Androgen manipulation and vasopressin binding in the rat brain and peripheral organs

1994 ◽  
Vol 130 (3) ◽  
pp. 291-296 ◽  
Author(s):  
Xin Gao ◽  
Paddy Phillips ◽  
Brian Oldfield ◽  
Deborah Trinder ◽  
John Risvanis ◽  
...  

Gao X, Phillips P, Oldfield B, Trinder D, Risvanis J, Stephenson J, Johnston C. Androgen manipulation and vasopressin binding in the rat brain and peripheral organs. Eur J Endocrinol 1994;130:291–6. ISSN 0804–4643 It is now widely recognized that there is a sexual dimorphism in the development of arginine vasopressin (AVP) immunoreactivity in certain parts of the brain, and that changes in brain AVP immunoreactivity change with manipulation of androgen status. The aim of this experiment was to determine specifically any AVP receptor changes in response to manipulation of androgen levels using a selective V1 antagonist radioligand. Following castration, plasma testosterone levels fell and AVP immunoreactivity was reduced in the lateral septum and bed nucleus of the stria terminalis. With testosterone supplementation in castrated animals, the immunoreactivity in these regions was restored to a higher degree than in sham-operated animals. Central and peripheral V1 AVP receptor binding (as determined using the selective AVP V1 antagonist radioligand [125I](d(CH2)5,sarcosine7)AVP was not changed in any of the brain regions studied or in liver or kidney membranes from the three groups. This study demonstrates that there is no change in brain AVP receptor binding despite changes in regional AVP immunoreactivity in the brain, and excludes any confounding interaction with changes in oxytocin receptors. P A Phillips, Department of Medicine, The University of Melbourne, Austin Hospital, Heidelberg, Victoria 3084, Australia

1979 ◽  
Vol 57 (s5) ◽  
pp. 111s-113s ◽  
Author(s):  
Claire Baxter ◽  
J. Horvath ◽  
G. Duggin ◽  
D. Tiller

1. Angiotensin II receptor binding was studied in specific regions of rat brain at different ages from birth to 14 weeks. 2. The number of specific angiotensin II receptors increased in all regions during the first 2 weeks of life and then decreased to adult levels. Peak numbers of receptors were up to 10 times the adult numbers. 3. The midbrain and thalamus-hypothalamus had maximum numbers of angiotensin II receptors at 2 weeks of age, whereas the rest of the brain regions had maximum numbers at 1 week. 4. Saralasin-infusion experiments suggested that circulating angiotensin-related peptides could reach brain angiotensin II receptors in 2 week old rats, but not in 6 week old rats. 5. It is postulated that the centrally mediated actions of circulating angiotensin II may be particularly important in the newborn.


Endocrinology ◽  
2007 ◽  
Vol 148 (10) ◽  
pp. 5095-5104 ◽  
Author(s):  
Simone L. Meddle ◽  
Valerie R. Bishop ◽  
Effimia Gkoumassi ◽  
Fred W. van Leeuwen ◽  
Alison J. Douglas

Oxytocin plays a pivotal role in rat parturition, acting within the brain to facilitate its own release in the supraoptic nucleus (SON) and paraventricular nucleus, and to stimulate maternal behavior. We investigated oxytocin receptor (OTR) expression and activation perinatally. Using a 35S-labeled riboprobe complementary to OTR mRNA, OTR expression was quantified in proestrus virgin, 21- and 22-day pregnant, parturient (90 min. from pup 1 birth), and postpartum (4–12 h from parturition) rats. Peak OTR mRNA expression was observed at parturition in the SON, brainstem regions, medial preoptic area (mPOA), bed nucleus of the stria terminalis (BnST), and olfactory bulbs, but there was no change in the paraventricular nucleus and lateral septum. OTR mRNA expression was increased on the day of expected parturition in the SON and brainstem, suggesting that oxytocin controls the pathway mediating input from uterine signals. Likewise, OTR mRNA expression was increased in the mPOA and BnST during labor/birth. In the olfactory bulbs and medial amygdala, parturition induced increased OTR mRNA expression compared with pre-parturition, reflecting their immediate response to new stimuli at birth. Postpartum OTR expression in all brain regions returned to levels observed in virgin rats. Parturition significantly increased the number of double-immunolabeled cells for Fos and OTR within the SON, brainstem, BnST, and mPOA regions compared with virgin rats. Thus, there are dynamic region-dependent changes in OTR-expressing cells at parturition. This altered OTR distribution pattern in the brain perinatally reflects the crucial role oxytocin plays in orchestrating both birth and maternal behavior.


