scholarly journals The influence of cholinergic drugs on electroencephalogram of the gonadectomized female rabbits

2020 ◽  
Vol 18 (1) ◽  
pp. 23-28
Author(s):  
Natalia N. Kuznetsova
Keyword(s):  
Ache Inhibitor ◽  
Simultaneous Administration ◽  
Cholinergic Mechanisms ◽  
Cholinergic Drugs ◽  
Eeg Spectrum ◽  
General Power ◽  
The Brain

The results of investigation has shown, that after the gonadectomy of the rabbits-females the general power of EEG spectrum (GPS of EEG) changed under influence of cholinergic drugs. The sterilizathion of the animals leads to disorders of interaction between M- and N-cholinergic mechanisms in the brain. In particular, blockade of M-cholinoreceptors by metamizyl in intact and ovariectomized rabbits increased the GPS of EEG. The simultaneous administration of metamizyl with galantamine to intact females led to even greater increase of GPS of EEG, whereas the sterilized rabbits demonstrated its reduction. On the contrary, the application of the N-cholinoreceptors inhibitor gangleron with inhibitor of acetylcholinesterase (AChE) galantamine reduced the GPS of EEG in intact animals and increased it in gonadectomized rabbits in comparison with gangleron alone. Thus, the effect of M,N-cholinoblockators in combination with AChE inhibitor in sterilized rabbits changed the EEG spectrum to opposite in comparison with intact females.

N-(3,5-dinitrophenyl)-5-methoxytryptamine, a novel melatonin antagonist: effects on sexual maturation of the male and female rat and on oestrous cycles of the female rat

1988 ◽  
Vol 116 (1) ◽  
pp. 43-53 ◽  
Author(s):  
M. Laudon ◽  
Z. Yaron ◽  
N. Zisapel
Keyword(s):  
Drinking Water ◽  
Adult Female ◽  
Sexual Maturation ◽  
Young Male ◽  
Female Rats ◽  
Male Rats ◽  
Female Rat ◽  
Simultaneous Administration ◽  
Serum Concentrations ◽  
The Brain

