synthesis led to more pronounced changes in the integral characteristics of the indicators of renal function rather than with hypo and hyperfunction of this gland under blockade of synthesis NO. These facts indicate a complex mechanism for controlling the regulation of water-salt and acid-alkaline equilibrium in rats and convinces in the prominent integrative role of the brain’s epiphysis as well as the no less important role of the epiphyseal hormone melatonin in these processes.

References

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2. Agadzhanyan N.A., Brunin D.V., Radysh I.V., Ermakova N.V. Chronophysiological features of Central hemodynamic in women of reproductive age. Technol Liv Sys. 2014; 11, (1): 3-6.

3. Dzherieva I.S., Volkova N.I.. Rappaport S. I. Melatonin as a regulator of metabolism. Klin med. 2012; 90 (10): 27-30.

4. Jom L.O., Jonsson A. Hour does light affect melatonin. Мed Hypothes. 2008; 71 (3): 457-458.

5. Krestinina O.V., Odinokova S.V. Baburina Y.I., Azarashvili T.S. Krestinina O.V. Age-related effect of melatonin on permeability transition pore opening in rat brain. Biochem Sup Ser A Memb Cell Biol. 2013; 3 (4): 286-293.

6. Natochin Y.V. Fluid and electrolyte homeostasis – role of reflexes, hormones, incretins and autacoids is characterized. Fiziol Zh. 2011; 57 (5): 13-15.

7. Daniya K., Verma M., Dhankhan R. et al. Alteration of is chemia modified albumin and nitric oxide levels in hypothyroidish. Clin. Lab. 2014; 60 (6): 969-972.

8. Semenenko S., Tymofiychuk I., Boreyko L. et al. Peguliairities of melatonin effect on chronorhytmic organization of kidney acid-regulating function influenced by nitrogen monoxide synthesis blockade under conditions of pineal gland hypofunction. Georgian medical news. 2017; 10 (271): 117-122.

9. Dallmann R., Viola A.U., Tnokh L. et al. The human circadian metabolom. Proc Nat Acad Sci USR. 2012; 109 (7): 2625-2629.

10. Ilyaskin A.V., Baturin G.S., Katkova L.E. et al. Effect of hypoosmotic shock on the volume of renal collecting duct epithelial cells of brattleboro rats with hereditarily defective vasopressin synthesis. Doklady RAN. 2013; 453 (1): 102-105.

Authors’ contributions:

According to the order of the Authorship.

 

Conflict of interest:

The Authors declare no conflict of interest.

CORRESPONDING AUTHOR

Svitlana Semenenko

tel: +38050 5277151

e-mail: semenenko.svitlana@bsmu.edu.ua

Received: 12.06.2018

Accepted: 23.09.2018

Fig. 1. Daily mean levels of diuresis (мl/2 hours) in rats exposed to the blockade of NO synthesis and melatonin injection under conditions of pineal gland normal function

Fig. 2. Daily mean levels of glomerular filtration rate (mcl/min) in rats exposed to the blockade of NO synthesis and melatonin injection under conditions of pineal gland normal function

Fig. 3. Daily mean levels of concentration of potassium ions into urine (ммоl/l) in rats exposed to the blockade of NO synthesis and melatonin injection under conditions of pineal gland normal function

Fig. 4. Daily mean of the protein excretion (мg/2 hours) in rats exposed to the blockade of NO synthesis and melatonin injection under conditions of pineal gland normal function

Table I. Influence of nitrogen monoxide synthesis blockade and melatonin injection under the normal conditions of pineal gland on mesor (daily mean) and amplitude of the rhythms of the kidney excretion functions in albino rats ()

Parameters

Control animals

(n=36)

Blockade of nitrogen monoxide synthesis and melatonin injection under the normal conditions of pineal gland (n=36)

Mesor (daily mean)

Amplitude

(%)

Mesor (daily mean)

Amplitude

(%)

Diuresis, мl/2 hours

3,2±0,28

18,7±1,55

2,1± 0,22

p<0,01

22,1±1,31

Concentration of potassium ions into blood plasma, ммоl/l

5,1±0,29

24,8±1,41

4,9±0,11

4,2±0,31 р<0,001

Concentration of potassium ions into urine, ммоl/l

15,9±0,62

35,4±1,31

11,5±0,51 р<0,001

12,6±0,91 р<0,001

Excretion of potassium ions, мcмоl/2 hours

201,2±2,72

49,9±2,35

23,7±1,71 р<0,001

26,8±1,01 р<0,001

Concentration of creatinine into blood plasma, мcмоl/l

49,8±2,88

19,9±2,11

45,9±2,35

26,3±1,72 р<0,05

Excretion of creatinine, мcмоl/2 hours

3,5±0,06

16,9±1,91

1,6±0,18 р<0,001

27,2±2,22 р<0,01

Glomerular filtration rate, mcl/min

623,5±14,91

22,0±1,52

324,8±10,22 р<0,001

23,2±2,11 р<0,001

Relative water reabsorption, %

95,1±0,03

1,6±0,41

94,3±0,55

1,2±0,07

Endogenous creatinine concentration index, un

24,6±1,81

40,7±1,01

19,3±0,87 р<0,01

23,7±1,83 р<0,001

Protein concentration into urine, g/l

0,1±0,01

30,1±1,91

0,1±0,01

16,4±0,01 р<0,001

Protein excretion, мg/2 hours

0,2±0,03

27,8±1,22

0,1±0,01 р<0,01

23,6±1,21 р<0,01

Protein excretion, мg/100 мcl GF

0,1±0,01

32,8±1,62

0,1±0,01

18,6±0,01 р<0,001

Notes:

р – reliable difference between the parameters of the experimental and control animals;

n – number of animals