1979 ◽  
Vol 57 (6) ◽  
pp. 595-599 ◽  
Author(s):  
P. D. Hrdina ◽  
K. Elson

The effect of tricyclic antidepressants, chlorpromazine, and some monoamine oxidase inhibitors on the accumulation of [14C]choline by crude synaptosomal (P2) fraction from different regions of rat brain (cortex, striatum, and hippocampus) was investigated. Analysis of choline uptake kinetics resulted in high- and low-affinity components with different Michaelis constants. All tricyclic antidepressants tested inhibited in a dose-dependent manner the high-affinity choline uptake in the three regions, amitriptyline being the most potent. The IC50 values correlated significantly with the relative potencies of imipramine congeners in binding to muscarinic receptors in the brain. Neither tranylcypromine nor pargyline in concentrations up to 0.1 mM had any effect on choline transport. Concentrations of tricyclic antidepressants effective in inhibiting the uptake of choline failed to influence significantly the activity of choline acetyltransferase in brain regions examined. The results suggest that the effect of imipramine congeners on high-affinity choline uptake may be reflected in the anticholinergic properties of these compounds.


1984 ◽  
Vol 218 (1) ◽  
pp. 131-138 ◽  
Author(s):  
S F Leong ◽  
J B Clark

The development of key enzyme activities concerned with glucose metabolism was studied in six regions of the rat brain in animals from just before birth (-2 days) through the neonatal and suckling period until adulthood (60 days old). The brain regions studied were the cerebellum, medulla oblongata and pons, hypothalamus, striatum, mid-brain and cortex. The enzymes whose developmental patterns were investigated were hexokinase (EC 2.7.1.1), aldolase (EC 4.1.2.13), lactate dehydrogenase (EC 1.1.1.27) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49). Hexokinase, aldolase and lactate dehydrogenase activities develop as a single cluster in all the regions studied, although the timing of this development varies from region to region. Glucose-6-phosphate dehydrogenase activity, however, declines relative to glycolytic enzyme activity as the brain matures. When the different brain regions are compared, it is clear that the medulla develops its glycolytic potential, as indicated by its potential enzyme activity, considerably earlier than the other regions (hypothalamus, striatum and mid-brain), with the cortex and cerebellar activities developing even later. This enzyme developmental sequence correlates well with the neurophylogenetic development of the brain and adds support to the hypothesis that the development of the potential for glycolysis in the brain is a necessary prerequisite for the development of neurological competence.


Sensors ◽  
2019 ◽  
Vol 20 (1) ◽  
pp. 59
Author(s):  
Noor Kamal Al-Qazzaz ◽  
Mohannad K. Sabir ◽  
Sawal Hamid Bin Mohd Ali ◽  
Siti Anom Ahmad ◽  
Karl Grammer

Identifying emotions has become essential for comprehending varied human behavior during our daily lives. The electroencephalogram (EEG) has been adopted for eliciting information in terms of waveform distribution over the scalp. The rationale behind this work is twofold. First, it aims to propose spectral, entropy and temporal biomarkers for emotion identification. Second, it aims to integrate the spectral, entropy and temporal biomarkers as a means of developing spectro-spatial ( S S ) , entropy-spatial ( E S ) and temporo-spatial ( T S ) emotional profiles over the brain regions. The EEGs of 40 healthy volunteer students from the University of Vienna were recorded while they viewed seven brief emotional video clips. Features using spectral analysis, entropy method and temporal feature were computed. Three stages of two-way analysis of variance (ANOVA) were undertaken so as to identify the emotional biomarkers and Pearson’s correlations were employed to determine the optimal explanatory profiles for emotional detection. The results evidence that the combination of applied spectral, entropy and temporal sets of features may provide and convey reliable biomarkers for identifying S S , E S and T S profiles relating to different emotional states over the brain areas. EEG biomarkers and profiles enable more comprehensive insights into various human behavior effects as an intervention on the brain.