ABSTRACT N-(3,5-dinitrophenyl)-5-methoxytryptamine (ML-23) has recently been synthesized and shown to antagonize the inhibitory effect of melatonin on the release of dopamine in vitro from the hypothalamus of female rats. In the present study the ability of ML-23 to inhibit in vivo the following melatonin-mediated effects was investigated: (1) delayed sexual maturation of young male rats, (2) delayed sexual maturation of young female rats, (3) inhibition of ovulation in mature female rats and (4) re-establishment of oestrous cycles in adult female rats maintained in continuous light. The inhibitory effect of daily melatonin injections, given in the afternoon, on the growth of the prostate gland and seminal vesicles and on serum testosterone concentrations in young male rats was prevented by daily injections of ML-23. Daily injections of ML-23 alone did not affect sexual maturation of young rats. In young male rats treated through the drinking water with melatonin, the growth of the accessory sex organs, but not that of the testes, was delayed and serum concentrations of testosterone were lower than in untreated rats. Administration of ML-23 through the drinking water increased serum concentrations of testosterone but did not significantly affect the weights of the accessory sex organs. Simultaneous administration of ML-23 and melatonin through the drinking water prevented completely, in a dose-dependent manner, the melatonin-mediated decrease in epididymal weights and in serum concentrations of testosterone and partially inhibited the delayed growth of the prostate glands and seminal vesicles. In young female rats treated with melatonin through the drinking water for 30 days, the growth of the ovaries was inhibited and serum concentrations of oestradiol were lower than in untreated rats. The growth of the uterus was not significantly affected. Administration of ML-23 through the drinking water did not significantly affect uterine and ovarian weights or oestradiol concentrations. Simultaneous administration of melatonin and ML-23 through the drinking water prevented completely the melatonin-mediated decrease in ovarian weights and in serum oestradiol concentrations. Ovulation during presumptive oestrus was prevented in adult female rats treated through the drinking water for 7 days with melatonin. Administration of ML-23 alone did not significantly affect the average numbers of ova shed and corpora lutea present. Simultaneous administration of ML-23 and melatonin prevented completely the melatonin-mediated inhibition of ovulation; the average number of ova shed was the same as in controls. Suppression of reproductive cycles occurred in adult female rats after long-term exposure to continuous light. This suppression was prevented by daily injections of melatonin in the afternoon; the incidence of constant oestrus decreased by 80%. Simultaneous injection of ML-23 and melatonin into rats maintained under continuous illumination prevented the effect of melatonin, and all the animals remained in constant oestrus. Administration of ML-23 alone did not alter the incidence of constant oestrus. A tritium-labelled derivative of ML-23 was prepared and administered orally to male rats. Peak concentrations of ML-23 occurred in the blood within 30 min after feeding and disappeared subsequently with a half-life of about 42 min. Intraperitoneal injection of [3H]ML-23 resulted in the appearance of peak concentrations of the drug in the brain within 20 min. The effects of ML-23 on serotonin S1 and S2 receptors, dopamine D2 receptors and melatonin receptors in the brain of the male rat were investigated using [3H]serotonin, [3H]spiperone and 2-[125I]iodomelatonin respectively. The binding of [3H]serotonin to brain synaptosomes and of [3H]spiperone to synaptosomes prepared from the cortical and caudate regions of the cerebrum was unaffected by ML-23 (10 μmol/l), whereas the binding of 2-[125I]iodomelatonin to brain synaptosomes was entirely inhibited. The results demonstrate the potency of ML-23 in antagonizing melatonin-mediated effects in the male and female rat in vivo. The drug may be administered to the animals simply through the drinking water, for relatively long periods without apparent deleterious effects on survival and welfare. ML-23 is accessible to both central and peripheral sites and acts specifically on melatonin but not on serotonin or dopamine receptors in the brain. The availability of a melatonin antagonist offers new opportunities for exploring the physiological role of melatonin in the neuroendocrine system. J. Endocr. (1988) 116, 43–53

CSF acidosis augments ventilation through cholinergic mechanisms

1989 ◽  
Vol 66 (6) ◽  
pp. 2565-2572 ◽  
Author(s):  
M. D. Burton ◽  
D. C. Johnson ◽  
H. Kazemi
Keyword(s):  
Minute Ventilation ◽  
Neuronal Firing ◽  
Base Line ◽  
Dependent Manner ◽  
Acidic Ph ◽  
Cholinergic Mechanisms ◽  
Concentration Dependent Manner ◽  
Positive Effects ◽  
Ventilatory Effects ◽  
The Brain

Ventilation is influenced by the acid-base status of the brain extracellular fluids (ECF). CO2 may affect ventilation independent of changes in H+. Whether the acidic condition directly alters neuronal firing or indirectly alters neuronal firing through changes in endogenous neurotransmitters remains unclear. In this work, ventriculocisternal perfusion (VCP) was used in anesthetized (pentobarbital sodium, 30 mg/kg) spontaneously breathing dogs to study the ventilatory effects of acetylcholine (ACh), eucapnic acidic (pH approximately 7.0) cerebrospinal fluid (CSF), and hypercapnic acidic (pH approximately 7.1) CSF in the absence and presence of atropine (ATR). Each animal served as its own control. Base line was defined during VCP with control mock CSF (pH approximately 7.4). With ATR (4.8 mM) there was an insignificant downward trend in minute ventilation (VE). ACh (6.6 mM) increased VE 53% (n = 12, P less than 0.01), eucapnic acidic CSF increased VE 41% (n = 12, P less than 0.01), and hypercapnic acidic CSF increased VE 47% (n = 6, P less than 0.01). These positive effects on ventilation were not seen in the presence of ATR. This suggests that acidic brain ECF activates ventilatory neurons through muscarinic cholinergic mechanisms. Higher concentrations of ACh increased ventilation in a concentration-dependent manner. Higher concentrations of ATR decreased ventilation progressively, resulting in apnea. The results suggest that ACh plays a significant role in the central augmentation of ventilation when the brain ECF is made acidic by either increasing CSF PCO2 or decreasing CSF bicarbonate.