1994 ◽  
Vol 300 (2) ◽  
pp. 577-582 ◽  
Author(s):  
P T Kilpeläinen ◽  
O A Hietala

The activity of ornithine decarboxylase (ODC) measured in different regions of rat brain was highest in the hippocampus and lowest in the cerebellum. The ODC activity of a crude extract of the cerebellum was increased by the addition of GTP to the enzyme assay. Following dissociation of the ODC-antizyme complex by Sephadex G-75 chromatography in buffer containing 0.25 M NaCl, the GTP-activatable ODC was found in every brain region analysed. This GTP-activatable brain ODC has greater affinity for antizyme than the non-GTP-activatable brain ODC or the kidney ODC. The irreversible inhibitor of ODC, alpha-difluoromethylornithine (DFMO), inhibited approx. 60% of the ODC activity of all brain regions, whereas kidney ODC was inhibited totally by DFMO. When extracts of brain and kidney were incubated at 55 degrees C, kidney ODC was rapidly inactivated, but brain ODC was more heat-stable. Brain ODC, but not kidney ODC, was activated by GTP and ATP, and also by their deoxy forms. The K1/2 for activation of the enzyme was 2 microM for GTP and 40 microM for ATP. Using partially purified brain ODC, the activation by GTP was irreversible. These results demonstrate for the first time that the GTP-activatable ODC exists in the brain and is associated with the antizyme. The possible mechanisms of activation by GTP, the significance of this finding for the regulation of brain ODC, and the similarities to and differences from the GTP-activatable ODC found in certain rodent and human tumours are all discussed.


2004 ◽  
Vol 32 (05) ◽  
pp. 795-806 ◽  
Author(s):  
Hye-Jung Lee ◽  
Bombi Lee ◽  
Sun-Hye Choi ◽  
Dae-Hyun Hahm ◽  
Mi-Rye Kim ◽  
...  

We have previously shown that electroacupuncture (EA) at Shaohai and Neiguan ( HT 3- PC 6) points significantly attenuated stress-induced peripheral responses, including increases in blood pressure, heart rate and plasma catecholamines. In this study, we examined the central effect of EA on the expression of c-fos, one of the immediate-early genes in the brain of rats subjected to immobilization stress. Immobilization stress (180 minutes) preferentially produced a significant increase in Fos-like immunoreactivity (FLI) in stress-relevant regions including the paraventricular hypothalamic nucleus (PVN), arcuate nucleus (ARN), supraoptic nucleus (SON), suprachiasmatic nucleus (SCN), medial amygdaloid nucleus (AMe), bed nucleus of the stria terminalis (BST), hippocampus, lateral septum (LS), nucleus accumbens, and the locus coeruleus (LC). EA (3 Hz, 0.2 ms rectangular pulses, 20 mA) at HT 3- PC 6 on the heart and pericardium channels for 30 minutes during stress, significantly attenuated stress-induced FLI in the parvocellular PVN, SON, SCN, AMe, LS and the LC. However, EA stimulations at HT 3- PC 6 had no effect on FLI in the magnocelluar PVN, ARN, BST or the hippocampus. EA stimulation at HT 3- PC 6 had a greater inhibitory effect on stress-induced FLI than that at TE 5- LI 11, the triple energizer and large intestine meridian, or non-acupoints. These results demonstrated that EA attenuated stress-induced c-fos expression in brain areas. These results suggest that decreased c-fos expression in hypothalamic and LC neurons, among stress-related areas, may reflect the integrative action of acupuncture in stress response.


1992 ◽  
Vol 12 (4) ◽  
pp. 603-612 ◽  
Author(s):  
Anna M. Planas ◽  
Christian Prenant ◽  
Bernard M. Mazoyer ◽  
Dominique Comar ◽  
Luigi Di Giamberardino

The specific activity (SA) of free methionine was measured in plasma and in different regions of the rat brain at 15, 30, or 60 min after intravenous infusion of l-[14C- methyl]methionine. Within these time periods, an apparent steady state of labeled free methionine in plasma and in brain was reached. However, the brain-to-plasma free methionine SA ratio was found to be ∼0.5, showing that an isotopic equilibrium between brain and plasma was not attained. This suggests the presence of an endogenous source of brain free methionine (likely originating from protein breakdown), in addition to the plasma source. The contribution of this endogenous source to the content of free methionine varies significantly among the different brain regions. Our results indicate that the regional rates of protein synthesis measured with l-[11C- methyl]methionine using positron emission tomography would be underestimated, since the local fraction of brain methionine derived from protein degradation would not be considered.


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