Autonomic and cholinergic mechanisms mediating cardiovascular and temperature effects of donepezil in conscious mice

2021 ◽  
Author(s):  
Aaron J Polichnowski ◽  
Geoffrey A Williamson ◽  
Tesha Elise Blair ◽  
Donald B Hoover
Keyword(s):  
Methyl Bromide ◽  
Therapeutic Potential ◽  
Inflammatory Diseases ◽  
Pressor Response ◽  
Atropine Sulfate ◽  
Ache Inhibitor ◽  
Cholinergic Mechanisms ◽  
Cholinergic Pathways ◽  
Autonomic Pathways ◽  
Drug Treatments

Donepezil is a centrally-acting acetylcholinesterase (AChE) inhibitor with therapeutic potential in inflammatory diseases; however, the underlying autonomic and cholinergic mechanisms remain unclear. Here, we assessed effects of donepezil on mean arterial pressure (MAP), heart rate (HR), HR variability, and body temperature in conscious adult male C57BL/6 mice to investigate the autonomic pathways involved. Central vs. peripheral cholinergic effects of donepezil were assessed using pharmacological approaches including comparison with the peripherally-acting AChE inhibitor, neostigmine. Drug treatments included donepezil (2.5 or 5 mg/kg s.c.), neostigmine methyl sulfate (80 or 240 μg/kg i.p.), atropine sulfate (5 mg/kg i.p.), atropine methyl bromide (5 mg/kg i.p.), or saline. Donepezil, at 2.5 and 5 mg/kg, decreased HR by 36±4 and 44±3% compared to saline (n=10, P<0.001). Donepezil, at 2.5 and 5 mg/kg, decreased temperature by 13±2 and 22±2% compared to saline (n=6, P<0.001). Modest (P<0.001) increases in MAP were observed with donepezil after peak bradycardia occurred. Atropine sulfate and atropine methyl bromide blocked bradycardic responses to donepezil, but only atropine sulfate attenuated hypothermia. The pressor response to donepezil was similar in mice co-administered atropine sulfate; however, co-administration of atropine methyl bromide potentiated the increase in MAP. Neostigmine did not alter HR or temperature but did result in early increases in MAP. Despite the marked bradycardia, donepezil did not increase normalized high frequency HR variability. We conclude that donepezil causes marked bradycardia and hypothermia in conscious mice via activation of muscarinic receptors while concurrently increasing MAP via autonomic and cholinergic pathways that remain to be elucidated.

scholarly journals Chronic Cerebral Ischaemia Forms New Cholinergic Mechanisms of Learning and Memory

2010 ◽  
Vol 2010 ◽  
pp. 1-17 ◽  
Author(s):  
E. I. Zakharova ◽  
Z. I. Storozheva ◽  
A. M. Dudchenko ◽  
A. A. Kubatiev
Keyword(s):  
Comparative Analysis ◽  
Learning And Memory ◽  
Water Maze ◽  
Brain Structures ◽  
Molecular Profile ◽  
Brain Pathology ◽  
Synaptic Organization ◽  
Cholinergic Mechanisms ◽  
The Individual ◽  
The Brain

The purpose of this research was a comparative analysis of cholinergic synaptic organization following learning and memory in normal and chronic cerebral ischaemic rats in the Morris water maze model. Choline acetyltransferase and protein content were determined in subpopulations of presynapses of “light” and “heavy” synaptosomal fractions of the cortex and the hippocampus, and the cholinergic projective and intrinsic systems of the brain structures were taken into consideration. We found a strong involvement of cholinergic systems, both projective and intrinsic, in all forms of cognition. Each form of cognition had an individual cholinergic molecular profile and the cholinergic synaptic compositions in the ischaemic rat brains differed significantly from normal ones. Our data demonstrated that under ischaemic conditions, instead of damaged connections new key synaptic relationships, which were stable against pathological influences and able to restore damaged cognitive functions, arose. The plasticity of neurochemical links in the individual organization of certain types of cognition gave a new input into brain pathology and can be used in the future for alternative corrections of vascular and other degenerative dementias.

The Effects of Physostigmine during the Acquisition of Avoidance Behaviour as a Function of the Intersession Interval

1974 ◽  
Vol 26 (3) ◽  
pp. 387-394 ◽  
Author(s):  
Tom Cox
Keyword(s):  
Learning And Memory ◽  
Cholinesterase Inhibitors ◽  
Avoidance Behaviour ◽  
Avoidance Task ◽  
Cholinergic Mechanisms ◽  
Escape Behaviour ◽  
Biochemical Basis ◽  
Shuttle Box ◽  
Intersession Interval ◽  
The Brain

Rats were trained and tested on an avoidance task in a shuttle box. The change in the performance of the control rats over two sessions was found to be a U-shaped function of the interval between the sessions. The change in performance of rats injected with physostigmine prior to the second session was also found to be a U-shaped function of the intersession interval, although the drug was shown to impair avoidance behaviour. These results are consistent with those of Hamburg (1967) and of Biederman (1970), and support the general contention that cholinergic mechanisms in the brain are involved in the control of avoidance and escape behaviour in the rat. They do not, however, necessarily support the hypothesis advanced by Deutsch (1969, 1971) to describe a biochemical basis of learning and memory, especially if it is used to explain the effects of cholinesterase inhibitors on avoidance behaviour in the shuttlebox.

scholarly journals EEG power spectral density in locked-in and completely locked-in state patients: a longitudinal study

2020 ◽  
Author(s):  
Arianna Secco ◽  
Alessandro Tonin ◽  
Aygul Rana ◽  
Andres Jaramillo-Gonzalez ◽  
Majid Khalili-Ardali ◽  
...  
Keyword(s):  
Spectral Density ◽  
Power Spectral Density ◽  
Resting State ◽  
Relevant Information ◽  
Eeg Spectrum ◽  
Power Spectral ◽  
Significant Difference ◽  
Communication Ability ◽  
The Brain ◽  
Lateral Sclerosis

Abstract Persons with their eye closed and without any means of communication is said to be in a completely locked-in state (CLIS) while when they could still open their eyes actively or passively and have some means of communication are said to be in locked-in state (LIS). Two patients in CLIS without any means of communication, and one patient in the transition from LIS to CLIS with means of communication, who have Amyotrophic Lateral Sclerosis were followed at a regular interval for more than 1 year. During each visit, resting-state EEG was recorded before the brain–computer interface (BCI) based communication sessions. The resting-state EEG of the patients was analyzed to elucidate the evolution of their EEG spectrum over time with the disease’s progression to provide future BCI-research with the relevant information to classify changes in EEG evolution. Comparison of power spectral density (PSD) of these patients revealed a significant difference in the PSD’s of patients in CLIS without any means of communication and the patient in the transition from LIS to CLIS with means of communication. The EEG of patients without any means of communication is devoid of alpha, beta, and higher frequencies than the patient in transition who still had means of communication. The results show that the change in the EEG frequency spectrum may serve as an indicator of the communication ability of such patients.

scholarly journals Augmented central cholinergic mechanisms in spontaneously hypertensive rats. Involvement of deranged noradrenergic mechanisms in the brain.

1984 ◽  
Vol 25 (3) ◽  
pp. 397-410 ◽  
Author(s):  
Hakuo TAKAHASHI ◽  
Atsushi INOUE ◽  
Kazuo TAKEDA ◽  
Hiroshi Okajima ◽  
Susumu SASAKI ◽  
...  
Keyword(s):  
Spontaneously Hypertensive Rats ◽  
Hypertensive Rats ◽  
Cholinergic Mechanisms ◽  
Spontaneously Hypertensive ◽  
The Brain
Sign in / Sign up

Export Citation Format

Share Document